Excessive Crankcase Pressure

[00 Agent]

Hey guys, been fighting with this problem for a while now, can't find answers anywhere.

Guess I'll start from the beginning, I completed a JDM swap in the last few months. I replaced a bunch of stuff while I was at it, including a new oil filter housing from MachV. Anyway, drives great, but when I started opening it up it blew the dipstick and a bunch of oil out. So I thought no biggie, clamped the top of the dipstick tube to keep it in. Now if I get all over it it will blow out the seal on the oil filter (next weakest point I guess). It's really wierd though, sometimes I could get all over it even in high RPM's and it would be fine, yet then when I would just launch hard or something it would blow.

I have replaced the PVC valve with a straight fitting and have that and the crankcase breather both routed to a catch can (per taboo's method), so I know I have plenty of ventalation. I have a mechanical oil pressure gauge and the oil pressure doesn't seem to be building up excessively. Did a compression test and got high 140's across all cylinders. I'm lost.

Yes, I posted on both forums...I need an answer!

 

[Defiant]

Has to be blowby. Is that cam cover vent blocked at all? Have you checked it? Perhaps try a leakdown test.

And don't cross-post.

 

[00 Agent]

Has to be blowby. Is that cam cover vent blocked at all? Have you checked it? Perhaps try a leakdown test.

Blow-by with damn near 150 compression on every cylinder? Yes, I've double checked the valve cover 'vents'.

 

[volljari]

I am getting the same problem I can't figure it out. It was running fine then all of a sudden it started to blow the dipstick out. If you have any answers please let me know so I don't blow anything up...

 

[Maglin]

Bringing this one back out. I to am haveing the same issue. I don't have a leak down tester (yet) but just did a compresson test today. 1 and 2 are at 150, 3 and 6 are at 160 so my compresson is great. With the car at idle a lot of crank pressure is seen though. At high RPM's the crank pressure drops a lot. I haven't messured it but I took the PCV and breather line off and you can really feel the aire rushing out. Bring it above idle and it almost goes away completly. I'm thinking of building a Catch Can this weekend and just running my PCV and breather into it. I hate the vaccume leak I get from that damn PCV valve.

So did either of you guys figure out what was causeing this?? I'm thinking it is still blow by related. Once I get my hands on a leak down tester I can trouble shoot further.

 

[leet]

Do you guys have too much oil in the crankcase?

 

[Maglin]

I know I don't. I don't spray oil much. Happens when I really get on it though. Comes out of the dipstick tube. Even though I have good compression I'm thinking that I have a blown headgasket and am going to replace it this next paycheck and put the ARP Studs in while I'm at it. I'm loosing coolant as well but at a very very slow rate.