I rebuilt a SBF replaced the oil pump turns out the relief valve was stuck 10w30 oil and priming with a speed handle I could peg a 100psi gauge with ease. There was no way I was turning the pump 100rpm so think how much of the time the relief valve is open. Pumping oil takes horse power.
Not for a long time but yes. I’m not sure how that relates to my post but ,,,, here goes a wild guess - one side of the crank is going up just as fast as the other is going down.
It ac***ulates in the rocker arm covers. I had the problem with a 327 Corvette engine (that the "rebuilder" did me the "favor" of installing a high volume/high pressure pump). The oil drain-back p***ages in the heads couldn't handle the volume of oil pumped onto the heads and it also burned a lot of oil. Replacing the pump with a QUALITY GM pump solved all of my problems. ( I have been su****ious of "Mellings" oil pumps since then). If your new engine "pegs" the oil pressure gauge CHANGE THE PUMP.
Them pushrods and rockers sure must have been having one hell of a party to fill up the rocker boxes. Enough to overcome both of the drain holes that are 5 times bigger. I’d put my money on a filer getting jammed up with oil and a relief valve getting stuck.a controlled leak out of control. But hey,, y’all may have found the place where all the oil goes
I also made the mistake of using high volume pump. On long run's using higher than normal rpm's (going faster than allowed) it goes out the tail pipe. Drive normal no need to add oil afterwards.
I hate to say this, but you're wrong. I went through this in real life, and it took several weeks to burn off all of the excess oil that had inundated the engine. I was the guy under the car, dropping the oil pan, and replacing the pump. My filter was fine, thank you. ('67 Corvettes have a cartridge filter).
From Melling. Oil pressure problems The first reaction to an oil pressure problem is often to replace the oil pump- sometimes unnecessarily. Since existing problems within the engine can’t always be fixed by installing a new oil pump, you should carefully evaluate the situation before doing so. An engine could have oil pressure problems for many reasons: An air leak (usually where the screen is mounted to the pump). Check for loose connections, cracks or holes. Since air is compressible, any air inside the oiling system can cause a fluctuation of pressure. Too much oil in the crankcase (leading to air in the oil). Excessive clearances within the engine (rod and main bearings, cam bearings, seals and oil plugs). Oil leaking past the mounting pad area (usually caused by tightening the mounting bolts wrong). Malfunction of the relief valve ***embly. As we mentioned before, the main function of the relief valve is to regulate oil pressure within the engine by keeping a constant flow of oil to the engine. There are three different relief valve problems ( usually caused by foreign material that is drawn into the pump from the engine) that can cause oil pressure problems: The relief valve is stuck in the closed position. It won’t let extra oil pressure release itself inside the pump, so the pressure builds and ruptures the oil filter. The relief valve is stuck in the open position. The pump will release too much of the pressure, creating low oil pressure and possible bearing failure. The relief valve is sticking, so movement of the valve within the ***embly bore of the oil pump may be restricted. In this case, the valve isn’t necessarily stuck in a fully open or closed position, and the result is erratic pressure. Since oil pumps are manufactured with such close tolerances, it doesn’t take too foreign material to cause problems with relief valve operation. And it’s easy for dirt, bits of wire, etc. To get into the oiling, even with the screen ***embly in place. So, be sure to find the root of your oil pressure problem before you decide to replace the pump. Or start thinking your valve covers are full of oil starving the sump
Your oil pump has the pressure relief valve. The filter can handle X amount of flow before it backs up. Begin stuffing more flow than X into the filter and the pressure builds.
OK, have it your way. I think, however, that just about everyone that has posted on this thread seems to agree that, unless you are building a racing engine with designed larger than normal bearing clearances, anything other than a stock spec pump is a bad idea.
Different engine same issue , my 32 has a 302 Ford engine in it . Built to blue print specs . The machinist told me to use Ford HP pump and Motorsport pump drive shaft . I did as he suggested . It carries 80 psi plus traveling at 60 mph . It was a Boss 302 HP pump . I have no idea what the pressure is at 60 mph , the gauge only reads 80 psi and it’s resting on the stop . It has been this way for many miles and years . Is it needed NOWAY ! I’m I taking it apart to change the pump no way . I always used the big block pump in my small cube Chebby engines with the pick up brazed on . Never one issue . Mellings is or was a great product , I would use them in the future . I think from my engineering days on a hydraulic system , oil or any liquid is non compressible , so increasing pressure also increases volume , and increasing volume will increase pressure . If that makes any sense to any of us . As said it’s all about clearances, a good fresh accurate built small cube Chebby , should live many many a hard driven mile with a stock pump . One thing no one has said a word about is the nylon sleeve between the pump and drive shaft . I’m sure OEM will be fine but in my Chebby days I always used the best as I could locate and purchase , is it needed ? Depends on if your running a HP or HV pump !
Here is a recent photo with of the dash area of my 32 at near 60 mph , check out the water temp and oil pressure . This is the effect of super tight to spec clearances and above stock oil pump . Is this needed HELL NO , is it hurting anything HELL NO ! There are many miles on this engine at this rate , not one issue to date .
Hard to see, but the temperature seems to be a little low and the oil pressure seems a bit high. Out of idle curiosity, how's your oil consumption?
Anybody want to get back to "BIRD'SGARAGE'S" problem instead of batting gums & t******* their chests about their pump "wins" & "losses"?? There's obviously something else going on in his motor that's showing up as a pump problem, but his pump problem is a SYMPTOM, NOT the actual problem, so what is it?? Any ideas??
Please take note of the ***le of this thread. I have had a real life bad experience with HV/HP oil pumps and would hope I could save others the same experience.
I'll add this; use an aftermarket oil pump drive rod with the steel collar. The nylon collar can and does break with age, and that can lead to breaking the drive shaft on the pump; then you have NO oil pressure as the drive rod falls out. I am Butch/56sedandelivery.
It’s been covered,, Go with Stock pump And a malfunction in the pressure relief spring. Unless you’re subscribed to pumping the pan dry
You spend money to gain hp and give it back with to much oil pump and to much valve spring pressure doesn't make sense.
I thought I read the other day somewhere the oil pump uses 2 to 5 per cent of engine horsepower. Sounds like a lot to me, but I suppose that's right in there maybe. I also read that it's the oil flow that counts. High pressure isn't necessarily a good thing.
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