Sounds like its time for a rebuild..WW
5.7 TPI situation...
Thread Starter
Instructor
Joined: Jun 2010
Posts: 116
Likes: 2
From: Webster Florida
5.7 TPI situation...
Okay so I just bought this 1986 vette.... the PO had in his ad that there is an oil leak... he thought it was the front seal. I'm not sure I agree...
The passenger side rear manifold is where the leak appears to be coming from. Smokes soon after starting.
Looking around the front seal area there is some oil but not that much. I've got a LT1 in my 94 Firebird that I am replacing the front seal on today and it is the front seal. It leaks about a quart every tank of gas.
The vette has a set of after market valve covers are on it. It has cast iron heads. When I got it the oil filler on the passenger side valve cover kept blowing off... so I added another PCV valve to the passenger side to stop this... also removed the valve cover and checked the torque on the head bolts and replaced that gasket.
It still leaks there but now the PVC valve on the drivers side valve cover blows off.
Neither of these blow off when sitting still and reving the engine, they come off while driving.
The oil leak appears more to be coming from the head than from the valve cover...
Any thought on this? Why are the valve covers blowing stuff off them? what could be causing this pressure in the engine? Could the head gasket be bad and causing the oil leak? I've never seen one leak oil.
thanks in advance,
Robert
The passenger side rear manifold is where the leak appears to be coming from. Smokes soon after starting.
Looking around the front seal area there is some oil but not that much. I've got a LT1 in my 94 Firebird that I am replacing the front seal on today and it is the front seal. It leaks about a quart every tank of gas.
The vette has a set of after market valve covers are on it. It has cast iron heads. When I got it the oil filler on the passenger side valve cover kept blowing off... so I added another PCV valve to the passenger side to stop this... also removed the valve cover and checked the torque on the head bolts and replaced that gasket.
It still leaks there but now the PVC valve on the drivers side valve cover blows off.
Neither of these blow off when sitting still and reving the engine, they come off while driving.
The oil leak appears more to be coming from the head than from the valve cover...
Any thought on this? Why are the valve covers blowing stuff off them? what could be causing this pressure in the engine? Could the head gasket be bad and causing the oil leak? I've never seen one leak oil.
thanks in advance,
Robert
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Team Owner
Joined: Jan 2003
Posts: 20,315
Likes: 245
From: Summerland B.C. Canada
Please explain what you did, did you replace the original fitting with a PCV valve ?
From the factory, the driver side PCV valve gets vacuum from the intake base. Is there vacuum on that line from base to valve ?
On the passenger side, fresh clean metered air, is drawn from throttle body into the fitting in the passenger side cover. If you were to have replaced that fitting with a PCV valve, no fresh air would be able to replace those crappy crank case gases.
From the factory, the driver side PCV valve gets vacuum from the intake base. Is there vacuum on that line from base to valve ?
On the passenger side, fresh clean metered air, is drawn from throttle body into the fitting in the passenger side cover. If you were to have replaced that fitting with a PCV valve, no fresh air would be able to replace those crappy crank case gases.
Thread Starter
Instructor
Joined: Jun 2010
Posts: 116
Likes: 2
From: Webster Florida
Please explain what you did, did you replace the original fitting with a PCV valve ?
From the factory, the driver side PCV valve gets vacuum from the intake base. Is there vacuum on that line from base to valve ?
On the passenger side, fresh clean metered air, is drawn from throttle body into the fitting in the passenger side cover. If you were to have replaced that fitting with a PCV valve, no fresh air would be able to replace those crappy crank case gases.
From the factory, the driver side PCV valve gets vacuum from the intake base. Is there vacuum on that line from base to valve ?
On the passenger side, fresh clean metered air, is drawn from throttle body into the fitting in the passenger side cover. If you were to have replaced that fitting with a PCV valve, no fresh air would be able to replace those crappy crank case gases.
I used a PCV valve because it fit.... but it is coming off the TPI unit. I basically copied how my 305 tpi is except I used the PCV valc=ve at the valve cover.
Team Owner
Joined: Jan 2003
Posts: 20,315
Likes: 245
From: Summerland B.C. Canada
It would be a good idea to remove it.
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