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kennyg1966
04-13-2022, 02:31 PM
Thinking about purchasing a 1990 ZR1 with 84000 KM(canada)
a mechanics diagnosis is:
Oil leaking from intake manifold, oil cooler lines leaking, oil pan gasket leaking could be the Oil Pressure Regulating Valve Cover Plate. Are these expensive to fix. I can get the car for around 20k Canadian(16k usd) I intend to do the simple things myself. I have changed engines myself, just have to get accustomed to the LT5.
thanks in advance

A26B
04-13-2022, 06:41 PM
Thinking about purchasing a 1990 ZR1 with 84000 KM(canada)
a mechanics diagnosis is:
Oil leaking from intake manifold, oil cooler lines leaking, oil pan gasket leaking could be the Oil Pressure Regulating Valve Cover Plate. Are these expensive to fix. I can get the car for around 20k Canadian(16k usd) I intend to do the simple things myself. I have changed engines myself, just have to get accustomed to the LT5.
thanks in advance

Here is a link to only the Gaskets & Seals category of Jerrys Gaskets.
https://www.jerrysgaskets.com/gaskets-seals/

1991 Corvette ZR-1
04-15-2022, 12:13 AM
Thinking about purchasing a 1990 ZR1 with 84000 KM(canada)
a mechanics diagnosis is:
Oil leaking from intake manifold, oil cooler lines leaking, oil pan gasket leaking could be the Oil Pressure Regulating Valve Cover Plate. Are these expensive to fix. I can get the car for around 20k Canadian(16k usd) I intend to do the simple things myself. I have changed engines myself, just have to get accustomed to the LT5.
thanks in advance

The oil leaking from the intake manifold could actually be the pvc grommets allowing oil past and it?s collecting in the recesses between the injector housings and heads. Oil pressure regulator plate access cannot be done well unless you remove the remote oil filter housing and other items in the area. You are going to need room to work because when removing the old cover gasket, some will inevitably stick and need to be scraped off.

I believe there is a method for removing the motor mount nuts from underneath the frame and raising the engine up marginally, but this is if you want to just tighten the two 8mm bolts. When I had my rack and pinion out for rebuild, I had room to snake my hand in there and tighten the bolts. It did not help but your case may be different. Given how tucked in there it is, if you are going to go as far as replacing the lines and you can fully verify the plate is leaking, go the extra yard and remove all necessary to properly access the plate for service.

tccrab
04-17-2022, 04:36 AM
Except for oil blowback via the PCV system, there's no way oil can leak from the intake plenum. Coolant yes, but not oil.
If there's an oil leak under the plenum, there is a weep hole in the back of the block under the starter where the oil will drip out under the car.
It's very common for the oil pan bolts to loosen over time and cause a leak. It's possible to tighten all the bolts with a small ratchet and combinations of wobbly sockets and extensions. The K support frames can be removed to allow easier access to the oil pan bolts.
The oil cooler lines are another common failure, Jerry's Gaskets has the appropriate replacement lines.

Crabs