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  #16 (permalink)  
Old 01-06-2004, 09:17 PM
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Quote:
Originally posted by MI2600
I would be leery about using a high pressure pump. We used one on a 350 rebuild. During cam break-in, at 2000 rpm, we had about 80# of pressure!! It caused more problems than it was worth, in terms of leaks, etc, and I finally put the standard spring in.
I would say 15#-20# pounds at idle is ok. As stated above a lot depends on the quality of the gauge.
There is nothing wrong with running a higher pressure pump. It could be argued whether or not it is necessary, but there are no ill effects. The leaks had nothing to do with the oil pressure.

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  #17 (permalink)  
Old 01-06-2004, 09:38 PM
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I failed to mention in my previous post that my Dad's engine is brand new too, with about 50 miles on it. So it wasn't like the bearings went bad then the pump. It was due to new Sealed Power oil pump. Beware!!!
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Old 01-06-2004, 10:11 PM
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We just finished 2 engines, both using the standard Melling HV55 oil pump and we each had 64 pounds of actual pressure using a drill on the primer. My current engine runs at 70+ cold and 50 hot and it has 140,000 on it with the Melling pump. Those numbers sound pretty low to me, given my experiences.

About all the high pressure pumps do is take alot more horse power to run.

Mark
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Old 01-06-2004, 10:30 PM
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Did you build this engine yourself? I agree the oil pressure is low and I would be concerned. In a fresh tight engine it should not be that low.

Does the noise you hear go away if you get the RPM's and oil pressure up (maybe 2000-2500RPM?).

There is a 1/2" plug that goes under the rear main cap on SBC engines, these are often over looked and would cause you to have low oil pressure, this would also cause the noise you hear (because the crank is not getting enough oil). Do yourself a favor and pull the pan and have a look at the bearings. If you catch it early enough you won't have to turn the crank and it will save you time and money. However if you wait you run the risk of chewing up the crank and getting metal through out your engine.

10psi per 1000 RPM is a rule of thumb and I agree with it. The problem is the noise along with the low oil pressure, that tells me something is not right (IMO).
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Old 01-07-2004, 08:26 PM
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Oil pumps.

High pressure and high volume are 2 different topics. If you go threw this post, I do not think everyone is on the same page.

I`ll admit that my high volume oil pump still scares me. BUT. If you talk to some race engine builders they say lower pressure pumps use less horsepower. ( I know a few of you guys do build race engines )
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Old 01-08-2004, 03:51 AM
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12-17 sounds normal. As an example some pontiac V-8s use to only get 6psi at idle.
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Old 02-13-2004, 12:48 AM
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Starting problems on sbc 350

Hey guys....update on my oil pressure and knocking problem. I changed the oil to Castrol 20w50 and put on a K&N oil filter. My pressure is now 25 to 30 at idle and around 40 cruising. As for the knock, it was the torgue converter. Darn thing wasn't tight enough. Imagine that!!

Now I have a new problem. Now the darn thing doesn't like to start after driving it for a few miles then shutting it off. I recently replaced my OEM starter with a Powemaster high torgue mini starter. After charging the battery the motor will start just fine. I have a volt meter and it reads at 14.0 while driving around 40 mph and drops to 12 - 13.5 at idle. I can drive it for miles without any problems but then if I shut it off it may start back up it may not. What's up with that?

Do you guys think that it's the dreadful hot start issue, or something else. I was told that it could be my timing is too far advanced. Can't check it because I have the Taylor braided steal spark plug wires and I haven't found a timing light that will work on them yet. It will start right up if I jump start it. I have purchased a hot start relay from Jegs but I haven't put it on yet.

So is my charging system/alternator working right? I have a one wire 100 amp alternator. I took the battery to Sears and they said that it was fine. Can anyone help me out here. One more thing, this things drinks gas like yoou wouldn't believe. It doens't smell, or produce any type of smoke whatsoever. Thanks guys.
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Old 02-13-2004, 02:52 AM
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Sounds like hot start

Sounds like a hot start problem to me. Are you running headers? I did the F**d solenoid conversion and that eliminated my problems. Hope this helps.

Ron
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Old 02-13-2004, 09:07 AM
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Yes I am running headers. I had thought that the mini starters were supposed to eliminate the hot start problem.
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Old 02-13-2004, 09:58 AM
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I`ve went over this many times myself, after my car ate a total of 8 starters, I decided it was time to do something about it, so I got some 2 gauge wire, added connectors to both ends, ran one end to the frame and the other to the block, and from the block to the battery, then I added a 10 gauge ground from the battery to the fender, then another 10 gauge from the frame to the firewall, and from there I used the factory ground strap from the firewall to the intake, this cured all my hot start problems, and all my electrical woes, my header makes contact with the starter, and I have no heat sheild, it doesn`t matter if the weather is 100 degrees or 20 degree`s, the starter fires the car up the minute I touch the key with no dragging or grinding, it also spins the engine over with ease with plenty of speed. no matter what kind of starter you use without proper grounds it`s good as useless, the downsides to bad grounds are, it wears out starting components and electrical components in half the time, head lights won`t be as bright, gauges will fluctuate, along with many other woes that go along with it, try adding grounds to your system as I did, I`m betting it takes care of the problem.
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  #26 (permalink)  
Old 02-13-2004, 10:30 AM
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Quote:
Originally posted by camaroman7d
Did you build this engine yourself? I agree the oil pressure is low and I would be concerned. In a fresh tight engine it should not be that low.

Does the noise you hear go away if you get the RPM's and oil pressure up (maybe 2000-2500RPM?).

There is a 1/2" plug that goes under the rear main cap on SBC engines, these are often over looked and would cause you to have low oil pressure, this would also cause the noise you hear (because the crank is not getting enough oil). Do yourself a favor and pull the pan and have a look at the bearings. If you catch it early enough you won't have to turn the crank and it will save you time and money. However if you wait you run the risk of chewing up the crank and getting metal through out your engine.

10psi per 1000 RPM is a rule of thumb and I agree with it. The problem is the noise along with the low oil pressure, that tells me something is not right (IMO).
That plug has no effect on oil pressure. It simply directs the oil through the filter. No plug, no oil filtration.

By using the 20w-50 oil, you have put a band-aid on the problem. You most likely have around .003" clearance on the main bearings. Not a problem in itself, but it doesn't lend to a long lived engine.
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