'98 S70 Excessive Blow-By?
#1
'98 S70 Excessive Blow-By?
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!
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!
#5
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!!
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!!
#6
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!
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!
#7
#8
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!!
#9
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.
#10
#11
#12
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.
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!!
#13
#14
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?
#15
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.
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.
#16
#18
#19
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.
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