Oil from blow by and breather...need help

takedown95

takedown95

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Aug 18, 2011
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Ok here's what's happening (built 12v):

It's been having oil come out the blow by tube and breathers pretty regularly with no load in the higher rpm range (3k-5k). Oil pressure is at about 70psi at start and idle and will climb to 100+ at higher rpms. Once warm the pressure came back to around 50-60psi at idle. I changed the oil, put on a new filter and had the oil analyzed. I also pulled the injectors and compression tested the cylinders thinking it was a ring issue. Here's what I found:



Cylinder

#1 380psi

#2 360psi and Injector was caked (guessing the gasket was letting compression by)

#3 390psi and injector body was covered in oil (not sure if it was from the cylinder or what came out of the breather and down the head)

#4 350psi

#5 350psi

#6 360psi

These pressures seem normal for a built lower compression engine but the variance has me confused.

Here are oil analysis results (all in ppm readings)
Wear Metals:
Iron-193
Chromium-15
Nickel-2
Aluminum-12
Copper-8
Lead-9
Tin-3
Cadium-0
Silver-0
Vandium-0

Contaminant Metals:
Silicon-43
Sodium-3
Potassium-1

Muilti source:
Molybendium-124

I'm at a loss. I was thinking rings but the compression test came out reasonable? Thoughts?
 
20 hooks on the motor.

Only running for 10-15 minutes. It won't start pushing oil out until I get higher in the rpm band. At about 3k I start to see bubbles out of the breathers. No presure out of the breathers at idle.
 
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Just my 2 cents, but on a lowered compression motor no load you might not have enough boost to clean up the 2 lower compression cylinders. Have you thought about putting in on a dyno so you could test under load?
 
6.4 F-350 said:
Just my 2 cents, but on a lowered compression motor no load you might not have enough boost to clean up the 2 lower compression cylinders. Have you thought about putting in on a dyno so you could test under load?
Click to expand...

I'm not following....can you explain more
 
Well as you are making boost it raises cylinder pressure and makes more heat in order to keep the rings seated and will reduce blow by and the oil slobber. That is depending on what you are running for rings most of them are dished so the more pressure in the cyliner the harder the rings are pushed against the cyliner wall. So if you are reving the engine with no load you might not have enough cylinder pressure to keep the rings seated at higher RPM. Like I said I am no engine builder just my 2 cents.
 
6.4 F-350 said:
Well as you are making boost it raises cylinder pressure and makes more heat in order to keep the rings seated and will reduce blow by and the oil slobber. That is depending on what you are running for rings most of them are dished so the more pressure in the cyliner the harder the rings are pushed against the cyliner wall. So if you are reving the engine with no load you might not have enough cylinder pressure to keep the rings seated at higher RPM. Like I said I am no engine builder just my 2 cents.
Click to expand...

Gotcha...that's what I thought you were getting at. The "to clean up" threw me off and made me think of exhaust smoke. Thanks.

I don't have access to a dyno but I can find another way to load the turbo.
 
takedown95 said:
Ok here's what's happening (built 12v):

It's been having oil come out the blow by tube and breathers pretty regularly with no load in the higher rpm range (3k-5k). Oil pressure is at about 70psi at start and idle and will climb to 100+ at higher rpms. Once warm the pressure came back to around 50-60psi at idle. I changed the oil, put on a new filter and had the oil analyzed. I also pulled the injectors and compression tested the cylinders thinking it was a ring issue. Here's what I found:



Cylinder

#1 380psi

#2 360psi and Injector was caked (guessing the gasket was letting compression by)

#3 390psi and injector body was covered in oil (not sure if it was from the cylinder or what came out of the breather and down the head)

#4 350psi

#5 350psi

#6 360psi

These pressures seem normal for a built lower compression engine but the variance has me confused.

Here are oil analysis results (all in ppm readings)
Wear Metals:
Iron-193
Chromium-15
Nickel-2
Aluminum-12
Copper-8
Lead-9
Tin-3
Cadium-0
Silver-0
Vandium-0

Contaminant Metals:
Silicon-43
Sodium-3
Potassium-1

Muilti source:
Molybendium-124

I'm at a loss. I was thinking rings but the compression test came out reasonable? Thoughts?
Click to expand...

Why is the oil pressure so high.
 
sounds like your bypass in your oil cooler isnt working properly. your oil pressure should only get to like 70 or 80. also have you checked your valve seals they could be allowing oil in too. does your coolant bubble or seem pressurized?

did the company that did your oil sample add any notes to your results as if your too high on some of the products found in your oil? most will tell you if your normal based on mileage or hours on the engine or if your above normal on the contents of the oil.

have you changed your head gasket and used a thicker one? that could explain the lower CR, if not then that might be a little lower than what i would think is normal.
 
There's no oil cooler on the truck, oil pressure come back down to 50-60psi once warmed up.

Copper head gasket

No extra pressure in the radiator or hoses.

Oil analysis showed moderate wear. The recommendation was to watch and trend. The only componants that were abnormal were silicon and Cr. The silicon is likely because of no air filter and I live in a sandy area. Cr made me think rings but could also be because of the abrasion of the sand. The levels of Cr were only mildly abnormal not critical.
 
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is the gasket stock thickness? there is an oil on the side of the block where you put your oil filter. unless you have removed this set up with a remote filter you should still have this. should look something like this. at at the top shows a plug with a spring and plunger under it. this is your bypass which opens and lets oil by the filter when pressure gets too high. just clairifying your set up here to help diagnose since i dont know any info on your build.

oilcooler.jpg
 
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takedown95 said:
There's no oil cooler on the truck, oil pressure come back down to 50-60psi once warmed up.

Copper head gasket

No extra pressure in the radiator or hoses.

Oil analysis showed moderate wear. The recommendation was to watch and trend. The only componants that were abnormal were silicon and Cr. The silicon is likely because of no air filter and I live in a sandy area. Cr made me think rings but could also be because of the abrasion of the sand. The levels of Cr were only mildly abnormal not critical.
Click to expand...

If you're talking 50-60psi at idle thats high IMO.
 
takedown95 said:
There's no oil cooler on the truck, oil pressure come back down to 50-60psi once warmed up.

Copper head gasket

No extra pressure in the radiator or hoses.

Oil analysis showed moderate wear. The recommendation was to watch and trend. The only componants that were abnormal were silicon and Cr. The silicon is likely because of no air filter and I live in a sandy area. Cr made me think rings but could also be because of the abrasion of the sand. The levels of Cr were only mildly abnormal not critical.
Click to expand...

No air filter?!?
 
Chevycummins said:
is the gasket stock thickness? there is an oil on the side of the block where you put your oil filter. unless you have removed this set up with a remote filter you should still have this. should look something like this. at at the top shows a plug with a spring and plunger under it. this is your bypass which opens and lets oil by the filter when pressure gets too high. just clairifying your set up here to help diagnose since i dont know any info on your build.

oilcooler.jpg
Click to expand...

Not sure about the thickness.

There is still the bypass valve on the truck. I can pull it to see if it's caked or plugged? Other suggestions?
 
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