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Wedge Funny oil pump

Dale

Jedi Knight
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I didn't turn up anything similar in a cursory search, so, I'll ask for any input regarding an oil pressure light that goes out at idle and gets brighter as the RPM rise. I have installed a new sender with no change. Is it possible that the hex shaft that drives the oil pump from the bottom of the distributor is worn round and skipping? I appreciate any and all input. I am, of course looking for the quick and easy, but feel free to share any thoughts you might have.
 
Are you sure the wiring to the sender is good?

My first thought would be to double-check by connecting a gauge. Most aftermarket mechanical gauges come with an adapter that will fit where the lamp sender goes, and for a temporary test you can just lay the gauge some place where the line doesn't touch the fan or exhaust manifold. Lots cheaper than an oil pump.
 
Are you using a spin on filter? If using see if it has a by-pass. If using the canister original, might check by-pass valve spring in housing. Check the sender for voltage increase or decrease while running.
 
I had similar behavior with one oil filter on the Herald. At idle, good oil pressure but then as the RPMs went up, the pressure gauge just went crazy swinging from about 15-50 psi. A new oil filter solved the problem. It seems that the spin on-filter I used just had to low a relief spring. So if you have a spin on filter try replacing it (maybe with a different brand / model) if not check the bypass.
 
Thank you all for the prompt and encouraging replies. The test gauge suggestion is the one I was supposed to have done two months ago, but got lazy. Will get on that next. I have persisted with the canister filter (tradition you know) and have changed the oil and filter and cleaned the bypass gadget. Will tackle it again in a couple weeks when I quit flitting about the country. Thank you again for the replies and I will let you know what transpires.
 
Had a similar experience with a SBF, good OP at low RPM's, but decreases as rev's increase. Turned out to be bad bearings. Hope that isn't your situation.
 
I had this problem on a build SBC. Everything was brand new. I had a winged oil pan so I was running 7 quarts. My pump was measured by be to be the correct distance from the bottom of the pan. I fought this for a year. I thought the oil was staying in the top of the motor and the little in the pan was sloshing. Nope. I thought the oil pump shaft wasn't pushed in all the way and was slipping when I hit the gas. nope. I thought the composite gear on my dist was wiped out causing the oil pump shaft to not spin when I massed the pedal. Nope.

What it ended up being was too much oil. The crank would smack the oil and cause cavitation sending air into the system. I didn't have awindage tray or crank scraper. I drained the oil and put in 5.5 qt's. Then I put in a little more until it dropped psi upon hard acceleration. Then I drained a little and all was good. No more psi drop. Too much oil causing froth.
 
I would first check pressure with a mechanical gauge. Then I'd ask if you have a sender for a gauge in there. That will do that, won't it? Higher pressure more grounding (less resistance) and brighter light?
 
No reply. The reason I suspect a gauge sender for an idiot light is it will do that. Exactly that. High ohms at idle, less as speed increases. Idiot light may be out or glow at idle, and resistance in sender decreases with pressure, light glows brighter and brighter.
 
No reply.
Well, he did say he was "flitting about the country". Might be he hasn't had a chance to see your post.
 
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