The Stovebolt Site Forums The Shop Area Engine Shop Cannot "stab" new distributor in 235

Well I got the brakes done and then I discovered the hard way that my old points and condenser were giving me fits. So why not upgrade to a new HEI distributor while I have it tore apart. So I got the new distributor and, just to be sure, I compared the shaft, cam gear and the flathead end that goes into the oil pump against my old one. Everything looked identical. So I lined up the ears on the oil pump as close as I could and put the distributor in place. I rolled it over and it started right away, but 0 oil pressure so I shut it down quick. 3 hours later, probably 50 attempts to "stab" it and engage the oil pump and no dice. Tried jogging the starter, making multiple attempts of tiny adjustments on the oil pump shaft, no luck. There are no obstructions outside, there is plenty of clearance all around. The hold down bracket is completely loose and out of the way. I'm totally stumped.... Any ideas on what i am missing? Is it really that hard to get the oil pump shaft just right?

Forgot to mention it is a 1954 235 engine.

Did you check the thickness of the drive tank on old and HEI distr? I suppose the HEI one is thicker. If one can turn the engine with the fan or in high gear, one could rotate the engine that way while pushing down gently on the distr.

Good luck.

Ed

If your engine starts that would indicate that the dist drive gear is properly engaging the cam gear. Have you measured the length of the shaft from the bottom of the dist gear to the end to see if it's long enough to engage the oil pump? Any possibility that the oil pump or gauge is bad? Maybe insert dist, turn over a little by hand then pull dist to see if oil pump slot has moved. That would verify whether the oil pump is being engaged or not.

Thanks for the replies.

The shafts are the exact same size, diameter and length.

When I turn the engine over the oil pump shaft does not turn.

It fired right up immediately.

Part of the distributor gear will mesh with the cam gear before the end of the shaft engages with the oil pump, allowing the engine to run.
I would use a shaft with the same tip on it as a distributor and do a test fit to make sure that it will engage with the oil pump.
If it does, then keep trying to line it up with the distributor. You need to make sure that you allow enough lead-in in the placement of the oil pump slot due to the rotation of the distributor as gears engage and rotate.

Thanks for all the replies. I got it sorted out. The culprit was.... the rubber O-ring!! Just for fun I took the o-ring out and it went straight down in. So I put some oil on the ring and tried pushing down hard and the ring would just not collapse enough. So I used a gasket and Right Stuff instead. I'll see if it leaks.

Never- - - -ever- - - -use an O ring on a distributor, even on the point type if they have a groove on the housing. Yours is not the first "no oil pressure" experience I've heard of caused by an O ring. On the original equipment distributors, an O ring can create just enough drag that the vacuum advance can't move the housing quickly enough to respond to manifold vacuum changes. That can cause a detonation rattle while accelerating.
Jerry

Rubber does not compress, it distorts.

Ef

Glad you found it. Hind sight being what it is the better approach maybe would have been to use a screwdriver in the pump slot and measure to the deck of the block. Then mark that distance on the distributor body to see if it is going in far enough. Anyway maybe these posts will help the next stove bolter who has a similar problem!

I agree - hopefully someone in the future will find answers here. I spend a lot of time searching prior posts before I attempt anything major, or when I get stumped. I wish Hotrod Lincoln would publish a set of books or a website of mechanical experience - the years of real world knowledge makes life way easier.

You read my mind Chad. I'd like to see him write a book of all of his quick hitter tips, including his patented colorful delivery.