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Wes;
As you know I've had the oil pump out and the engine has been rotated, so it's out of time. I'm waiting for oil pump gaskets, I thought I'd get this question out of the way. The only reference I can find anything on this is a CJ2A service manual.
So to time this thing, I bring it up TDC, insert the oil pump with the off enter slot at a 9:30 position and the wide side in a up position and push it onto the cam gear and bolt in place. To confirm correct installation I look down the distributer shaft hole with a light and confirm the slot is now in an 11:00 position with the wide side in an up/top position. Is this correct? Thanks Dean.

You should always say jeep model before you ask a question. The easy way to not have to remember to ell us which jeep or engine you are asking about is to include the Year, make and model of your jeep or jeeps in your signature block.

The reason for making sure the relative position of the oil pump and distributor are correct is to ensure you have adequate room to swing the distributor body to set timing. Technically you are suppose to remove the front timing cover and align the crank gear timing mark with the cam gear timing mark while #1 is TDC on Compression (not exhaust).

This procedure is covered in great detail in the TM 9-8015-1 for the M38A1 and TM 9-1804A for the M38. This is one reason to tell us which jeep you have.

The other reason is the configuration of the spark plug holes vs the piston in the L-134 vs the F-134. They are not the same. You can within reason accurately get the F-134 to TDC on compression using a rod or a timing dial indicator because the plug hole is above the piston. The M38 plug hole is above the valves. Therefor you need to fabricate a wiggler to tell when the piston is TDC. Keep in mind that the crank will move about 3-5 degrees at the TDC area without moving the piston. This is the flat or dead spot. Therefore you should note when piston up travel stops by making a chalk mark on the crank pulley and then continue until the piston starts to move down and make another chalk mark. Then split the difference for a true TDC.

Or you can get #1 piston TDC on compression with the oil pump out. Then referring to your timing tab back the piston up to 5 degrees before TDC. Then insert your distributor which already had it's point gap set on the bench in the block with the body about midway from the block. Turn your rotor towards the correct #1 position. (If you have a M38A1 and are using TM 9-8014 to set the distributor then be sure to use the latest change which corrects the illustration of the #1 wire position on the cap.

My photo album and in particular the Ignition album is helpful here.
http://www.willysmjeeps.com/v2/modules. ... _album.php




This is the erroneous figure in TM 9-8014 that I have corrected.

Now using a small piece of paper set your timing the old fashion way. With the distributor installed and rotor pointing to #1 wire set the cam follower just before the before the points will open at #1 firing position. Insert the piece of paper between the contacts and maintain a soft tug on it. Now very slowly rotate the housing towards retard until the paper slips free. Stop. Now get on the other side of the jeep and eyeball the distributor shaft tab position through the oil pump hole. Now match your oil pump's shaft to the distributor's shaft position. Then recheck timing the same way again.

By the way Wes, it's a 134F with a timing tab spot welded onto the timing cover. Is it original, who knows. I'll give it a shot. I think i have enough information. Thanks

If you click on your profile and enter your jeep model and year in the block near the bottom titled "Signature" you will always have the needed reference data posted with your post. If you add your first name there as well we can all then be on a first name basis instead of this CB handle basis!