Extreme oil pressure
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Extreme oil pressure
I have a BBC Merlin 3 block, when I prime it with a drill, I am getting ungodly oil pressure, wrapping the needle on a 100 lb gauge and slamming it back on the 0 peg. I took the oil pump off and double checked the bypass valve and it works free. Any ideas what could be causing this excessive oil pressure?
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I have a BBC Merlin 3 block, when I prime it with a drill, I am getting ungodly oil pressure, wrapping the needle on a 100 lb gauge and slamming it back on the 0 peg. I took the oil pump off and double checked the bypass valve and it works free. Any ideas what could be causing this excessive oil pressure?
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I have a BBC Merlin 3 block, when I prime it with a drill, I am getting ungodly oil pressure, wrapping the needle on a 100 lb gauge and slamming it back on the 0 peg. I took the oil pump off and double checked the bypass valve and it works free. Any ideas what could be causing this excessive oil pressure?
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Absolutely I agree it will wear stuff prematurely, I am pulling the motor in the AM, just looking for ideas on the cause. I am down to the pump bypass sticking or there is a blockage after the oil comes out of the motor, that woild go to remote filter and cooler and then goes back in to the block. I bypassed the filter and cooler with AN unions, because it was blowing the filter of the remote mount, I wanted to eliminate that piece. The oil is 20w50, the main clearance is .0025, the rod clearance is .003. It is definitely way out of line.
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Apparently the problem was the oil pump, removed it and replaced it with another pump, and walla, 80 lbs on the drill. I can't believe that the pump was the problem, it was the Melling 10777, I would have to surmise that even though the bypass worked free that it wasn't opening properly. Thanks for the input.
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Apparently the problem was the oil pump, removed it and replaced it with another pump, and walla, 80 lbs on the drill. I can't believe that the pump was the problem, it was the Melling 10777, I would have to surmise that even though the bypass worked free that it wasn't opening properly. Thanks for the input.
Did your pump only have the pin & spring in it only? I always test my pumps in a tank with a pressure gauge before installation, saves alot of oil pressure differences between engines after assembly. I would also expect to see mains around .0032 and rods around .0025
Glad you found out the problem, before you had alot of problems. Mark