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valve cover gaskets

Discussion in 'The Garage' started by barneybasher1010, Apr 8, 2006.

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WHICH VALVE COVER GASKET IS BETTER CORK OR RUBBER

  1. RUBBER

    66.0%
  2. CORK

    34.0%
  3. THE CHEAPEST YOU CAN GET

    0 vote(s)
    0.0%
Multiple votes are allowed.
  1. barneybasher1010

    barneybasher1010 1/2 ton status

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    Which valve cover gaskets are better rubber or cork? How about thickness?
     
  2. 4xcrazy

    4xcrazy 3/4 ton status

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    I have never had any good luck with the rubber gaskets, seem to leak all the time.

    I if i remember, there are like two ot three differences in thickness, i just use the stock type thinner ones, light coating of RTV on the valve cover to help it stick, and a VERY, VERY clean surface on the heads.

    I have had problems with chrome covers leaking,,,bad, i think on those you have to use the thin gaskets,,,and have alot of luck.:D
     
  3. 78Suburban

    78Suburban 1/2 ton status

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    I bought the economy line cork felpro's the other day, I'll let ya know how they work once I put them back on...in the mean time I've got some slight issues to address under those valves covers :haha:
     
  4. AKbigsub

    AKbigsub 1/2 ton status Premium Member

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    Felpro makes a rubber/metal anodized(sp?) set that I use. They have never leaked and unlike cork and/or rubber, you can re-use them and re-torque them if the do leak. The are spendy but are the last ones you'll ever need.
     
  5. Chevy305

    Chevy305 6 Lug 14bsf Status Premium Member GMOTM Winner

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    I have cork gaskets on there and a light bead of RTV and the suckers haven't leaked in the least.
     
  6. 1-ton

    1-ton 1/2 ton status Premium Member

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    That is what I used on my last valve cover job I did on my 1985 K30 Duallie. I was able to get a set of them pretty cheap from Summit.com for about $21 with shipping and everything.
     
  7. diesel4me

    diesel4me 1 ton status Premium Member

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    rubber...

    If I have the dough,I opt for Fel-Pro rubber ones,and glue them to the valve cover with RTV or 3M Weatherstrip Adhesive (the yellow snot)..then put a layer of wheel bearing grease on the other side that touches the head,so it wont stick..you can pull the covers many times and not have to replace the gaskets that way..

    But I've used cork cheapies with good results too,just use some RTV black on both sides..the main reason the valve covers leak is because they get overtightened and the covers flanges get warped all to hell..I hammer them flat on a block of wood,paying special attention to the bolt hole areas..those "load spreaders" work wonders too,the stock GM ones aren't long enough..:crazy:
     
  8. CB77GMC

    CB77GMC 1/2 ton status GMOTM Winner

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    Not sure where I stand on this one. Right bank is cork fel-pro. Left bank is Red RTV only. Oh and a set of fel-pro rubber gaskets sitting on tool box. :haha:
    So I would say " User Prefrence ". Any type done right will work.:D
     
  9. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    Cork are far superior to rubber, the rubber will harden over time and then crack and leak like hell. I always use cork and never have an issue. The later engines with the center bolt valve covers use a RTV type rubber gasket that seem to be pretty good but you can't use them on the earlier perimeter bolt heads.
     
  10. 4xcrazy

    4xcrazy 3/4 ton status

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    BTW, you have failed to follow the CK5 poll/post rules here buddy,,,there is no NEKKID option :p:
     
  11. 76zimmer

    76zimmer Flyin Rat Premium Member GMOTM Winner

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    I've had good satisfaction with Cork 5/16th thick. Just don't tighten them down more than snug. Make sure the valve covers are not warped also. I really like the cork rubber combo ones though, they seem to hold up to heat better than cork, or rubber.
     
  12. Blue85

    Blue85 Troll Premium Member

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    I thought SBCs were supposed to leak oil...
     
  13. big dan

    big dan 1/2 ton status Premium Member

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    Ive never had good luck with rubber or cork. Maybe I just dont know how to use them. Now I just use RTV and have a mess to clean up everytime I have to take off the valve covers but no leaks.
     
  14. mouse

    mouse 1/2 ton status

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    I'm glad I'm not the only one who can't seem to seal them...I will try with "The Right stuff" next time. Last year I went through 5 sets of gaskets, cork, rubber, rubber with steel...all leaked within a month or so. I changed to cast aluminum covers and they lasted about 6 months.

    Now the engines apart for a cam change....maybe I can get them to stop leaking.:doah:
     
  15. Storm Trooper

    Storm Trooper 1/2 ton status GMOTM Winner

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    I never have a problem sealing either of them and never have a leak.
    Dump the RTV and use Permatex High Tack. Even if you use it on the rubber ones, you can still remove them, clean them and respray.
    I hate leaks, that's why I avoid them (leaks) all together.
     
  16. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

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    I hate leaks too, and finally got em beat on my old smallblock by swapping on a set of cast aluminum valve covers. They're rigid and they're flat...and that is easily half the battle IMO. Because they're rigid you can torque the bolts down a little more and put some good clamping pressure on the gaskets.

    Rene
     
  17. mouse

    mouse 1/2 ton status

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    I changed to cast aluminum a year ago too...still got leaks. I think its coming through the bolt holes.
     
  18. nad

    nad 1/2 ton status

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    I just pulled my valve covers a few days ago to find 2 brand new looking rubber gaskets. The only problem I found is that one is slightly torn. So I will be buying a new set anyway. Now I've gotta just pay attention to what kind wins this debate and base what kind I buy on that ;)
     
  19. mrk5

    mrk5 The Sticker Guy Moderator Vendor GMOTM Winner Author

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    True that. I'll second your motion.

    It's when they stop leaking that you should worry. That means you have no more oil!!

    But in all seriousness, I'll second what Rene said. Cast aluminum covers help alot. Especially since I think a lot of us have a tendancy to over-torque fasteners.

    The first 350 I ever rebuilt, I snapped a head off a valve cover bolt. I think I may have been applying too much torque.:rolleyes:
     
  20. mouse

    mouse 1/2 ton status

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    I agree, my 350 is only happy when it can mark its territory!
     

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