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Well I seam to be having a little blow-by. I'm not sure what is causing this though. I sometimes wont have it and sometime I will. I will have more blowby when I have to get into the truck alot to pass people on the road or such. What could be causing the oil everynow and then? What could case crank case pressure like that? How Could I stop it? I wouldn't think the rings would be worn out at 200k.

Thanks,
James.
 

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i am having the same problem.. can anyone help
 

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Well I seam to be having a little blow-by. I'm not sure what is causing this though. I sometimes wont have it and sometime I will. I will have more blowby when I have to get into the truck alot to pass people on the road or such. What could be causing the oil everynow and then? What could case crank case pressure like that? How Could I stop it? I wouldn't think the rings would be worn out at 200k.

Thanks,
James.
All engines have blowby, new or with 4 million miles on them, then add 30-40lbs of boost and blowby will increase significantly. Make your self a catch-can/ breather bottle and attach it to your draft tube under the truck, at least that will collect the oil and keep it from spraying all over your truck.:thumbsup:
 

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A little blowby is normal. Cummins has parameters for how much is acceptable. You can have it checked at a Cummins shop with a 5.9 manometer fixture or make a basic manometer and do it your self. Illflem has posted how to make one several times. If you install a catch bottle make sure it has enough holes to vent the system. If it pressurizes too much you will blow the seal on the push rod cover (also known as the tappet cover), and you do not want to do that. If your blowby oil loss is excessive, like over a qt every 2000 miles, and the cause is worn rings, you can probably blame your aftermarket air filter.
 

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how can a after market air filter cause blowby? im not questioning you im just curious ive never heard that before
 

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how can a after market air filter cause blowby? im not questioning you im just curious ive never heard that before
Some freeflowing filters allow abrasive particulates to enter the cylinders. They act as sandpaper on the cylinder walls and wear out the rings prematurely and also wear out the valves.
 

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Subscribed - interested in the DIY manometer
 

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If the vacuum pump cannot achieve a vacuum it will become a air pump and push air into crankcase. Higher the RPM the higher the air volume.
 
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