i'm converting from a mechanical fuel pump to a electric pump. do i leave the push rod hole empty or do i need to plug it, will i lose oil pressure by leaving it empty?
You will not loose oil pressure unless the bushing is worn through and there's a hole in it. In a properly functioning oil system, the oil flows through the galley *around* the bushing. Bob
They made flatheads for several years, and arrangements differ... Some late engines have a tiny oil hole in bushing, probably sufficient reason to plug the hole...perhaps a cup plug top and bottom. On earlies and on late ones without plugs inserted it is probably worthwhile to leave in a piece of pushrod in bushing supported above contact with cam to prevent the possibility of oil misting out there. Valve chamber does not like any extra oil from anywhere. If early, leave in tube baffle below pump stand to shield filling stack from excess oil fog.
When I installed the blower on my '49 Merc motor I had a lot of vapor coming out of the oil fill/breather on the back of the intake manifold. I all ready had an electric fuel pump. I removed the oil fill/breather tube and looked in the hole with a flashlight. A lot of oil pulsing into the valley. I bought a 3/8" Welch plug at NAPA, stuck it on a piece of all thread with RTV. Reached thru the hole and tapped it in place; problem solved. This would be a motor that Bruce mentioned that had the small hole drilled in the bushing. Jim
Basically something needs to be in the hole, either a plug or a facsimile of the rod. Correct? And it sounds like the original tubing baffle should be there if it is a non-8BA block. Is that it in a nutshell?
Yes. On late blocks with the oil hole, flow should be insignificant there, issue is blocking any extra paths for oil into valley. Seems like the gravity system non-seals at valves can handle nothing beyond the original amount of oil fog and splash... I think rod fcsimile is a good way...
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