My motor was running at idle (900 RPM or so) and I removed the oil cap. I was met with lots of air rushing out the oil cap hole and a deep rumble. What does this mean? I know I read somewhere that this is a bad thing, I just dont remember exactly what it means. TIA.


[Modified by VTEC-DA, 3:09 PM 3/14/2003]

 

Well, it sounds like you got hella blowby. Which means your piston rings are shot. Do you have blue smoke comming out of your exhaust pipe?

 

I thought it was blowby, I just didnt want to be wrong. No blue smoke, yet. Looks like I am going to have to put all my plans on hold, and replace the pistons and rings.

 

I dont think you need to replace the pistons unless you're going for all motor and want to increase your compression ratio or go turbo and decrease it. If not, dont waste your money.

 

check your PCV ?

 

I am going all motor, and while I am down there, why not replace the pistons too. I was just hoping that I wouldnt have to do that for a while.

 

I thought removing the oil cap w/ engine running would result in oil spouting out and making a mess everywhere.

 

Nope, only a little came out and thats only because so much air was rushing out. Normally, no oil comes out.

 

I would say its normal. Dont sweat it. Its air from the valve movement. Dont open it when the car is running.

This is one reason to use a metal oil cap when racing, that air presure has been known to break open the plastic ones (Realtime Racing)

 

This isnt the little bit of air that normally comes out. This is a TON of air. Enough to blow my hair everywhere when I bent over to look in the hole. And I was like a foot and a half about the hole. This definately isnt normal.

 

Do a compression test, that will tell you if your rings are bad. Start there.

 

what would be average numbers per cylinder? just curious

 

Do a compression test, but chances are it's nothing to worry about.

It will make a mess if you try to add oil while the motor is running, trust me I've seen it first hand. I've never laughed so hard in my entire life.

 

I already compression tested it. It was normal in 3 or the four, but one was pretty low. And I wasnt adding oil, it looked like the oil cap was on crooked, so I took it off to put it on correctly and when I did, whooosh, there was the air.

 

rev it above idle and oil is gonna spray everywhere...

What does it mean when air comes out of the oil cap? It means you're a dumbass and should put you're oil cap back on, then stop playing with you're car when you have no idea what you're doin. Our cars have a PCV system, which means the crankcase and head are under positive pressure to evacuate blowby gasses, which means its normal, so stop crapping you're pants.

And yes i almost did pee myself when I thought about you standing over you're car with you're hair blowing everyhwere going "gee, this CANT be good, durrrr!"



[Modified by Br1t1shguy, 7:57 AM 3/15/2003]

 

integraholic, do you need to take out engine to replace pistons? thinking of getting itr pistons.

 

yes.

 

Talked to a mechanic and he said that it did seem like alot of air coming out (more than normal), and bad piston rings could account for that and the low compression in cyl. 3. Whatever though, I was going to rebuild in a month or two, so I will just do it now. CTR pistons are on there way, and will be going in next week sometime. Its gonna be nice to be able to replace everything and have a "new" block again.


[Modified by VTEC-DA, 11:20 PM 3/15/2003]

 

well you technically you don't HAVE to, but it's about 23643423423x easier if you do.

 

how hard is it to lift your engine out, and by mean lift, I dont mean trying to pull as hard as I can, i mean like unbolting everything and making the engine free to be pulled wiht a lift.