Oil Hole for Rear Cam Bushing

Greg Jones

Greg Jones

Well-known member
I had my 26 engine out for a "refreshing". Found that the Stipe 280 cam had seized on the rear bronze bushing and was spinning the bushing in the block. I had the machinist make a new one and he gave it a couple thousandths clearance (actually a skosh less). I am thinking of drilling about a 1/16" hole in the top of the bushing to be sure oil drops in there. Any reason NOT to do this?

By the way, that Stipe cam is the greatest thing I have done to a Model T engine!
 
Im not sure but isnt there a drip hole on the cast iron now? The mains' tops are oiled that way, so I dont see a problem. Can you get a good clean shot at the bearing from the mag coil side? ws
 
Yep I have the block on the engine stand, easy access to the bushing. Original bushings were cast iron I believe and as I recall the end was a little dished inwards, apparently to act as a collection point for oil. Probably could take a dremel and do the same to the bushing but hey, dont want to overthink these things. Also dont want to tear the engine down and find the same problem!

I need to get some photos posted. Just had Simmons in Charleston, SC do some work on the block. They know old stuff and are great. Had them do bronze inserts into the wallowed out valve guides. Great job.
 
My rear cam bushing has a slot cut in the top for that very purpose. Usually we ream the wallowed out guides to the next oversize and put in oversized stem valves. No need for guides.
 
The brass bushing should be 1.520 thousandths long.


It should be .215 thousandths cut in from the top, and .180 thousandths in from the end.

The middle of the notch, to the other end should have a stright oil groove cut in it, about 1/8th wide.

You should use a bushing driver, put it in flush to the inside, and the notch goes towards the lifters.

On a .748 shaft, the hole should be .750.

The bushings can be made out of old triple gear bushings.

Herm.
 
These valve guides were way wallowed out due to a well meaning "mechanic" reaming the guides to accept Chev 350 valves. I could kick myself for letting him touch the engine as I believe he reamed the guides using a reamer in a handheld power drill. He convinced me that the 350 valves were the way to go, had done it a million times he said, and I left my car with him to have at it. Didnt know he was going to do it by hand like that. Let's just say he was off a few thou, to say the least, and sure did not maintain a straight line.
 
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