No valve cover gaskets!
#1
Le Mans Master
Thread Starter
No valve cover gaskets!
Replaced, should say installed valve cover gaskets on my 1980. There were no gaskets, just a thin layer of red RTV silicone. Is this how they were assembled back then with no gaskets? Is the oil pan on the same way with no gasket? Do the valve cover spreader clamps help prevent leaks, look dumb, but if they help, I am all for it. Thanks!
#2
Team Owner
Member Since: Sep 2006
Location: Westminster Maryland
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Hi CT,
The engine that was originally in your 80 used both valve cover and oil pan gaskets.
Regards,
Alan
The engine that was originally in your 80 used both valve cover and oil pan gaskets.
Regards,
Alan
Last edited by Alan 71; 08-30-2016 at 08:37 AM.
#3
Le Mans Master
Thread Starter
Thanks! I thought that would be the case, previous owner attack! It was very well done, with no visible evidence of excessive RTV. Dumb, RTV is about as expensive as cork gaskets.
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Aggitated Monkey (08-30-2016)
#5
Burning Brakes
"valve cover spreader clamps" are a useful item when using the original SBC thin tin valve covers..when using aluminum thicker valve covers not so much of an issue.
#6
Race Director
Funny that you mention this. I certainly would have thought the same thing but a surprising number of newer cars were done this way from the factory. Saturn, in particular, did a lot of this on some motors that had 100k mile service intervals. They didn't leak either.
#7
Safety Car
Funny that you mention this. I certainly would have thought the same thing but a surprising number of newer cars were done this way from the factory. Saturn, in particular, did a lot of this on some motors that had 100k mile service intervals. They didn't leak either.
That's not the case with early style SBC valve cover rails which are left as cast on the cyl head with stamped sheet metal rocker covers.
Very different designs and because of casting irregularity and deformation in sheet metal stampings, early SBC's require gaskets to seal properly.
Will
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marshal135 (08-30-2016)
#8
Burning Brakes
small block's in the late 70's/early 80's did indeed come from the factory with red RTV for valve cover sealing (and some timing covers) and not gaskets. I have worked on several of them when new. none were corvette's, but passenger car and light trucks, so I can't say for sure if the 'vette motors were assembled that way, or if someone swapped your motor. It is VERY difficult to apply RTV that way without pneumatic guns, and the modern sealant in the mousse tubes is not red that I have ever seen...usually blue or grey...you could tell by pulling it off if it was done by hand with several start/stops from tubes, or a continuous even flat bead done from a factory gun...
#9
Race Director
Saturn (and most all modern engines) are dealing with 100% machined surfaces..... both the head and cam cover are Cast Aluminum and have machined flat sealing surfaces.
That's not the case with early style SBC valve cover rails which are left as cast on the cyl head with stamped sheet metal rocker covers.
Very different designs and because of casting irregularity and deformation in sheet metal stampings, early SBC's require gaskets to seal properly.
Will
That's not the case with early style SBC valve cover rails which are left as cast on the cyl head with stamped sheet metal rocker covers.
Very different designs and because of casting irregularity and deformation in sheet metal stampings, early SBC's require gaskets to seal properly.
Will
Last edited by CA-Legal-Vette; 08-30-2016 at 01:04 PM.
#10
Le Mans Master
Thread Starter
small block's in the late 70's/early 80's did indeed come from the factory with red RTV for valve cover sealing (and some timing covers) and not gaskets. I have worked on several of them when new. none were corvette's, but passenger car and light trucks, so I can't say for sure if the 'vette motors were assembled that way, or if someone swapped your motor. It is VERY difficult to apply RTV that way without pneumatic guns, and the modern sealant in the mousse tubes is not red that I have ever seen...usually blue or grey...you could tell by pulling it off if it was done by hand with several start/stops from tubes, or a continuous even flat bead done from a factory gun...
#12
Team Owner
#13
Le Mans Master
Thread Starter
I looked at a shop manual for changing the valve cover for a 1980. They do say to use RTV on the valve covers. Who needs to read a manual to change valve cover gaskets? I guess I do! I did install felpro rubber gaskets. Probably leak like a sieve now!
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ratvet (02-28-2020)
#14
Team Owner
#15
Racer
Spent two years flat rating on the line at AD Anderson Chevrolet in Baltimore Md. In 1978 and 79. No gaskets rtv only. No problem if you want to use gaskets though.
#16
Team Owner
In that timeframe, GM was starting to get beat out by the Japanese manufacturers. I suspect (but don't know) that some of the Japanese engines were being sealed like that and GM did some 'tinkering' with assembly processes.
Of course, once robotics made it to the factory floor, sealants are today's 'gaskets'.
Of course, once robotics made it to the factory floor, sealants are today's 'gaskets'.
#17
Melting Slicks
I have been using fel pro rubber gaskets with the metal centers along with RTV and have finally stopped the leaks.