Are rubber valve cover gaskets JUNK? Pic inside

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Nasty-LSX

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I did something I told myself I was not going to do. Put Chrome valve covers on. I put a weiand stealth intake
on the truck and then said to hell with it and bought Chrome valve covers on it. I went to COMPETiTiON SALES
I bought all the rubbers and breather and gaskets. When I got home and opened the box, they were rubber. I
cannot get this crap to seal and stop leaking. Is the rubber junk? Do I need the thick cork type? I will say
engine looks ten times better and runs even better than before with this intake compared to stock.

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squaredeal91

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I did something I told myself I was not going to do. Put Chrome valve covers on. I put a weiand stealth intake
on the truck and then said to hell with it and bought Chrome valve covers on it. I went to COMPETiTiON SALES
I bought all the rubbers and breather and gaskets. When I got home and opened the box, they were rubber. I
cannot get this crap to seal and stop leaking. Is the rubber junk? Do I need the thick cork type? I will say
engine looks ten times better and runs even better than before with this intake compared to stock.

You must be registered for see images attach
What kinda carb is that??
 

AuroraGirl

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FelPro cork gasket are the best , glue them to the covers with 3m weatherstrip glue .. No sealer on the heads Rubber gaskets are for the trash can .
i wouldnt use weather strip adhesive on your valve cover.
 

Nasty-LSX

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i wouldnt use weather strip adhesive on your valve cover.
I have actually seen that done before, it works!. I have never used rubber gaskets before so this sucks. I always
had cork with rtv on cover side and never had a problem. So this rubber gasket is junk. :happy160:
 

SirRobyn0

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It seems to me that like engine oil everyone has a different opinion of what is best. There's rubber gaskets, there's rubber gaskets with metal in the middle so they can't be pushed out, synthetic rubber, there's cork / rubber composite gaskets, then there is cork 5/32" or 7/32", there so many flavors of gaskets for these trucks it's ridiculous!

The thing is our trucks valve covers and the block surface is less than ideal. I mean who thought a rounded non-finished head surface and covers with 4 bolts in the middle was a good idea anyway lol. Well they rolled out of the factory with cork and it's what I have had the best luck with on tin covers. On aluminum covers rubber with the metal in them seems to work good and last a long time. Albeit I think aluminum covers look out of place. The main benefit of the aluminum cover is that they can be torqued down tighter. Tin covers can't take a lot of torque or they bend at the bolts.

So what I like to do is to make sure the bolt holes in the covers are flat and then use spreaders on the bolts. 5/32" cork gaskets glued to the covers with 3M weather strip adhesive or a strong spray adhesive like super 77. I like to use right stuff on the block side. Drive it 100 miles and check the recheck the tightness of the bolts. One down fall is that cork will shrink over time and can burn out if they get to hot. So every other oil change or so I'll check to see if they need to be tightened up a little bit. The 7/32" gaskets can seal warped covers better, but they seem to take a few more initial heat cycles and tightening before they seal up good so I like to use the 5/32" stuff unless there is an issue.

The biggest down fall to cork is the need for retightening as the cork compresses over time and relatively short life, but they are best at sealing an irregular surface which our trucks certainly have that.

Well I gave you a lot more than you asked for and you probably already knew most of it. I think we all have a preferred gasket and installation technique that is a little different, but works for the individual.
 

fast 99

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No matter what it will leak at some point. A 1950 poor design.

That being said I have had decent service glueing a cork gasket to the cover with weatherstrip and RTV on the head side. Set them on and lightly snug the bolts. Let sit overnight then do final tightening. Felpro may make a steel reinforced gasket, but I haven't used them.
 

bucket

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It seems to me that like engine oil everyone has a different opinion of what is best. There's rubber gaskets, there's rubber gaskets with metal in the middle so they can't be pushed out, synthetic rubber, there's cork / rubber composite gaskets, then there is cork 5/32" or 7/32", there so many flavors of gaskets for these trucks it's ridiculous!

The thing is our trucks valve covers and the block surface is less than ideal. I mean who thought a rounded non-finished head surface and covers with 4 bolts in the middle was a good idea anyway lol. Well they rolled out of the factory with cork and it's what I have had the best luck with on tin covers. On aluminum covers rubber with the metal in them seems to work good and last a long time. Albeit I think aluminum covers look out of place. The main benefit of the aluminum cover is that they can be torqued down tighter. Tin covers can't take a lot of torque or they bend at the bolts.

So what I like to do is to make sure the bolt holes in the covers are flat and then use spreaders on the bolts. 5/32" cork gaskets glued to the covers with 3M weather strip adhesive or a strong spray adhesive like super 77. I like to use right stuff on the block side. Drive it 100 miles and check the recheck the tightness of the bolts. One down fall is that cork will shrink over time and can burn out if they get to hot. So every other oil change or so I'll check to see if they need to be tightened up a little bit. The 7/32" gaskets can seal warped covers better, but they seem to take a few more initial heat cycles and tightening before they seal up good so I like to use the 5/32" stuff unless there is an issue.

The biggest down fall to cork is the need for retightening as the cork compresses over time and relatively short life, but they are best at sealing an irregular surface which our trucks certainly have that.

Well I gave you a lot more than you asked for and you probably already knew most of it. I think we all have a preferred gasket and installation technique that is a little different, but works for the individual.

Very well said. There's too many types of gaskets available and too many types of sealants, there's really no definitive answer. Especially when aftermarket chrome parts come into play.

With all that said, my favorite choice for this exact scenario is the Mr Gasket Ultra Seal gaskets. They are a cork/rubber hybrid and work very well. I have never used additional sealant with them, and in doing so, they are indeed reusable just like the description says. Basically if you use them and they still leak... you simply need better quality valve covers.

 

Octane

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I did something I told myself I was not going to do. Put Chrome valve covers on. I put a weiand stealth intake
on the truck and then said to hell with it and bought Chrome valve covers on it. I went to COMPETiTiON SALES
I bought all the rubbers and breather and gaskets. When I got home and opened the box, they were rubber. I
cannot get this crap to seal and stop leaking. Is the rubber junk? Do I need the thick cork type? I will say
engine looks ten times better and runs even better than before with this intake compared to stock.

You must be registered for see images attach
Rubber/steel framed gaskets work pretty good for me
 

ChuckN

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I’ll be the guy that will chime in and say that I really like the Fel Pro steel core rubber gaskets.

The biggest change for me though was getting away from using stamped tin/steel covers and going with more rigid cast aluminum covers- it is all I’ll use these days.
 

AuroraGirl

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I have actually seen that done before, it works!. I have never used rubber gaskets before so this sucks. I always
had cork with rtv on cover side and never had a problem. So this rubber gasket is junk. :happy160:
im just saying because of its use and properties, i wouldnt want that getting in my oil (like RTV in that sense) and if your gluing a rubber gasket to metal.. i feel at that point covers with strong construction and spreaders with a cork gasket will just work better lol
 

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