Aftermarket Valve Covers - Missing a PVC Hole?
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Aftermarket Valve Covers - Missing a PVC Hole?
My '85 Fiero came with aftermarket valve covers from Edelbrock and I have a feeling that they are causing an issue and I'd like your opinion on this issue.
The valve cover closest to the firewall has one hole in it for the PCV system in the normal spot on the fiero.
The valve cover closest to the trunk only has one hole in it for the oil fill cap.
I think my engine has a little blow by so I have ditched the PCV valve with a recirculating catch can instead. But it is only hooked up to the one valve cover.
I replaced both valve cover gaskets last night and this morning I started it up and it was doing great. Later I went for a drive and when I came back and opened the hood I found that both valve covers had begun leaking oil again...
Could this be caused by the fact that only one of my two valve covers is venting crankcase pressure?
I'm considering using a hole saw to make my own PCV system hole in the cover that has the oil fill cap on it and making sure both sides are venting.
The valve cover closest to the firewall has one hole in it for the PCV system in the normal spot on the fiero.
The valve cover closest to the trunk only has one hole in it for the oil fill cap.
I think my engine has a little blow by so I have ditched the PCV valve with a recirculating catch can instead. But it is only hooked up to the one valve cover.
I replaced both valve cover gaskets last night and this morning I started it up and it was doing great. Later I went for a drive and when I came back and opened the hood I found that both valve covers had begun leaking oil again...
Could this be caused by the fact that only one of my two valve covers is venting crankcase pressure?
I'm considering using a hole saw to make my own PCV system hole in the cover that has the oil fill cap on it and making sure both sides are venting.
- Shaun41178(2)
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Here's a little story that I think will help.
When I assembled the top end of my engine last time (to fix a leak at the LIM) I used new Fel Pro rubber gaskets for the valve covers.
At the same time I was using a hollow tube to bypass the PCV valve in to my catch can setup.
The cover nearest the trunk began to develop a small leak, but it was big enough that I wanted to fix it so I tore it all apart last night and replaced the gaskets with cork gaskets. When I tightened the valve covers down I used a torque wrench and followed my Haynes manual with torque specs.
At the same time that I replaced the gaskets I also installed a new PCV valve because it fit better than my hollow tube bypass method. The new valve still went to the catch can.
This time around both valve covers began to leak profusely and I can't even hardly drive it because so much oil is being pushed out.
So what is the culprit? Cork gaskets suck? Is the PCV valve not letting enough pressure out and it blew out the gaskets?
IDK. I'm going to try and do a leakdown & compression tests next week to see what the condition of my engine is.
When I assembled the top end of my engine last time (to fix a leak at the LIM) I used new Fel Pro rubber gaskets for the valve covers.
At the same time I was using a hollow tube to bypass the PCV valve in to my catch can setup.
The cover nearest the trunk began to develop a small leak, but it was big enough that I wanted to fix it so I tore it all apart last night and replaced the gaskets with cork gaskets. When I tightened the valve covers down I used a torque wrench and followed my Haynes manual with torque specs.
At the same time that I replaced the gaskets I also installed a new PCV valve because it fit better than my hollow tube bypass method. The new valve still went to the catch can.
This time around both valve covers began to leak profusely and I can't even hardly drive it because so much oil is being pushed out.
So what is the culprit? Cork gaskets suck? Is the PCV valve not letting enough pressure out and it blew out the gaskets?
IDK. I'm going to try and do a leakdown & compression tests next week to see what the condition of my engine is.
Having the breather line only hooked up to one valve cover will not cause any problems, the 3.4l DOHC had it setup this way from the factory in 96-97 (And mine is setup this way).
However, this should be a breather line, not your PCV. The PCV should come from the crankcase somewhere near the intake manifolds, not from the valve covers.
However, this should be a breather line, not your PCV. The PCV should come from the crankcase somewhere near the intake manifolds, not from the valve covers.
88GT 3.4 DOHC Turbo
Gooch wrote:Way to go douche. You are like a one-man, fiero-destroying machine.
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They are nice, but this situation kinda stinks.lucky80 wrote:I've been drooling over those edelbrock VC's myself. But if this is what I'm in for......
Seems to me a simple test to determine if its a pressure or sealing issue at the gasket would be to just run the car without the oil cap and the pcv.
When they vent there are minimal problems. The problem came back (leaky valve covers) when I switched back to a functioning PCV valve.
I believe my main issue is too much blowby creating too much pressure and because of a bottleneck effect in the stock PCV valve system it went to the next weakest link which was the new valve cover gaskets and blew them out.
Fixing it all tomorrow.
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The engine supposedly had around 60K on it when I bought it (more than the car...) but I know that both previous owners drove it hard a lot. Lots of racing and general hot rodding. ...I do to...
I'd love to pull it all apart and rebuild it with the intent of running nitrous and fix the little issues with it.
I'd love to pull it all apart and rebuild it with the intent of running nitrous and fix the little issues with it.
Well what if you had it setup correctly, would it work right then?
There should not be a PCV valve on any of the hoses to your valve covers. The hose from your valve cover should go directly to the air intake, before the throttle body. This system is the breather, not PCV.
The PCV valve should be in the line that goes from your crankcase vent to your intake, after the throttle body.
There should not be a PCV valve on any of the hoses to your valve covers. The hose from your valve cover should go directly to the air intake, before the throttle body. This system is the breather, not PCV.
The PCV valve should be in the line that goes from your crankcase vent to your intake, after the throttle body.
88GT 3.4 DOHC Turbo
Gooch wrote:Way to go douche. You are like a one-man, fiero-destroying machine.
- Series8217
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I don't think the 2.8 has a crankcase vent. You have to use one of the valve covers. The PCV valve goes into one valve cover, and the breather line onto the other.Aaron wrote:Well what if you had it setup correctly, would it work right then?
There should not be a PCV valve on any of the hoses to your valve covers. The hose from your valve cover should go directly to the air intake, before the throttle body. This system is the breather, not PCV.
The PCV valve should be in the line that goes from your crankcase vent to your intake, after the throttle body.
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