Ernie ingling
Well-Known Member
Appears block heads not cleaned after machining any grit in oil pan along with bearing material?
383 Low oil pressure,
- Thread starter __Larsson____
- Start date
GreatLakesMopar
Member
As someone stated..This issue was BUILT INTO THE ENGINE. ON A REBUILD.
1. MOTOR OIL VISCOSITY. NOT ISSUE IV RAN 20 50 CASTROL GT FOR YEARS IN MY 383. .
2. POSSILBE. MAIN BEARING. MISMATCH
3. OIL,PUMP ASSEMBLY AND BOLTS LIKE STATED EARLIER.
4. OIL. PICKUP. In the oil pan
Was it replaced ? With the correct one.?
Personally I'm thinking.
The pickup. Is not. TIGHT.
5. CAM BEARING FAILURE.
HEY. DOES THIS ENGINE START TO RATTLE THE ROCKERS. WHEN YOU LOOSES PRESS?
1. MOTOR OIL VISCOSITY. NOT ISSUE IV RAN 20 50 CASTROL GT FOR YEARS IN MY 383. .
2. POSSILBE. MAIN BEARING. MISMATCH
3. OIL,PUMP ASSEMBLY AND BOLTS LIKE STATED EARLIER.
4. OIL. PICKUP. In the oil pan
Was it replaced ? With the correct one.?
Personally I'm thinking.
The pickup. Is not. TIGHT.
5. CAM BEARING FAILURE.
HEY. DOES THIS ENGINE START TO RATTLE THE ROCKERS. WHEN YOU LOOSES PRESS?
andysuperbee
Member
andysuperbee
Member
if there isn’t many miles on the engine change the oil pump but, put a Melling pump on it.
Andy
stock Chrysler pumps sometimes have pressure problems.
Andy
stock Chrysler pumps sometimes have pressure problems.
GreatLakesMopar
Member
LET'S GO BACK TO ENGING BEARINGS. .
THESE ENGINE'S CAME IN,A VARIETY OF FLAVORS INSIDE THREWOUT THE YEARS.
I'D RECOMMEND YOU CHECK THE BUILD CODES STAMPED ON THE BLOCK .DECODE IT AND MATCH THAT TO THE BEARINGS. UNC. INSTALLED.
JUST A THOUGHT. STAY SAFE ALL STAY WELL. AND God Bless Us All
THESE ENGINE'S CAME IN,A VARIETY OF FLAVORS INSIDE THREWOUT THE YEARS.
I'D RECOMMEND YOU CHECK THE BUILD CODES STAMPED ON THE BLOCK .DECODE IT AND MATCH THAT TO THE BEARINGS. UNC. INSTALLED.
JUST A THOUGHT. STAY SAFE ALL STAY WELL. AND God Bless Us All
Save your time and money on an oil pump change. Oil pressure is determined by rod and main bearing clearance, not the oil pump!
Judging by the bearings condition the crank will need turning/replacement.
Danny Tuel
Well-Known Member
I can't believe you did a rebuild and didn't replace cam and cam bearings, lifters and oil pump? If your gonna do it why go half the way and as you are finding out doesn't save money in the long run.
MoparDanMan
Well-Known Member
Could use some more information. How many miles on the engine? What is the oil pressure cold?, and at temp? Most of the time I have found it to be worn cam bearings. Running a heavier oil, say 20W50 will help for a while.
MoparDanMan
Well-Known Member
Mains usually don't have much to do with oil pressure
joemish
Well-Known Member
with your train of thought might as well change the motor while your at it. Just change the oil and filter
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He had already stated that the engine wasn’t cleaned out and there was metal filings everywhere. Kim
__Larsson____
Well-Known Member
They were all good! The thing is that there was gas in the oil who wrecked the motor.
When I rebuilt mine I installed a used cam and lifters. Mine has run perfect for 22 years. So I'll disagree with that statement.
Dave Eamon
Member
Why would you take it apart if it ran well? If it ain't broke, don't fix it. You can't get proper parts anymore, so leave it alone!
My '75 Road Runner is under restoration. I completely disassembled it. The body work and paint are done. The interior is done. Both are gorgeous! The 400 4 Barrel runs just fine, so I will leave it alone! I have replaced the valve cover gaskets and the pan gaskets, but nothing more. I am replacing the external accessories and repainting it, but that's it! It will continue to run just fine for many years to come.
The TorqueFlite 727 also works fine, so I will leave it alone. I have replaced some external seals that were weeping and the pan gasket, but nothing more. It worked fine when it came out of the car and it will continue to work fine for years after it goes back in.
Modification? Why bother? What, will that get you to the show faster? Would that make your car incorrect or non-numbers matching? Yes? Then why do it? That shatters resale value!
Bottom line: again, if it ain't broke, don't fix it. Of all of my car guy buddies, those who have no troubles are those who left it alone! Drive your car, maintain it, enjoy it and leave it alone. If you will just maintain it and leave it alone, it will serve you well for many years!
Dave
My '75 Road Runner is under restoration. I completely disassembled it. The body work and paint are done. The interior is done. Both are gorgeous! The 400 4 Barrel runs just fine, so I will leave it alone! I have replaced the valve cover gaskets and the pan gaskets, but nothing more. I am replacing the external accessories and repainting it, but that's it! It will continue to run just fine for many years to come.
The TorqueFlite 727 also works fine, so I will leave it alone. I have replaced some external seals that were weeping and the pan gasket, but nothing more. It worked fine when it came out of the car and it will continue to work fine for years after it goes back in.
Modification? Why bother? What, will that get you to the show faster? Would that make your car incorrect or non-numbers matching? Yes? Then why do it? That shatters resale value!
Bottom line: again, if it ain't broke, don't fix it. Of all of my car guy buddies, those who have no troubles are those who left it alone! Drive your car, maintain it, enjoy it and leave it alone. If you will just maintain it and leave it alone, it will serve you well for many years!
Dave
myk r sanchez
Well-Known Member
Seriously, the nerve of people modifying their cars. How dare they...
Pretty sure he was being sarcastic.
I don't see how this is helpful.
He has a problem and you aren't offering any suggestions, just a poke in the eye.
Beside the claim that you can't rebuild a motor and expect reliability is simply false.
Plenty of people on this site have done it. Some multiple times.
All the cars we are taking about are around 50 years old, they wear with cold starts.
I was surprised when I took my 66 383 apart. The motor had about 93,000 miles on it and ran well.
A couple of the cooling jacket ports were scaled over with rust scale and flushing the engine was not going to fix that.
By brother took the heads a few years later and they were warped, still ran good.
The machinist who did the engine short block told me he reworked 3 of the rods.
The motor had about 93,000 miles on it and ran well.
I'm hoping __Larsonn__ can get his engine repaired the way he wants it to be.
Stick with it and don't listen to the nay-sayers.
Did you read post #70? Let me share another scenario. When my racecar engine was 1st built the short block was used. The bearings were new. Mains were .0037-.0038" rods (BME aluminum) were .004". Oil pressure was only around 40psi going thru the lights. Pump had the adjustable relief spring full tight. After a few passes it was pulled down and .001" bearings installed to tighten up to .0027"-.0028"M /.003"R. What did that do for pressure? Absolutely nothing. Eventually tracked it down to pushrod feed being too large. Restricted them and after turning the adjuster screw full loose in the pump pressure was still to high. Ended up cutting the relief spring a 1/2 coil 3 separate times. The pressure is now 70psi@7000. Plenty of spots for oil to leak internally in a engine causing lower presure. But bearing clearance seldom bothers pressure anywhere but at idle. Idle pressure means nothing. Pressure is no more than a measure of resistance to flow. Flow is what is important.
Doug
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