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Engine crankcase ventilation

Hello Jose,
As these engines get more miles on them they do suffer more blowby past pistons and valve guides. Usually this is taken care of by the breather at the back of the block. If it becomes plugged, or closed off, in any way, it is possible to blow out the cam cover gasket. There are several solutions. A front breather can be added by using the GTA style oil filler cap, or a later style cam cover can be used that features the upper right corner breather. It may be that the cam cover gasket is tired and just needs replacement. If so it should be sealed to the cover, not the head, with an available gasket sealer, (I use RTV blue for ease of future replacement) and the head surface needs to be perfectly oil free. Excessive tightening of the cam cover hold down bolts can result in a warped cover (leaky) or a cracked cover. If, with a new gasket properly installed, and good crankcase ventalation, the problem still exists, it may be time for engine work or at least a diagnosis of where all that pressure is coming from.

:DGordon Raymond
 

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This is a guess, Jose, but three things happen to the fillers over time. First, the fingers at the bottom lip become bent downward so the cap is never tight when it stops turning. Second, the rubber seal in the top hardens, falls out, or cracks with age. And third, the brass disc above the rubber seal loses its ability to press the rubber down, due to rubber shrinkage, or the disc being dented or bent. A new oil cap is the easy fix though tired ones can be rebuilt easily enough. Don't forget, you will still probably have to replace the cam cover gasket. With 1600 engines without the two small bolts through the front of the cam cover and head, the gaskets often leak at the front, causing the appearance of a leak from the filler. Gordon Raymond
 
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The correct washers are four or five fiber with one or two aluminum. The aluminum are usually in the middle. The purpose is electrical. It was found the fiber washers could electrically insulate the cam cover from the rest of the engine, and with sufficient gasoline vapor in the blow by under the cover, if a plug wire shorted to the cam cover, cause an internal explosion inside the engine. Not good.
Your leak is likely the half moon rubber seals at the back. They do dry out and shrink with heat and age. Did you check the cover gasket surface to be sure it is flat? The covers can get warped, though they usually crack, if too much torque is used on the cover hold down bolts.
Gordon Raymond
 
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