Hello everyone,

About 4 weeks ago, my 1998 S70 (non-turbo) blew the head gasket.
So I took out the head, had it resurfaced, new gaskets, new valve guides and seals, etc etc.

I took that time to install a new water pump, and new timing belt.
I bolted everything back up, and it ran superb.

This weekend, I went to re-torque the head.
So I removed the cam cover, re-torqued, and bolted everything back up.

I was having a problem since 4 weeks ago:
I see too much pressure inside the crankcase.

Whenever I remove the oil fill cap, I can hear when it releases pressure.
This is causing oil to slowly seep out in other places.

So, I was wondering: What else could cause this excessive crankcase pressure?

Could it be the PVC setup (I know there's a tube running from the camshaft cover, to a black plastic box under the intake manifold.

Any idea what I can check/verify?

Thank you!

Very much appreciated!

 

Ahh, yea! Should have done the PCV when the head was done.

Check compression, if good, do the PCV system replacement.

 

 

Those are awesome videos!
Thank you!

I just ordered the parts from RockAuto... hopefully they'll arrive on time for next weekend...

Will update then.
Thanks!!

 

Update!
The parts arrived on Thursday night.
So today early in the morning, I got to replacing them.
I took off the intake manifold.

Removed the PCV breather box and all the tubes going into/outof it.
I replaced all the tubes with the new ones that arrived, and re-used the metal clamps (never opened them).

I also found out that the small vacuum line running from pre-throttle body, to the passenger-side of the intake manifold (small nipple at that end) was broken in half.
So it was loosing vacuum there!

I fixed that... bolted everything up... yet it started raining heavy and I had to stop.
I have left to do the airbox, and the cold air intake tube.

I will update ASAP on how it goes.
I hope the "too much pressure" in the crankcase gets solved with this!!

 

Ok, I finished installing all parts.
Turned the engine on... and did "rspi's latex glove test".

I took off the oil filler cap, placed a glove over it... and it started filling up immediately.
So it isn't that it has a little pressure... it has a lot.
Zero vacuum.

What else could I check?
I can confirm the PCV box and hoses are new... and clear of obstructions.

The only other thing that I can think of is the electronic solenoid-looking device that's attached to the radiator fan's shroud.
Maybe that thing is clogged?

Any idea what I can do?

Thanks everyone!

 

Did you connect the hoses on the breather box the way they came off? Some people get those switched. The hole to the passenger side closet to the motor goes to the top of the motor.

Also, have you done a compression test yet?

 

100% sure I connected them the same way they came off...
Yet... maybe at some point somebody switched them?

All the diagrams I see online are for the Turbo engine... would you have a diagram for the naturally aspirated engine?


==========
The compression test...
I will do it tomorrow.
I hope it comes out good... yet something tells me... I think that's where the problem lies.
Dang...
Will update ASAP!

Thank you!!

 

It's been a month...any update? I have the same issue with my 98 S70 turbo. Bought with a blown head gasket...now that it is back together, I am getting LOTS of blow-by and cylinders 3 & 5 will not fire. It is not the ignition or fuel systems as I have swapped parts and the misfires stick with 3 & 5. I will do a compression and leak-down test tonight and post the results.

 

Do a compression test. If you just did a head gasket, I would double check spark plug order.

Most of the diagrams show them backwards. The box connects the same for the turbo & NA cars.

 

Should not really need a leak down test. Shouldn't have any valve issues unless you didn't have the head checked out.

 

No update.
I haven't hooked-up the pressure gauge to the sparkplug thread.
Yet I am almost positive the rings are busted and blow-by is excessive.

Please post your results!!

 

These motors almost never have piston issues. Usually a burnt valve or bad head gasket. These head gasket issues rarely mix fluids for some strange reason.

 

Wow... very good insight then.
I stand corrected!

Well... what could be the problem I'm having?
The head gasket is new.
The head and all the valves were re-done by a reputable machine shop.
I replaced the PCV system.

Maybe I messed up in the head gasket?

 

Do a quick compression test. It only takes about 15 minutes. The post the numbers.

When I got my head back from a "very reputable shop", they failed to tell me that there were metal shavings in the head. Had I not dropped it on the ground, I may have never know until after I installed it and destroyed something with the metal floating around in the head.

 

I am embarassed to say that I did not check the wires that I removed. They looked great and so I removed them still attached to the distributor cap and re-installed that way. Tonight I re-checked the wires...3 & 5 were switched and now the engine runs great!

 

FYI: I was so pleased with the outcome tonight I decided not to do the tests, but will do them this weekend so I will have baseline numbers to work with.

 

Don't feel too bad about the mistake. I did a distributor cap/rotor replacement on a v8 chevy once, marked the wires and the cap so I could put it all back together correctly and still screwed it up.

 

I read that you checked for obstructions, but did you check the engine block openings carefully? They are difficult to see inside, so use a mirror and light to verify they are not plugged solid...this does happen. You can also connect a length of hose to each opening and blow into the hose. There should be NO resistence. If there is any, it needs to be opened up.