Low oil pressure at higher RPM" New Motor BBC"
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Low oil pressure at higher RPM" New Motor BBC"
I purchased a 454 from a guy in KC he had it built for his boat by a shop near him. All New parts 30 over 8qt oil pan, roller rockers, the works. Sounded like a good deal at the time. Bottom line it sat in his garage covered up for at least a year dry, no oil in it besides assembly lube. I got it in my boat and it has 60 psi at idle sounds great idles like a dream. If taken to 2000rpm, with in 10 seconds it will drop to 15 and sometimes 10 psi. Let off and let idle it comes back to 60 psi. At first I thought He installed the wrong dipstick because of the oversize oil pan so I added 2 qts oil. Didnt help though it did the same thing.
IS THE OIL PUMP BAD?
I was thinking since it sat for a year with condensation maybe rust built up in the oil pump causing springs to stick or something. What is your opinion? Any Ideas? What should I do?
IS THE OIL PUMP BAD?
I was thinking since it sat for a year with condensation maybe rust built up in the oil pump causing springs to stick or something. What is your opinion? Any Ideas? What should I do?
#3
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Just something to think about. Does it have too much oil in the pan?
If so, this can cause the crank to whip the oil, causing the oil pump to cavitate. Especially if you added two more quarts to an already over full pan. If the oil lever is correct, it sounds like you'll have to pull the engine and inspect/ replace the pump.
Darrell.
If so, this can cause the crank to whip the oil, causing the oil pump to cavitate. Especially if you added two more quarts to an already over full pan. If the oil lever is correct, it sounds like you'll have to pull the engine and inspect/ replace the pump.
Darrell.
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Yes I pulled the distributor and primed the system before break in.
I didnt think about having too much oil... What does a stock 454 take to fill with oil? and there was a over size oil pan installed I was told it was a 8qt pan.
I didnt think about having too much oil... What does a stock 454 take to fill with oil? and there was a over size oil pan installed I was told it was a 8qt pan.
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well... before i did any of that, i think i might put a mechanical gage on it and check whats going on for real.
think about it... the pump is a simple positive displacement device. you say it pumps up to 60 at idle... to me, that means the pump works fine. now... if it overpressures, then the relief valve is supposed to pop off but thats only going to bleed off excess... so you would still see 30 or so.
so you rev it and it falls off but when it returns to idle the press comes back... to me that sounds just like what you said... low oil level or maybe the pickup has broken off. or once in my life, i saw a bad oil filter do this ( also one plumbed backwards. ) but for me the bottom line is that at idle it makes pressure. that is the "worst case" time for a hydraulic system... low pump speed ... because pump speed and volume are linear.
i think i would look at the gage sending unit before i went crazy
think about it... the pump is a simple positive displacement device. you say it pumps up to 60 at idle... to me, that means the pump works fine. now... if it overpressures, then the relief valve is supposed to pop off but thats only going to bleed off excess... so you would still see 30 or so.
so you rev it and it falls off but when it returns to idle the press comes back... to me that sounds just like what you said... low oil level or maybe the pickup has broken off. or once in my life, i saw a bad oil filter do this ( also one plumbed backwards. ) but for me the bottom line is that at idle it makes pressure. that is the "worst case" time for a hydraulic system... low pump speed ... because pump speed and volume are linear.
i think i would look at the gage sending unit before i went crazy
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Is that 60 at idle with hot oil or cold oil? 60 at cold start up is low. Mine reads 90 at cold start up and 60 hot cruise. Try running with 6 qts. That's still plenty to test with.
Last edited by PatriYacht; 06-01-2009 at 01:27 PM.
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"plumbed backwards????????"
That could be a possiblity? Is there a schematic anywere, or can someone tell me exactly how to run all the oil lines, just so I can Make sure I did it right?
That could be a possiblity? Is there a schematic anywere, or can someone tell me exactly how to run all the oil lines, just so I can Make sure I did it right?
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Oil goes out of the engine to the filter and cooler from the outside of the filter pad. It goes back in thru the center of the filter pad. If you take a close look at the adapter on the filter pad you can see that one hose is off center.
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