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Tappet Problems on the Lister type Engine 

Quality on these engines is good in areas where it has to be. Fits on connecting rods, pistons and all critical engine parts is very good.  

But, some of the outer less critical fittings can leave a little to be desired.

One of these are the valve lifters (ie tappets). On most engines they rotate properly and give no problems.  On a very few however they do not turn. This turning serves two purposes. first to reduce friction to the up coming cam lobe (like a wheel) and to distribute ware to the lifter face evenly.

As I said before most engines work fine and will give no problems. Also with as low of valve spring pressure and the low cylinder pressure when the valves are opened I dought that the lifters will fail with normal daily use, due to this non rotative problem.  I tend be over critical of such things. I feel that things like this should work.

So.

All a person has to do is keep and eye on them. I put a zip tie around each push rod and trimmed it short so if the zip ties it turning the lifter is turning.

Remember if you buy something from me I will work with you to help fix any technical problems.  

Here is a list of reasons I have found lifters fail to turn.

1: Lifter face is not at a right angle to the lifter shaft.  Can be reground at most auto machine shops or sent to me for service (This occurs when the part distorts in the heat treatment phase of production.)

2: Machining burrs are left on the lifter shaft from cutting the oil slot    (These can be cleaned with a small file or oil stone)

3: Lifter Body Is not within .015 of perpendicular to the cam lobe  ( Replace lifter guide )

4: Lifter body is over .015 nonconcentric to lifter bore.  ( Turn lifter guide till lifter rotates the best, re-drill oil hole in lifter guide to mach new position)

5: Cam lobe installed on cam shaft too close to center line of lifter  ( Hard to fix still working on this one)

6 Reduced friction between cam and lifter due to extremely hard lifter and cam facings and better lube oil properties   (conjecture on my part  I am researching this further) May require tempering of lifter face.

It is my recommendation to remove all the paint from the lifter. this can be done with a pocket knife or gasket remover spray.

It is also my recommendation to remove the both  lifter guides and place a center punch on the outside of the guide opposite the oil hole in the guide. When the guides are replaced the punch mark should point out and the oil hole is pointing into the engine.  

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