How long until an oil leak appears????

[OUbesto]

I just installed new FelPro #1635 silicone valve cover gaskets. I called the FelPro Customer service rep and asked about installation suggestions etc. He said do not use any type of adhesive, sealant etc....just put 'em in bareback! So that's what I did! After reading many of the forum posts, I only tightened the bolts using a nut driver with not much more than a wrist turn snug. Once done, I started engine and let run for about fifteen minutes and could not see any leaks....VOILA!

But my question is how long do I have to wait to truly know if these pretty expensive silicone gaskets are not going to leak? Do you know right away? Is it something that might take a few hours of running time etc??? Any comments?

[Coley]

Small block chevy?......probably 15 minutes, lol.

Great little engines but known as oil leakers

All Good
Coley

[Stocker]

Regardless of how good the gaskets are, I would help them do their job with a set of spreader bars. https://www.amazon.com/s/?ie=UTF8&ke...l_5nrfifmdd3_e

[weq92f]

Probably the last set of rocker cover gaskets you buy for that motor!

-klb

[72LB]

Originally Posted by Stocker

Regardless of how good the gaskets are, I would help them do their job with a set of spreader bars. https://www.amazon.com/s/?ie=UTF8&ke...l_5nrfifmdd3_e

I agree if your using steel covers.

[cleszkie]

Are these the steel reinforced blue silicon gaskets. If so, I have had very good results with these. But I also ditched the stamped steel rocker covers in favor of some cast aluminum units.

You will need to run longer than 15 minutes at idle. Go out on the freeway and then come back and shine a light up at the back outside corner of each rocker cover. if you see any wetness on the head, you have not completely stopped the leak.

['70_402]

it has to do more with the type and quality of your valve covers than anything... you can use an old cheap cork gasket with some nice thick alum covers with a good flange and you'll be fine for years!!

[OUbesto]

I did install The FelPro blue, steel reinforced gaskets. They did install quite easily largely because of their rigid structure. I could easily use my fingers to hold in place then position valve cover over the head. I then lined up the holes and used a punch to center up the cover, the gasket over the bolt hole. Very easy! The worst part of the job was cleaning off the old RTV and glued on cork from the valve cover.

[OUbesto]

Originally Posted by Stocker

Regardless of how good the gaskets are, I would help them do their job with a set of spreader bars. https://www.amazon.com/s/?ie=UTF8&ke...l_5nrfifmdd3_e

Thanks for the suggestion on the spreaders. I bought them today from Amazon although I had to find the 8 cyl BB set.

[BRL]

Originally Posted by '70_402

it has to do more with the type and quality of your valve covers than anything... you can use an old cheap cork gasket with some nice thick alum covers with a good flange and you'll be fine for years!!

...yep, I put quality FelPro under my Bug valve covers without lock washers...and lost one cover on a steep hill in the middle of the night, in the middle of nowhere!

Drilled holes in the Bug valve cover bolts and safety wired them.

I think I have cork gaskets under my aluminum covers on the Chevy...well they don't leak anymore than anything else does under that hood! HA!

[toolboxchev]

Originally Posted by Stocker

Regardless of how good the gaskets are, I would help them do their job with a set of spreader bars. https://www.amazon.com/s/?ie=UTF8&ke...l_5nrfifmdd3_e

Those are not the good ones, I have half of a different set that are thick and made with a convex so when you tighten them down they spread the pressure instead of bend.

I picked them up in a junk yard. Need 4 more.

[Grumpy old man]

50 year old engines , Try 50 year old methods . Cork and Permatex #1 works every time . no more leaks

[OUbesto]

Originally Posted by Grumpy old man

50 year old engines , Try 50 year old methods . Cork and Permatex #1 works every time . no more leaks

Too late....already installed!

[BCOWANWHEELS]

Depends on how much blow by your engine has...............