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So, yet another question!!! this truck has new oil in it brand new almost! never even ran engine on the oil. and the engine had no water in it (in the cooling system) so my oil is milky white like it has water in it. I just think its a bad head gasket seal. but heres my main problem i know they dont push a lot of oil pressure and ive never exactly got the engine to run but it has oil in it like i said but even after the hours ive spent cranking it over there seems to be absolutely no oil in the oil filter how is that possible?? does the engine only push oil to it if its warmed up? what can you tell me about this issue because im days from tuning my engine and id hate to seize the engine!!! please help!! again i know nothing about how this oil system works!!! my filter was replaced about 2 years ago doesnt seem like oil has ever touched it?? 

 

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Have you cleaned all the lines in the system? It should run good oil pressure, standard is about 30-45 psi at operating speed/temp, but of course with age you can lose some of that. Have you ever dropped the oil pan to check the sludge, or even pull a tappet cover...these engines were notorious for building sludge, which could mean a plugged oil gallery. You can also pull the oil pump quite easily and check its condition.

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If the engine has not been run since it was rebuilt then the oil pump might need a little priming. Some people pack them with grease when putting things together. In my limited experience, pulling the spark plugs to relieve the compression and then using the starter is enough to get oil pressure in that situation.

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You should have a look at the engine section of a manual. There could be several possiblities.

First things first though. Drain the oil into a clean pan and see if you have any sign of seperation. If water is present then it is a good thing you were not able to get it running.

 

If there is no oil in the filter it could be a couple of things. No prime on the oil pump as mentioned is one. Could be the pressure relief valve is stuck as well.

 

Jeff

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Correct me if I am wrong, but won't the pressure relief valve prevent the filter from filling under these conditions? It is set to open at around 60PSI i think, so no oil should be flowing there. Other than that, was there water in the oil when you first got the truck?

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Oil should pump to the filter almost as soon as it does to any place else.

 

Your head gasket should not be bad unless it was already and was reused 

 

You said  in an earlier post that you had the head off but I don't recall if you said you used a new gasket

 

A broken spring on the oil pressure relief valve if stuck in the open position would allow oil to drain back to the pan, but there should be some indication that oil had flowed through the filter canister

 

 

If stuck in the closed position the canister would fill and remain filled

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Edited by shel_ny

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What about condensation? Especially if the oil has been in an engine for a long time and if the engine is run, it's not run long enough to warm up.

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Only on a lot of quick runs, my understanding is virtually no run time. Definitely a leak in the cooling system somewhere that is contaminating the oil. If the headgasket was crushed once, it shouldn't be used again, and a big issues with these flatheads is a warped head, so even with a new gasket, issues can arise right away

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I have a 1951 377ci  flathead Moly Block six truck engine in a parts truck that I have had for years. I have kept clean oil in it and run it 2 to 3 times a year to keep the core engine good. No oil color probems till one year.

Had a hard time figuring out why all of a sudden the oil turned milky.

No cracked block. Did not pull the head.

I did pull the pan.,. Cleaned it free of oil and sludge...  hours of watching to find coolant/ water leaking from the water pump down to the front of the block to the crank seal and wicking through into the timing gear seal and down into the pan. Took a week of careful watching to find this odd leak.

A re-sealed water pump and crank seal and all is good 5 years later!

Bob

Edited by Dodgeb4ya

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1950,

As in most engines of this general design, the regulator plunger doesn't allow oil to flow to the filter canister until the pressure has come up to about 20 psi (maybe less in the Mopars). The other suggestions are good, especially the possibility of a need to prime the pump, but I though I should mention the designed-in prevention of oil flow to the filter. They do this to prevent loss of pressure at low rpm (that's why cranking speed won't get it there) when a bypass type filter is employed. There is a restrictive orifice in the canister center tube (approx 1/16 in.) to prevent significant pressure loss at higher rpm.  By then the pump is putting out sufficient volume so it's a non-issue.

You may prime it by taking off the end plate (DON'T let the outer-rotor fall out! They may break if it falls to the floor!) and apply some soft grease to the rotor cavities and ends. That should be enough to seal it internally for priming.

F

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Hmmmm.

I had deleted that previous post because of errors in my "facts" but it made it through anyway.
I apologize for the bad info. I tried a number of "edit" attempts but obviously failed. I need to be more careful and learn how to use this forum.

Frank

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