Oil pressure
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Oil pressure
I put a 87 model 5.0 roller motor in my 68 F-100. I used a HEI style distributor I bought off e-bay. Running an Edelbrock carb. At first everything was great, oil pressure at first start was 80 pounds, once it warmed up it was 60 pounds, stayed about 45 pounds idling. Now about a 1000 miles later it cranks at about 50 pounds cold, goes to about 25 or 30 pounds hot and idles at nearly zero. Couple of guys have told me its the gear worn out on the dist. causing it, that it's not compatible with the roller cam. Anyone ever heard of this?
Tuned
Joined: Dec 2004
Posts: 340
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From: Rock Hill, SC
If the engine is running the distributor gear should be fine. The oil pump runs off a hex shaft in the bottom of the distributor shaft. I have seen these round off and slip turning the pump.
Several other things I have seen cause a sudden pressure drop are the check valve and spring in the pump blowing due to high pressure(usually because bearing clearances are to tight), a mechanical fuel pump putting gas in the crank case thinning the oil and spun cam bearings.
Several other things I have seen cause a sudden pressure drop are the check valve and spring in the pump blowing due to high pressure(usually because bearing clearances are to tight), a mechanical fuel pump putting gas in the crank case thinning the oil and spun cam bearings.
Lead Driver
Joined: Aug 2003
Posts: 7,592
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From: **** hole San Jose ca.
2x with Kenny.
I'd trust a manual gauge over an electric one.
I run both type gauges with the manual mounted on the block, if the dash electric one starts getting screwy.. I can check the manual one.
Orich
I'd trust a manual gauge over an electric one.
I run both type gauges with the manual mounted on the block, if the dash electric one starts getting screwy.. I can check the manual one.
Orich
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It's full, in fact I just changed it.
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If the engine is running the distributor gear should be fine. The oil pump runs off a hex shaft in the bottom of the distributor shaft. I have seen these round off and slip turning the pump.
Several other things I have seen cause a sudden pressure drop are the check valve and spring in the pump blowing due to high pressure(usually because bearing clearances are to tight), a mechanical fuel pump putting gas in the crank case thinning the oil and spun cam bearings.
Several other things I have seen cause a sudden pressure drop are the check valve and spring in the pump blowing due to high pressure(usually because bearing clearances are to tight), a mechanical fuel pump putting gas in the crank case thinning the oil and spun cam bearings.
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It's manual. Thank you for your service!!!
Cargo Master
Joined: Oct 2011
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From: Kenner,La.
Oil pressure
I would still check the pressure with another gauge. If it reads the same you could have some plastic from the camshaft timing sprocket that is in the oil pump relief valve. Old rule of thumb, 10 lbs for every 1000 rpm is safe.
Yes I would serve again, I must say that was the longest 4 years of my life.
Yes I would serve again, I must say that was the longest 4 years of my life.
Lead Driver
Joined: Jul 2011
Posts: 8,679
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From: On the Edge of the Desert
Originally Posted by mikeycars
I'm wondering if maybe it's not a bad check valve because at first it was 80 pounds and better. I've never had a small block Ford run that much pressure. Is that normal you think?
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I would still check the pressure with another gauge. If it reads the same you could have some plastic from the camshaft timing sprocket that is in the oil pump relief valve. Old rule of thumb, 10 lbs for every 1000 rpm is safe.
Yes I would serve again, I must say that was the longest 4 years of my life.
Yes I would serve again, I must say that was the longest 4 years of my life.
Fleet Mechanic
Joined: May 2001
Posts: 1,396
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From: Cupertino
Your gauge is screwball. SBFs do not carry anywhere near 80 psi.
I suggest buying a cheapo screw-in mechanical gauge and checking oil pressure at the block.
If the readings are anywhere near truth, you will destroy that motor.
If you are driving it, listen for the rattle of collapsing lifters. If you hear that, park and tow.
Small blocks will hold oil pressure with one quart in the crankcase. They are happy as long as the pump gears can bite oil.
Semper Fi
I suggest buying a cheapo screw-in mechanical gauge and checking oil pressure at the block.
If the readings are anywhere near truth, you will destroy that motor.
If you are driving it, listen for the rattle of collapsing lifters. If you hear that, park and tow.
Small blocks will hold oil pressure with one quart in the crankcase. They are happy as long as the pump gears can bite oil.
Semper Fi