How to Fix Chatter or a Really Poor Finish on the Valve

April 10th, 2019

Valve Finish

The following will resolve a valve finish issue and is also a good part of the process of setting up a new Kwik-Way SVS II Deluxe Valve Refacer. 

Chatter or a Poor Finish

on an engine valve after grinding is almost always the result of vibration somewhere.  There are other things that can cause it too, but the most common is vibration. There are little adjustments that can be made to try and clean things up.  Slow the valve spin, dress the stone more aggressively or less aggressively.  Maybe even try a different grinding wheel. Those can all affect the finish of a valve.  But if it's a really bad finish, chances are you have a vibration somewhere.

Fixing the Chatter Causing Vibration

The Kwik-Way Model SVSII Deluxe machine is a High-Performance machine. The cast iron base and special treatments to parts and sections of the machine make it the most accurate and long lasting machine of it's kind. But even so, when it gets out of calibration it will happily produce a bad finish. To prevent this the technician must be diligent with maintenance and cleaning. Afterall you are producing fine particles of metal and stone from two spinning objects.  Even though you are using a liquid to help capture this debris it's still getting around.

Start with the Big Motor

Start by making sure your machine is turned off and unplugged. While standing in front of the Valve Refacer, move the traverse arm to a vertical position. Then place both hands on the two aluminum end caps of the main motor housing. Now attempt to move the housing away from you and towards you. Does it move?  If it does you likely have found the reason for your bad valve finish. 

Adjusting the Gibs

Leave the traverse lever in the verticle position. Go around behind the machine and locate the three Allen head screws just under the black housing cover.  Start with the screw that is near the large grinding stone. Tighten until the traverse lever won't move anymore.  Now slowly back off the screw while trying to move the handle until you are able to move the handle its full range with a noticeable amount of smooth drag.  Put the traverse lever vertical again and repeat the same process on the screw on the other end. 

Now move back to the front of the machine and check to see that the rocking movement you felt earlier is now gone.  If not you'll need to repeat the process above or you may have a warn or damaged gib. But if the movement is gone you can finish by repeating the same steps we did to the outer two screws on the middle screw. While this will likely have solved your bad valve finish problem I would recommend you check all the other possible adjustments I'm going to give you.

Switch Sides

Over on the Chuck side of the machine, there are several different areas that need to be looked at to ensure everything is correct. Let's start with the easy things to check.  The belt that drives the chuck is a ribbed belt for a reason.  This belt needs to be as loose as possible without slipping.  This is to prevent any motor vibration from transferring to the back end of the chuck.  Vibration back here would be amplified at the other end of the chuck where your valve is grinding.

Next, you need to check the chuck for lateral movement.  Grab the valve end and the other end of the chuck and see if you can move it side to side or front to back would be a better way of saying it.  There should be no movement from front to back.  If you have movement then you need to loosen the set screw on the spline pully on the back of the chuck and while pushing the valve end of the chuck toward the back slide the spline pully up until it just touches the side of the rear saddle mount of the chuck.  Then tighten the setscrew back up.

Chuck Gibs 

Similar to how the grinding motor side had gibs to be adjusted the chuck also has a set of gibs that can become out of adjustment.  To check this you first lock your chuck degree adjustment and then try and move the valve feed hand wheel side to side while looking were the cast plate the chuck is mounted to meets the other cast plate that has the degree markings.  IF you see a very small bead of oil moving where those two plates meet then you probably need to adjust your chuck gibs. 

These are adjusted one at a time until they are tight then back them off slightly.  When you think you have it, do the test again to be sure.

Adjusting the Chuck Saddles

The last item to investigate is the chuck saddles. These have the capped oilers on them and should be oiled on a regular basis.  Over time the chuck shaft and these saddles will become worn and need to be adjusted.  Remove the chuck belt to make these adjustments.  Start with the saddle closest to the chuck.  While turning the chuck with one hand tighten the saddle bolt until you feel resistance and back off ever so slightly until no resistance is felt.  Move to the rear of the chuck and do the same.  Finish by repeating the first operation.

After All These Adjustments

If you still have a finish problem it could be a dirty or worn out Chuck.  Do a full disassembly of your Chuck and clean it with denatured alcohol then reassemble using ATF as a lubricant. Which, by the way, is the only thing you should ever use to lubricate your Chuck ball area. Instructions to disassemble your Chuck can be found in the manual and a current manual is available on the Kwik-Way website as a free download.  

After cleaning, check the runout of your Chuck.  Use a known straight shaft like the pilot for seat grinding and place it in the chuck.  Set a dial indicator about 1 inch from the face of the Chuck and check your runout. Excessive runout at this point would indicate the need to replace the Chuck. 

If your runout is good, then it might be your stone and/or the way you are dressing your stone.  The stone should match the type of metal you are grinding and the machine manual will tell you the proper way to dress the stone for the type of cut you are attempting.

Still having a problem even after doing all the steps above?  Then you should call Irontite Tech Services for more help.  But in most cases, the above guide will solve your poor valve finish issues.



Boring Bar will not Repeat on Bore Size

July 1st, 2016

A very common concern with any boring bar is that the bar sometimes will not repeat on bored size. This can be caused by one a few different things, or a combination of more than one.

You set your mike and bore a hole and find the hole is oversized, you reset the mike and the next hole is then undersized, obviously there is something that is not right.

First thing we would look for are scores or scratches in the micometer face. If the mike is damaged, the bar will not repeat.The mike should be returned to KW and the face reground and repaired.

Micrometer stem bend, will cause the same problems depending on the amount of bend and the amount of stock to be removed. A quick way to determine if the stem is bent is to insert a feeler gauge (.002) between the face of the mike and the tool bit, then tighten the bit. The feeler gauge should stay in place, and if you slowy rotate the mike in the boring head, the tension in the feeler gauge should not increse or decrease. If it does, the stem is bent and requires replacement.

Another thing to check is if the micrometer not locating into the boring head correctly. The stem of the mike has a V-groove in it which works with a spring loaded ball bearing to insure correct position of the mike into the head every time. If the groove is worn or the ball is out of adjustment, the bar will not repeat on size. The micrometer should "snap" into the head and when slight rearward pressure is applied, the mike should snap back into the boring head. If it does not the ball positon will need to be adjusted. Contact Tech Services for assistance in this case.

If you tighten the tool bit and the tool bit moves away from the feeler gauge, and the feeler becomes loose, there is a different problem. Either the tool gib, tool holder or boring head is worn. You can examine the tool holder quite easily by simply checking the angle where the gib plate contacts the tool holder for visable wear and also feel it for any step. If worn, it will require replacement. You will need to remove the gib from the boring head to examine it for wear also, if the tool holder is worn, it is likely the gib will be worn also.

Boring Bar will not Repeat on Bore Size

The boring head can also be worn, and cause the same problem as the tool gib or holder. If the boring head is worn, then the head will need to be replaced. Rebuilding a boring head is only something that the factory can do, and all heads may not be repairable. A combination of two or more of these concerns may be found on the same machine. These findings are normally on very old or high service units.

These are but a few possible causes for potential boring errors in bore size.

As always please contact KW Tech services for further help if required.


Micrometer Calibration for all Kwik-Way Model Boring Bars

February 1st, 2012

From time to time it may become necessary to re-calibrate your boring bar micrometer. Kwik-Way can not calibrate  your micrometer here at our facility due to the fact that it must be calibrated to the boring bar that it is used in.

Please follow the the instructions carefully and your micrometer will be re-calibrated and accurate again within minutes.

Model FW-II Pictured Click Here for More Info

1. Using a scrap block, center the boring bar to the cylinder to be bored, and tighten the base clamp screw.

2. Raise the boring bar up to allow the tool holder and bit to be installed into the boring head.

3  With the tool holder and bit pushed back into the boring head as far as it will go, tighten the gib set screw. Now lower the boring head until the the tool bit is just into the top of the bore.

4.  Loosen the bib screw and allow the tool to carefully come out and contact the cylinerbore. Tighten the gib screw.

5.  Raise the boring head to allow the boring bar mike to be inserted into the boring head. NOTE: Have the micrometer adjusted large enough so that the tool bit will not contact the face on insertion.

6.  Slowly rotate the micrometer spindle untl the face of the mike JUST touches the tool bit. Now remove the micrometer and advance the reading by .010 to .015, then tighten the micrometer lock screw.

7.  Insert the micromenter back into the boring head and loosen the gib set screw to allow the tool bit to contact the face.(Use caution so as no to have the tool bit scratch the face of the micrometer) Tighten the gib set screw.

8.  Bore the cylinder.... now measure the actual finished size. DO NOT  loosen or remove the boring bar. Take the measurement with the bar in place.

9.  Place the stem of the boring bar micrometer into a vise with soft jaws so as not to damage the stem. Loosen the allen set screw found in the rear os the mike thimble in the knurled area.

10. Carefully rotate the thimble so that the mike now reads your bore size. Tighten the set screw.

11. Now loosen the micrometer lock screw and rotate the thimble either clockwise or counter clockwise, whichever direction is closer to thimble "0". Now re-tighten the micrometr lock screw at "0". If necessary, loosen the thimble set screw and slip the thimble up or down until the 0 is on the appropriate black line on the body of the micrometer then tighten the thimble set screw.

12. Loosen the micrometer lock screw and rotate the thimble to the reading of  the bore size in your test cylinder. Now add .010 to the reading and rebore the cylinder. Measure the cylinder to verify size, fine tune your micrometer reading if necessary.

Valve Chuck Disassembly / Assembly Instructions

January 31st, 2012

4mm Valve Chuck Disassembly / Assembly Tool

PN: 012-1054-60

[This tool is required to perform the following operations]

Disassembly Instructions

STEP 1: Remove the chuck cover from the Chuck Bearing Assembly, being careful not to pull any wires from the cover.. Rotate the Chuck so that the Grind Mark on the front collar and the Yellow Mark on the Spring are Vertical as show in the photo below.

STEP 2: Remove the (3) three 8 x 32 x 5/16 slot head screws from the Chuck End Cap (Black) shown below.

STEP 3: Use the Disassembly Tool (picture at the top of this document) which is standard equipment with your machine, put the 8 x 32 screws (3) into the chuck shaft in a 1/4 of an inch. Put the 1/4 x 20 Hex Head Bolt finger tight against the End Plate.

STEP 4: Remove the Chuck Yoke.

STEP 5: Loosen the 1/4 x 20 Hex head bolt counter clockwise. As you release the 1/4 x 20 bolt, the spring pressure should begin to release.. NOTE: You may need to soak the chuck in Automatic Transmission Fluid to remove grit and make the collars slide easier.

STEP 6: Remove the Chuck Disassembly Tool.

STEP 7: Begin to remove the outer collar from the chuck shaft. Next, remove the Loading Cup with the Four (4) springs. The large spring and inner collar will be removed along with the Thrust Step Washer. As you take the Inner collar off the steel chuck balls(9/16) may fall out of the chuck shaft.

STEP 8: Remove the Chuck Handwheel and belt from the chuck shaft. Remove the chuck from the chuck bearing assembly. Clean all parts with a parts cleaning solvent.

Assembly Instructions

STEP 9: (1) Put the shaft back in the chuck bearing slide, use transmission fluid only and coat the chuck shaft. Make sure the keys are vertical.

(2) Put the thrust washer, spring, and (3) three rear balls back on the chuck shaft, making sure that the Yellow mark is lined up with the Keys. hold on to the bottom balls so they don't fall out of the shaft.

(3) Slide on the Inner collar, so all three rear balls are inside of the collar.

(4) Put the front set of balls in the shaft. Install the loading cup with four(4) springs facing out.

(5) Install the outer collar, making sure the grind mark is lined up with the keyways.

(6) Reinstall the Disassembly tool. Put the three screws (8 x 32) in one quarter (1/4) of an inch. Begin to tighten the 1/4 x 20 bolt, making sure that the collars are still lined up with the keys. Run 1/4 x 20 bolt in until it is tight.

(7) Reinstall the Chuck Yoke.

(8) Remove the Disassembly Tool and reinstall the chuck End Cap with the three 8 x 32 screws.

(9) Reinstall the chuck Handwheel and Belt, making sure the chuck and chuck handwheel are snug to the chuck bearing slide.

(10) Reinstall the chuck cover. Make sure there are no wires touching the chuck.


April 20th, 2012
by Kwik-Way Products Inc.

For the past three or four decades the automotive industry witnessed substantial reductions in the number of valve servicing operations being performed. Leaded, high octane fuel burned in high compression engines developing high horsepower was the reason.

Even when these engines did need valve service the car owner might not be aware of it because his car's engine had a great excess of power which he hardly ever called upon.

Today the picture is changing. Lower compression ratios and unleaded fuels are the order of the day. They are the result of the need to reduce air pollution. And with these new conditions comes the need for maintaining high engine efficiency if performance and emission control standards are to be maintained

Valve misalignment can occur in a comparatively new engine of any make. How many car operators know or understand this? The service shop operator must begin to develop new means and methods for selling service, and especially for selling car owners on the importance of servicing valve and valve seats. He can easily do this by explaining the benefits that will be effected from a valve realigning operation.

Above is a new valve, true and mechanically accurate in all its proportions — the condition in which it is installed in an engine. The valve face and the valve stem are concentric with the same center line — the center line of the valve stem itself.

Above is a warped valve. The warp- age occurs only in that part which is subjected to extreme heat — the portion above the guide — and in the valve head. The valve face must be restored to concentricity with the portion of the stem that operates in the guide.


Years ago it was customary for engine manufacturers to stack engine blocks out in the weather so that they might become seasoned. These were corded up like wood. Tracks were laid between the piles and workmen were kept constantly busy bringing in the blocks and facing off first the top and then the bottom; then placing them out in the weather again for another period of seasoning between machine operations. All of this was done to eliminate casting strain. This seasoning operation as a rule took from six months to a year after the casting was made.

Compare this with our present day method of pouring iron ore into an electric furnace and having it come out of the plant in from forty-eight to sixty hours — a complete running engine. These blocks are normalized or heat-treated to eliminate casting strains. But remember! When these blocks are heated and cooled over a period of time in the operation of an engine, or when the head nuts or bolts are not drawn down evenly with a torque wrench, the different shapes and radii of the manifold near the valve guide will cause misalignment of the guide to the seat, and must be corrected in order to get maximum performance from the engine.


Since the introduction of hardened valve seats it is impossible for the valve to hammer in as before. Therefore, the misalignment caused by warping of or changing of the shape of the metal in the block will set up a friction between the valve stem and the valve guide. This will soon wear the valve guide as well as the valve stem and to a point that will partially destroy the effectiveness of the valves. A normally worn valve guide is illustrated above. It is worn at points A-B at top left hand and at bottom right hand for the reason that the valve seat is higher at the right hand side. The valve strikes the high side of the seat first, then bounces to the left. As the valve spring pulls the valve down, valve stem friction causes the wear as shown.


Another factor entering into valve misalignment is the distorting strain set up in the block or head due to the unevenness of tightening which results when a torque wrench is not used. Due to differences in stance of the operator, and other human factors, some of the head nuts or bolts are tightened excessively if torque is not measured. This always happens when a torque wrench is not used. In tightening head nuts or bolts, follow factory torque recommendations.

If you will check the valve seat nearest the bolts that are tightened excessively you will find the part of the seat nearest the bolt will be worn shiny; while the side of the seat opposite to or away from the bolt will be pitted or burned. It therefore follows that a properly aligned valve job may easily be spoiled by improper tightening of cylinder head nuts or bolts.

A properly aligned valve job may easily be spoiled by improper tightening of cylinder head nuts or bolts. The remedy is simple. It is as easy to use a torque wrench as any socket handle.


Several mei.iods are being used today to locate the grinder for realigning and resurfacing valve seats. There is, however, one accepted method that engineering practice has never improved upon. As an illustration, it has been common practice in machine shops for the past thirty or forty years to use what is known as a "machine arbor." This is a piece of hardened and ground steel microscopically tapered from end to end. Whenever a piece of precision work having a hole in the center was brought back to a lathe for machining, such an arbor was used to keep the machine work concentric with the hole in the center of the piece.

The Kwik-Way Manufacturing Company recognized the infallible accuracy of this procedure and designed a Tapered Arbor to be used for centering the valve seat alignment operation. The application of this arbor to the operation of servicing valve seats is covered by patents owned by the Kwik-Way Manufacturing Company and although widely imitated, it is not or should not be made available for this use by other manufacturers.


The Kwik-Way Tapered Arbor, commonly known as a Pilot, is microscopically tapered throughout the stem (the part that enters the guide). When inserted in the guide it takes its alignment from the least worn portion of the guide, which is towards the center, and not from the bell mouth portions on either end. Note (illustration at right) that the arbor does not contact the worn portions A-B at top and bottom of the guide and is not misaligned by those worn portions. It is accurately aligned by the unworn part. The Kwik-Way Eccentrimeter (below) measures the concentricity of the valve seat with relation to the guide. Some of the imitations have a straight surface for the greater portion of the stem with a conical or cork- shaped part for about an inch at the top. Since the valve has been crowded over to one side of the valve guide due to misalignment and the peculiarities of valve spring tension, the wear caused by this crowding of the valve stem to one side makes the top portion of the guide a most unsatisfactory point from which to locate for reconditioning of the seat. The seat cannot be reconditioned and realigned so it will be concentric with the actual center line of the valve guide.


In reconditioning a valve seat in an engine that has had considerable use, it is first necessary to determine whether or not the wear in the guide is beyond the point where the guide will be satisfactory for further use.

Through the use of the Kwik-Way Tapered Arbor the amount of wear can be determined. Kwik-Way Tapered Arbors are manufactured in steps of one-thousandth of an inch in undersize and oversize. By using a range of arbors, the amount of guide wear may easily be determined. The arbor, when inserted in the guide, actually becomes a plug gage for the worn guide. It is not good practice to use guides that are worn more than .003".

Insert another type arbor in a valve guide where there is considerable wear at the top and bottom. Try such an arbor as mentioned in preceding paragraphs and there will be an excessive misalignment due to the wedging of the cork or conical-shaped part of the arbor into the worn portion of the guide. Note (illustration left) that the conical or cork-shaped upper portion of that type arbor or pilot will contact the upper worn portion of the guide which also causes the lower portion to contact the bottom worn section of the guide. It is, therefore, misaligned by these worn portions. By checking such an arbor with an indicator, it is easy to prove this point as it is almost impossible to get the same reading twice. The Kwik-Way Tapered Arbor may be reinserted any number of times and checked with an indicator, and it will be proven that it will properly align itself each time it is inserted. It will be found that a seat trued up from a Kwik-Way Tapered Arbor is concentric with the actual center line of the valve stem guide.


The valves in an engine have numerous functions. First, they must permit the intake of fuel and air. Then they must seal compression. After the explosion the exhaust valve must permit the burned gases to leave the combustion chamber. Then there is one other function that valves must perform. They must streamline these gases and make it possible for them to move into and out of the combustion chamber as rapidly as possible, and, when the gases leave the combustion chamber, they must be so directed that they will not swirl or congest in a manner that will prevent the complete scavenging of the cylinder. The terrific pressure at which the gases pass through the exhaust manifold will normally create a vacuum in the cylinder, which in turn will assist in the complete scavenging of the cylinder.

Years ago, before engines operated at a high rate of speed, the matter of streamlining the gases was not considered an important one. When it is considered that at an average speed of fifty miles per hour there are twenty intakes, twenty explosions and twenty exhausts in each cylinder every second, it is not difficult to realize the importance of streamlining the gases. Automotive engineers today recognize this and in many instances have changed the shape of the valve towards the tulip design or designed them with a large fillet on the under side of the valve. The purpose of this fillet is to streamline the gases so they will pass freely out of the exhaust manifold. Most poppet valves are made at an angle of forty-five degrees, and being round they permit, (provided the valve is properly aligned), the exhaust gases to rush towards each other in a circle and under terrific pressure at an enormous velocity. This actually creates a vacuum that completely scavenges the cylinder. If the gases are not guided by the fillet under the valve, they collide and swirl, so to speak, which will cause a congestion in the manifold. This congestion will work against the proper elimination of the gases.


For this reason service mechanics should avoid cutting away the port below the valve seat and should be very particular not to destroy the radius that may be above the valve seat in diesel- type engines especially. This radius was placed there for a purpose by the designer of the engine.


Inasmuch as the shape of the valve and stem have the effect of streamlining the gases, a valve that is misaligned or a valve seat that is distorted by unevenly tightened head bolts will very seriously affect the operation of an engine. The timing will be changed as a result of the valve contacting the high portion first, then later being pulled into contact with the seat by the tension of the spring. The time that elapses between the contacting of the high spot and of the valve being pulled into contact with the seat, while of exceedingly short duration, is really of considerable importance, due to piston travel. Consider an exhaust valve that has been misaligned, or a valve seat that has been distorted by lack of torque control whereby the valve contacts one side of the seat first. This causes the valve to cool more quickly on that side — contracting the fillet — causing the valve to press harder on the seat at one point while the remainder of the valve is cracked open. It is common for such a crack to be opened as wide as .015 of an inch. Therefore, the hot gases rushing out of the combustion chamber pass a portion of the valve only, cause the fillet to expand on that particular side which opens the orifice even wider, further maligning the valve.

Since the gases that pass this leak do not meet the gases that should pass from the side that is closed, they strike the exhaust manifold on one side causing the stream of gas to swirl (see page 11). This will cause a congestion which will prevent the complete scavenging of the cylinder, so that when the piston

reaches the top of the scavenging stroke, there will be a slight compression in the cylinder. This can be compared to turning a high-pressure hose into a drain in a basin. The stream striking the bowl "head-on" will swirl or boil and the basin will fill up and run over. By directing the stream slightly to one side, it will be found that the drain will take care of the flow of water satisfactorily. It is obvious, therefore, that the piston will have to travel partially back down again to relieve this slight compression before the intake of gas can begin (see page 14). This would be the equivalent of shortening the stroke of the engine, with the resulting loss of power, to say nothing of the results that would arise from exhaust gases being left with the combustible mixture that is drawn in with the intake stroke.

This shows the piston at "Bottom Dead Center" just at the beginning of the exhaust stroke. The misaligned exhaust valve is causing the gases to begin to swirl which will cause a congestion in the exhaust manifold and prevent proper scavenging of the cylinder.

This shows the distance of piston travel during the first 45° of exhaust stroke. It also shows the ideal condition with valves in correct alignment. Note the streamlining of exhaust gases for rapid and complete scavenging of the cylinder.

This shows a warped exhaust vaive fully open, intake valve closed, at the beginning of the last 45° of the exhaust stroke. The continued swirl of gases in the exhaust manifold is retarding the rapid scavenging of the cylinder.

Distance of piston travel at the first 45° of intake. Congestion in the exhaust manifold has prevented complete scavenging, leaving a slight compression in the cylinder. The piston must, therefore, move slightly downward to relieve this compression before intake of gas can begin. This is equivalent to shortening the engine stroke.

The piston keeps on Traveling while the valve is sliding improperly off or on the seat

A piston may have completed one-fifth of its travel by the time the misaligned exhaust valve completely contacts the seat. In an ordinary engine a valve is lifted about .001" by the cam, while the fly wheel is traveling from two to three degrees, depending upon the make of the engine. If the valve is cracked open as much as .015" on one side, we therefore would have a piston travel of three degrees times .015", or forty-five degrees of crank travel. Consider this in connection with the fact that when a car is moving at the rate of fifty miles per hour, the reciprocal action of the piston is approximately twenty times a second, and when the valve port is not entirely open all the way around, the piston goes to the top, creates a slight compression as has been previously described, and will return approximately a distance represented by forty-five degrees of crank travel before intake gases can enter the cylinder.


In case of extreme misalignment of both intake and exhaust valves, some of this slight compression in the cylinder may be forced into the intake manifold causing pre-ignition. This is noticeable at higher speeds and is indicated by an occasional cough or backfire of the engine.

Definitely, there is much more to a valve's performance than the function of sealing compression. On one of the popular makes of engines, when the crank pin moves from top dead- center to a point equal to forty-five degrees, the piston has traveled down approximately twenty percent of its entire stroke. The piston in the same engine when moved forty-five degrees from the bottom dead-center will travel up only thirteen percent of its stroke. In other words, the piston is moving a greater distance at forty-five degrees of travel from top dead-center (see page 14), than it does in the same distance from bottom dead-center (see page 12), and it is when the piston is at the top that the exhaust valve is closing and the intake valve is opening. If you will consult late "Valve Timing Data," you will find that in some of the engines the intake valve opens twenty-six degrees before top dead-center and in the same engine the exhaust valves close at thirty-four degrees after dead- center. This means that both valves are open at the same time for a period of sixty degrees.

When these factors are taken into consideration, it must be admitted that misalignment of .001 of an inch on a valve is one of the most important dimensional elements in an engine.

Actual tests have proven that if the ordinary valve struck the valve seat on one side .001" sooner than it did on the other, it would take .010" of clearance between the valve stem and the guide at the bottom of the valve guide to let the valve rest on the opposite side of this seat without bending the stem. Truly then, valve alignment is exceedingly important.

Many service shop operators claim they are perfectly satisfied with the results they are getting. They also claim they are having no trouble. They may not be having trouble, but the owners of the engines they service do have trouble. In most instances they do not know where the trouble exists or where to place the blame, because they have never learned that engine performance can be restored to the equivalent of new after an engine has been run for some time. Many mechanics think because they have .002" or .003" clearance between a valve stem and valve guide they have that much to play with as the valve stem when cold is .003" and sometimes .004" smaller than the hole in the valve guide. This clearance was left there by the engineer to allow for expansion of the valve stem at the top of the guide so there will only be room for a film of oil when the engine is warm and running. There are engines that employ valve guides tapered as much as .004 of an inch, but it was the intention of the engineers that this clearance be reduced to normal clearance when the valve stem itself becomes heated and expands.


In correcting a warped or misaligned valve so it will function properly when placed in an engine, the valve face must be restored to concentricity with the center line of that portion of the stem that operates in the valve guide. Wet grinding is considered a necessity for today's valves and all newer valve facers include a coolant system.

The above illustration shows the effect of holding a valve in a chuck that grips the end of the stem in a cone, and, as indicated by the check marks, in the distorted portion above the guide travel. A valve chucked in this manner cannot be refaced concentric with its original center. Note the valve face is eccentric to the center line of the stem. It is impossible for such a valve to seal compression.

In this illustration we have the effect of holding a valve in a chuck that grips it only on the distorted portion, as indicated by the four check marks. Note the true center line "AB" and the false center line "CD" established by this refacing operation. As this valve is refaced at a tangent to the true center, it will leak compression.

To properly correct a warped or distorted valve it is necessary to grip the valve stem in two places, with a three-point grip, within that portion of the stem that operates in the guide, as shown in this illustration. We know of no other way of accomplishing the proper results. Note that this finished valve face is concentric with the true center line of the valve. The shaded portion "E" shows metal removed. The Kwik-Way Chuck (illustrated below) was designed to accomplish these results. While it has been imitated in many ways, it has never been definitely copied.

Any valve face that is not concentric with the part of the stem that operates in the guide will contact the valve seat on only a small portion of its circumference. It will slap, bounce, be noisy, leak compression and affect valve timing. A properly corrected valve will contact the valve seat throughout its entire circumference and the valve stem will "float" in the guide, free from valve stem friction. Fuel economy and utilization of all possible power will be the result.


The fact that the use of grinding compound will not secure effective results in a valve reseating operation has been accepted for a number of years by the authorities in the industry. It is possible, through the use of compound, to effect a joint between the valve and the valve seat when the engine is cold, but as soon as the valve becomes heated from the natural heat of the engine, the portion that has been ground with compound will not contact the seat due to expansion of the metal. Here is the reason why.- A valve head 2" in diameter heated to 1450° (the normal temperature of an exhaust valve in operation), will expand .016", or .008" from each side of center. This means the valve will rise on the seat. The illustration below shows a valve and seat "ground in" with compound. When the engine is cold the valve and seat apparently form complete contact; but when the valve is heated and has raised, the portion ground in with compound is actually not in contact with the seat at all, and it is impossible for it ever to be when the engine is functioning. Through the use of the Kwik-Way Tapered Arbor for aligning a valve reseating operation, a compression-tight joint may be secured between the valve and the valve seat and this joint will be effective whether the valve is hot or cold. The use of compound on a valve so realigned would really prove detrimental.


Diesel engines occupy a very important position in the service field today. Knowledge of diesel engines should be acquired by everyone in the service industry and as rapidly as possible. In diesel engines of the two-cycle type any tendency for the burned gases to collide or swirl as they are passing out will delay the expulsion and carry the timing over to a point where harmful results will occur, since in this type engine there must be a complete intake of fresh air, compression and ignition in one revolution of three hundred and sixty degrees. In addition, the burned gases must be expelled from the cylinders and the exhaust valve cooled for the next operation. The exhaust valves are cooled while resting on the seat. It is interesting to note that the exhaust valve in a two-cycle engine has sixty per cent less time allowed for cooling than the valves in a four-cycle engine.

A check-up was recently made of a two-cycle diesel engine used in transportation service. This particular engine was operating on a fuel consumption of approximately forty gallons per hour at wide open throttle and at full load, whereas the engine was rated to perform satisfactorily under these conditions on about nine gallons per hour. The engine had been in service intermittently for twenty-three days. As a theoretical analysis of the reason for excessive fuel consumption, let us consider the following:

Upon removing the cylinder heads it was found that the misalignment of the seats was about .01 6". The misalignment of the valves was not checked. Excessive consumption of fuel was the result of valve and valve seat misalignment. The injectors were checked and found to be o.k. Compression appeared normal and the blowers to scavenge the cylinders were producing their normal pressure to blow the burned gases out of the cylinders. In this particular engine the fuel injections take place at 5° ahead of center at an idle speed. The power stroke is complete at about 100°, at which time the exhaust valves open in the cylinder head to permit blowing off the terrific pressure in the cylinder. The exhaust valves are open for a period of


137°. About fifty times the normal capacity of the cylinder at atmospheric pressure in compressed gases has to be eliminated through the exhaust valves, since the piston travels down to expose ports in the cylinder and admit air for scavenging. These ports are open 50° each side of the bottom dead-center. From the time the exhaust valves open and the air ports are exposed by the piston traveling downward, 30° of crankshaft travel has taken place. In other words, when 130° is reached on the crankshaft, the piston has traveled down and exposes the ports in the cylinder and admits air to scavenge the cylinder. These ports are closed by the upward movement of the piston. Then the exhaust valves close and the piston travels up, compressing the gases at a ratio of about sixteen to one.

This particular engine had a maximum r.p.m. of seven hundred and twenty. This means that it made one revolution in 1/12 of a second, and since thirty degrees is 1/1 2th of a revolution, then the equivalent time allotted to blow off the high pressure was equal to 1/144th of a second.

The manufacturer's valve chart shows that the exhaust valves open .008" during six degrees of crank-shaft travel. Therefore a valve that was misaligned .016" or twice .008" would equal approximately twelve degrees of crank travel, partially delaying the opening of valves. Twelve degrees from thirty degrees leaves eighteen degrees, and eighteen degrees would equal 1/240th of a second instead of 1/1 44th as it should have been. In the design of this engine thirty degrees was considered ample time to blow off the high pressure gases. It is obvious if there is any pressure in the cylinders when the ports are exposed that the gases will blow out into the air manifold if the pressure is greater than the pressure in the air manifold or the amount maintained by the air blower. (The air blower maintains a pressure of only three pounds.)

If some of these gases are trapped in the cylinder due to the delay when the exhaust valves close, then if the engine travels around until it gets the next injection of fuel and the resultant explosion is not ample or sufficient due to faulty mixture, the governor will open the injector and admit more fuel. It will explode again on the next revolution and if it still lacks sufficient power, the fuel will be increased more and more which will throw the ratio out of proportion and increase the fuel consumption to a point that will be prohibitive. Since the fuel is coming into the cylinders from one place and the air from another, a very bad situation can occur that would not take place in a four-cycle carbureted engine.

This illustration tends to show the enormous volume of gas that is compressed into the cylinders of a diesel engine — about fifty times the normal capacity of the cylinder at atmospheric pressure.

Remember that the valve seats in this particular engine were misaligned at an average of .016" each. The misalignment of the valves was not checked. With the Kwik-Way System of Scientific Valve and Valve Seat Correction, the valves and valve seats in this engine were restored to proper concentricity and alignment, which sealed compression at the valves. As a result the fuel consumption was restored to the manufacturer's rating which was only about one-fourth of the fuel that had been used during the period of valve misalignment.

It can be definitely seen that if valve misalignment will cause a diesel-type engine to increase fuel consumption from a rated nine gallons per hour to forty gallons per hour, this same condition will to an equal or less extent affect other engines of the diesel type. Again, use of a torque wrench to tighten cylinder head bolts or nuts is necessary to insure against block distortion which can cause misalignment and valve seat distortion.

The engine of today is a marvel of perfection. It will perform satisfactorily in temperatures ranging from one hundred and twenty degrees above zero to from twenty to forty degrees below zero. It has fast acceleration and speed beyond the margins of safety and thousands of miles of satisfactory service. But it has been truthfully said that the engine has not been built that cannot be improved by the service that may be rendered by a well-trained mechanic who uses the proper equipment.

Kwik-Way Products Inc.



Copyright 1948, all rights reserved
Kwik-Way Products Inc.,500 57th St., Marion, Iowa
Revised Edition 1979