How do you adjust valve stem clearence of stock valves with stock lifters?

[walt jones]

Now that we have delt with the Model A valve grinding question. What methods can be used to properly fit the length of the stock valve stem, including proper clearence from the seat to the stock non adjustable lifter?

[Russ/40]

Simple, lash too tight remove material from the valve stem. Lash to big, grind the seat to drop the valve deeper.

[Patrick L.]

Yep, what Russ said.

To increase lash, grind the stem end. Thats what the micrometer thingy on the end of the facing grinder is for.

To reduce lash, grind/cut the seat. The seat could then end up being too wide requiring narrowing.

[colin1928]

Normally after refacing valves and seat you will need to remove some material from the stem best done with a valve refacer with stem grinding attachment
for gaps that are to large I prefer to take some off the valve face and leave the seat alone easier to replace valves later then seats

[Patrick L.]

Originally Posted by colin1928

Normally after refacing valves and seat you will need to remove some material from the stem best done with a valve refacer with stem grinding attachment
for gaps that are to large I prefer to take some off the valve face and leave the seat alone easier to replace valves later then seats

Thats a valid and easier way to do it, as long as there is enough margin left.

[walt jones]

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I understand that material must be removed from the valve stem in order to set the correct valve lash. The valve grinder that I have access to is very old and it does not have an attachment for grinding valve stems. I am wanting to find out other methods that can be used to grind the vave stems for proper lash? Possibly even "non standard" or patent methods.

[Tom Wesenberg]

You could make a V block and set it up next to your grinder so the stem can be lightly ground from the side of the stone. Use your finger on the head of the valve to spin it as you grind it, and use your other hand to hold the valve in the V block. Take light cuts and measure often.

Use a fine grit wheel.

[Patrick L.]

A homemade jig could be made as Tom suggests. Several comments have been made recently regarding this.

There could be a valve grinder/face machine in your area either in an old auto repair facility gathering dust in a corner, or, at the nearest aircraft repair facility at your local little airport. The one at the airport is probably still being used.
If there is any clearance at all on each stem then a measurement can be taken and used to get a proper lash when taking those valves to the machine. If you become friendly with the machine owner you may be able to take it home for a couple days. Most old time mechanics are pretty friendly folks.

[H. L. Chauvin]

Article I wrote about (15) years ago on other Forum Site:

Question: "How do you adjust the clearance with the original lifters?"

Anyway: For Original Valve Adjustment - Quiet Valves

1. When one did not have a special valve tool, here's one way it was done by many Model A era mechanics.

2. Because of working with thousandths of an inch, it was best to use a hand crank emery wheel, (grinder), with a very fine "pink" stone, such as that used to sharpen delicate scissors.

3. Next make a wood, valve holding jig out of a 1x4, with two vee cuts in these two vertical pieces of wood, (maybe 3" high), to rest the valve in horizontally.

4. Secure these two vertical wood vee jigs to a 1x4 horizontal plank, (maybe 12" long), & make sure that the valve will be set parallel to the bottom plank so the valve will be level with the top of the work bench, and more importantly that the valve will be set 90 degrees horizontally to the vertical "side" of the grinding wheel.

5. Next securely clamp the hand cranked grinder to a work bench, use a small carpenter's square to set the valve in the valve jig at 90 degrees to the side of the emery wheel, (both vertically and horizontally), and securely clamp the wood jig to the work bench.

6. Measure both 90 degrees carefully.

7. By securely holding the valve in the vee, and letting it firmly touch the side of the grinder, remove very little from the end of the valve stem, (if required), and try for clearance.

8. If one removes slightly too much off of the end of the valve stem, one can re-lap the valve with valve grinding compound to make it sink slightly deeper in the block to get proper clearance between the end of the valve stem and the original lifter.

9. We always used .011" clearance on intake valves and .013" on exhaust valves for "A" & "B" engines, (with or without high compression "Original Police" heads), an never had a problem -- "never" -- and never had valve noises.

10. Its amazing to see the accuracy that can be mechanically achieved without having digital measuring devices, radar, fiber optics and atomic resources -- just a little common sense and a little patience is all one needs.

H. L. Chauvin
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Then Mr. Marco responded:

"That's one of the advantages of original tappets. They provided a cushion of oil on the top of the tappet. The small size and domed top of adjustables cannot provide that cushion."

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Couple of added tips:

A. Most with no experience get aggressive and remove too much metal from stems ...... lots of work to grind seats to close too large a gap ....... we are talking about thousandths of an inch.

B. Best to place valve stem on the side of the hand grinder that is moving downwards instead of upwards; i. e., pushing down on the tip of the valve stem set in wood the wood vee.

C. Push down on side of valve to hold it in the wood vee at 90 degrees.

D. Valve will "very, very, very" slowly rotate when valve is set at 90 degrees; however, "if" valve rotates more, this indicates that the valve is not set at 90 degrees, and that material is being removed from the outer circumference and one side of the stem, where when completed, the bottom of the stem will be round in lieu of flat.

E. Valve jobs done like this on a rebuilt engine should last over 50 years with no further adjustment ..... mine did ....... still have engine I rebuilt over 50 years ago and ready to re-install in my 1930 Coupe ....... detergent oil religiously changed every 500 miles may sound stupid ....... but ...... it work wonders ...... and not to mention, it also hurts the Model A parts suppliers' businesses.

[walt jones]

Thank you H.L., Tom and all who responded. Information aquired here is being used to referbish a Baldwin/ Gleaner combine engine for the MAFFI Museum.