J30 Oil Pressure Building-up

[matt169]

I have a 95 J30 with 267,000 much enjoyed miles. I have been very lucky with this car to have no major repairs. transmission shifts great and engine runs great. About a month ago I noticed smoke from under the hood and found the oil dip stick pushed up and oil had come out from the dip stick. After getting some help on this forum I changed the PCV valves today. They were completely clogged up. I drove around today some and am still having the same issue. While the car is ideling I can remove the oil dip stick and hear lots of pressure release. It only takes a couple of seconds running to biuld up enough pressure where you can here air rushing out. I have since bought an 01 QX4 so I am not without a ride but really want to get this running again as it is in supprisingly good shape for 267K miles. I don't plan on driving it anymore till it is fixed as I fear the gaskets/seals will get wasted (may already be) with the pressure building up. What else should I go after that could be allowing pressure to build up?

[Q45tech]

Worn or/and collapsed Rings/cylinders!

[PalmerWMD]

Worn or/and collapsed Rings/cylinders!

I hope your not right Dennis...

Fred..

[maxnix]

I hope your not right Dennis...Fred..

I hope it's not Dennis' left, either. I do think Q45tech is correct in diagnosing the rise in pressure in the crankcase while operating as failed rings.

A not unexpected problem with 267K miles on an engine with a clogged pcv valve.

[matt169]

I hope it's not Dennis' left, either. I do think Q45tech is correct in diagnosing the rise in pressure in the crankcase while operating as failed rings.

A not unexpected problem with 267K miles on an engine with a clogged pcv valve.

Is $350 from the local junk yard my best option?

[PalmerWMD]

Is $350 from the local junk yard my best option?

Luckily these engines dont seem to cost as much, as Q45 engines.

Fred..:fruit

[elwesso]

Well..... id say after 267k it doesnt really owe you anything..... Especailly since you say its been basically trouble free.....

Id keep driving it until it dies for good, and then see about a used engine..... Maybe for extra measure make a hole somewhere so the pressure can escape.... (may or not be a good idea, id like to get some extra input) They are probably gonna be real cheap since they are the same engine as the 300zx..... Keep your eye out on ebay for japanese take out engines......

[VimyJ]

Wow! 267k miles. Same transmission? Fantastic! What type of lubricants/fluids were you using?

Denis, have you seen worn rings on a VG30DE before?

[maxnix]

Is $350 from the local junk yard my best option?

I would think that rebuilding a VG30DE would not be a daunting task for an independent familiar with Z32 overhauls. Thid might be an atractive option if the rest of the car is pristine.

Look for a race engine preparer. Where are you located?__________________Brian1995 Q45 & Q45t & 2000 Q45

Discover the power of the button!

[Eswift]

276 is amazing, especially with a solid trans still.

i have only heard great things about Z1 motorsports...if i was within 300 miles of there, it would be my first choice.

[Q45tech]

To change the rings you have to pull the engine and remove the heads...........as a used engine is less expensive say $1,200 plus, $900 in R&R parts, and $1800 in labor............under $4,000.

About what we charge to do a ES300/M30.