Greaser67

On a recent long trip while driving at sustained speeds of 70-80 mph both crank seals started leaking. When I remove the oil fill cap it will slightly float on the opening it screws into.

My first thought was a bad cylinder leaking by so I did a compression test. All cylinders were 195-205 psi. The air coming out of the oil fill opening is a very fast pulsing, like every time a cylinder fires it seems like.

Next I thought maybe this was normal and the PCV valve was bad but the plenum is drawing plenty of air thru it when removed from valve cover.

Next with it running I pulled 1 plug wire at a time to see if the pulsing stopped. Pulsing did not stop and engine had a noticeable miss when each plug wire was removed.

The motor runs smooth, has good power and no check engine lite. Oil looks good. Is there anything else that is plumbed into the crankcase that could be causing the positive pressure? Possibly the EGR tied into the crankcase some how?

Anyone have any ideas?

holmesnmanny

blowby is a normal function of even a new engine ... you're fine

slowcivic2k

First off, you fail to identify your vehicle and engine. More info = more results, I suggest you do some homework.

As a cylinder piston moves both up and down, you will have pressure pulses in both the crankcase and cylinders. One pulse in the crankcase, one in the cylinder itself + leakage. This can happen 4, 6 or 1,000 times, depending on what engine you have.

Crank seals leak for a lot of reasons, of which you list no history or other information. Given what you have said, replace the seals and pray.

Greaser67

Car is a 96 with a 2.2 non-Vtec, 100,000 miles.

I realize that blow by is normal, I don't think this is normal though. I have NEVER had an engine that makes more blow by than what the PCV system can handle, the oil fill cap will float on the air coming out of its hole.

The car has not always had air blowing from the oil fill cap will running, I have had the cap off in the past while it was running and I am sure I would have noticed this.

I have spent quite a bit of time searching this site for posts that deal with excessive pressure in the crank case and have came up with nothing, as well as the web. I think I did enough time doing my homework, so I thought I would ask for help. Sorry I forgot to give more info regarding the model and engine of car, some people make mistakes.

The more I think about this post the more disgusted I get. I know I am a very new member to this site and I have not set up my profile yet. So here you go,

47 years old
Owned and repaired everything from model airplanes to diesel tractors.
Work full time as a factory mechanic repairing electric carts to 200 ton brake presses
Work part time a competition engine shop, go karts to pulling trucks.
Have only paid someone once in the last 30 years to repair something for me and I still had to redo it.

I see this site is no different from a lot of the other forum groups out there. A hand full of members who post continuously think they are all knowing and everyone else has to have everything explained to them.

Keep your advise to your self almighty, I will figure it myself.

Administrator please delete my account.

holmesnmanny

You can always conpression test to see the health of the engine.

kidwagon

Strange behavior with such good compression numbers. Possible bad head gasket leak forcing partial compression up through oil drain back holes in the head.