High volume oil pumps
#1
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Discovered my oil pump pickup lying in the bottom of my pan this weekend. Believe it or not, rattled loose during a 5 hour trip on the FREEWAY. Was even tig welded in place.
I will be replacing it with a new one, but I've never shopped for one. What's a quality brand? High volume or not? Looking for 55-60 psi. This is 502 Gen VI BBC, HP500,
Thanks,
Brian
I will be replacing it with a new one, but I've never shopped for one. What's a quality brand? High volume or not? Looking for 55-60 psi. This is 502 Gen VI BBC, HP500,
Thanks,
Brian
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Melling pumps are good... and reasonable in price too..... but... don't tig weld on the pick-up... silver solder it.... Cast iron doesn't like welding. Silver solder looks like brass... but melts at a much lower temperature.
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Reed makes a good point about avoiding excessive heat. You can tell if you've put too much heat in and caused warpage. It will be more difficult to spin the oil pump and there will be tight spots. For what it"s worth.
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I've had better luck welding a small strap to the pickup and using one of the bolts on the body to secure it. Mine fell off after tigging it and scrapped my fresh engine. Another expensive lesson learned.
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My engine builder also tells me he used Melling. How critical is the pickup height from the pan bottom? 3/8" measurement will be difficult fto check for a couple of reasons: 1) how do you measure with the pan in place? 2) engine is dangling on a chain in the garage, and the pickup will be welded/brazed at my builder's shop. The oil level is 3 or 4" above the pickup when full, so why the critical height?
Luckily, I didn't trash anything. Ran great with good pressure on Friday, so I put it on the trailer and headed South. Fired it up on the trailer Saturday morning at the boat ramp, and no pressure. Thanks to oil pressure switch cutting power to my electrical fuel system - saved my a$$ again!
Thanks for the input,
Brian
Luckily, I didn't trash anything. Ran great with good pressure on Friday, so I put it on the trailer and headed South. Fired it up on the trailer Saturday morning at the boat ramp, and no pressure. Thanks to oil pressure switch cutting power to my electrical fuel system - saved my a$$ again!
Thanks for the input,
Brian
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I'm with kennyo.I had on break at the pump so I started welding a strap that bolts to the housing on the last few engines I have done.
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Brian-- These guys are giving you good advice. Keeping the pickup 1/4 to 3/8" off the pan bottom will keep the pump from sucking air when you're at high RPM or the boat is turning aggressively or rocking and rolling. There are many ways to check the gap. Obviously it's easier on an engine stand with the motor upside down. If the motor's hanging, you might put spacers of different thickness in the bottom of the pan and try bolting up the pan. You'll quickly find what the gap is. If the motor's upside down, you could put a straightedge across the pan mounting surfaces and measure to the bottom of the pan. Then measure the distance between block surfaces the pan bolts to and the pump pickup at its lowest point. Compare the two numbers and you have the gap. When the pickup is properly oriented on the pump.the pump can be removed and welded at the shop. I hope this helps.
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