Register now to get rid of these ads!

valve cover leaks

Discussion in 'The Hokey Ass Message Board' started by Al Baker, Aug 2, 2013.

  1. Just installed a Langdon rebuilt I6, 292cid, in my '54 Chevy car, from a 261cid, with a heavy chrome/aluminum/ribbed valve cover, using a high quality cork valve cover gasket.
    Full oil pressure Engine makes pressure in [high 40's psi]; valve cover uses 2 center studs instead of original 4 perimeter bolts. Head is Chevy original. At first oil squirted out onto driver side and over to inner fender, etc. - messy and annoying.
    Tightened and tightened and tightened until cover about to crack - engine now has about 900 miles since install and got the leak down to a small oozing out onto the head ledge but don't want ANY oil seepage.
    Could silicone/permatex both surfaces of the gasket/cover but that will become a later mess/difficulty.

    My question: can anybody recommend a specific valve cover gasket or other solution for this type of leak? Might there be a special vc gasket on the market that is best for persistent valve cover leaks on Inline 6, engines? This engine is making close to 300 hp so it's pushing oil around in there pretty good I suppose?

  2. Flop
    Joined: Jun 8, 2006
    Posts: 3,886


    id say give indian head a try !!
  3. slowmotion
    Joined: Nov 21, 2011
    Posts: 3,282


    Couple of things to try

    Double gasket

    Spreader of some type on the fasteners to distribute holding force more evenly

    OVER tightening does more harm than good, in my experience

    Dab of silicone to keep the gasket in position

    Just throwing a few things out there to try
  4. Thankx Slowmotion - all good - actually thought of 2 gaskets - right on about the over tightening - been there - but it's a persistent mental problem since childhood!
    Appreciate the advice.

  5. How are you using the 2 bolt hold down? Tom L. wont sell a 292 aluminum valve cover because he says there are none that don't leak. I bought his adapter to go from the 292 to the 216 style cover.
  6. Sometimes you just have to resort to using a gasket sealer. HRP
  7. Thanks Junkbike,
    Cover came with 2 studs that fasten to the rocker assy - are you saying Langdon sells a kit for this?
  8. pila38
    Joined: Mar 25, 2009
    Posts: 765


    I know you don't really want to, but if the problem really annoys you, I would use some silicone. It cleans up fairly easy and should end your leaking woes. Plus, you can retain the 2-bolt look you want.
  9. Paul
    Joined: Aug 29, 2002
    Posts: 15,532


    Roughen or remove the chrome at the gasket surface, use permatex non hardening gasket compound on the cover to gasket and dry between the gasket and head.
  10. GassersGarage
    Joined: Jul 1, 2007
    Posts: 4,727


    Just curious, are you running a PCV valve?
    ClayMart likes this.
  11. Thanks to all - all good suggestions - Keep them coming if any others - I will try and put the best of them to use and I do appreciate the input - it's what makes this forum so great.
  12. Paul
    Joined: Aug 29, 2002
    Posts: 15,532


    Chrome is next to impossible to get a good seal on
  13. The older I get the more I hate chrome.
  14. mustang6147
    Joined: Feb 26, 2010
    Posts: 1,847

    from Kent, Ohio

    That's what I was thinkin about askin as well.

    I also use Black rtv on race engines and street engines. It stays very flexable, and seals great. I also wipe down any surface with prepsol before I seal it....
  15. ......Exactly. Not only is it slick, but I think the chroming process tends to distort (warp) surfaces especially something as long as a valve cover. Put it on a surface that you know is absolutely flat and check for true.
  16. Gassers Garage;
    Yes I have a pvc valve setup at the top rear of the valve cover with a copper tubing vacuum line coming off a Fenton dual intake manifold and connecting at the back of the cover with a flexible line. The leak is mostly at the front-side edge of the valve cover on the driver side oozing back about a third of the length of the cover.
  17. Might help to make sure the drain back holes in the head are clean and clear.
  18. Yamabond silicon sealer, available at any Yamaha motorcycle dealer. Miracle stuff...

    Be very careful with Permatex or 'regular' silicon; you can 'glue' covers on so well that you'll damage them trying to get them off.
  19. tfeverfred
    Joined: Nov 11, 2006
    Posts: 15,792

    Member Emeritus

    This is a good cure. I remember in high school all the motor heads installing polished aluminum valve covers, oil pans and timing covers and soon after they leaked. Frustration lead to them being sold or tossed out.

    I think an article in Car Craft noted the cure as above. Also, stamped steel covers rarely leaked for me. On a 6 with just two studs to mount the cover, I'd try a stamped steel cover, rough it and a LITTLE film of silicone.

    DO NOT OVER TIGHTEN! I bet the torque on the factory cover is around 8#'s.
  20. Thanks again - all good advice - yea chrome is always a fit problem - we defy all the engineers and common sense when we hot rod. But I'm takin' this all in and will fix this little reluctant child - I swear.
    Here's a pic of the little troublemaker.

    Attached Files:

  21. Rusty O'Toole
    Joined: Sep 17, 2006
    Posts: 9,608

    Rusty O'Toole

    Check the cover is flat and straighten if necessary. Glue the gasket to the valve cover with a thin bead of silicone and set it on a flat surface to dry. When it is good and hard, at least a couple of hours, oil the gasket surface and put the cover on (O ya make sure the head surface is clean and smooth). Tighten down snug but do not over tighten. If it leaks try tightening a little more but not too tight,you will distort the cover. If no joy you may need silicone on both sides of the gasket as a last resort.
  22. Thanx Rusty - any special type of gasket recommended? Or do you suggest the standard cork one?
  23. unkledaddy
    Joined: Jul 21, 2006
    Posts: 2,865


    I use cork gaskets stuck to the valve covers with RTV sealant, filling and smoothing the V-grooves on the inside so oil won't pool there. I let them dry over night, butter the remaining side with Permatex Aviation Form-A-Gasket #3 and install. Using #3 the valve cover can be removed with the gasket intact later if necessary.

    Remember, fixing a leaky valve cover ain't rocket surgery.
  24. Ole don
    Joined: Dec 16, 2005
    Posts: 2,915

    Ole don

    Are you sure its the rocker cover? It may be a bit of blow by from the purty little vent. Try a diaper on it around the bottom.
  25. mopar210
    Joined: May 18, 2008
    Posts: 392


    I found a cure for this some years ago heard it from an old circle track guy I have done it on all my cars and it always works I even can remove and reinstall covers over and over again and no leaks clean and straighten the flange put a nice even coat of the gray high temp rtv on the flange ley skin up for about 20 minutes place a cork gasket CORK only on the cover get a nice flat surface board etc..... put the cover gasket side down and weight the top with something significant cement block etc... let sit for 1-2 days install cover I have done this on my last 3 builds (all adjustable rockers) and have had the covers off many times not 1 leak ! the fellow that told me this trick said they used it on the circle track cars and got many re uses out the gaskets

    Attached Files:

  26. bigdog
    Joined: Oct 30, 2002
    Posts: 685


    I had a persistant problem with leaks on chrome valve covers. Finally solved it by using the thickest gasket I could find. Roughened the chrome on the gasket surface and glued the gasket to the valve cover, then ran a bead os silicone on the sealing suface of the head. Do not over tighten. With a cork gasket you will need to recheck the tightness ocasionally.
  27. engine138
    Joined: Oct 5, 2007
    Posts: 2,062

    from Commack NY

    I asked my trunk monkey about this same problem. Im still waiting.
  28. Just use some quality sealer,having a valve cover with zero leaks is worth having to clean off old gasket 20 years down the road.
  29. 4decue
    Joined: Mar 15, 2017
    Posts: 14


    had the same kind of oil leaks from aluminum valve covers. .DOUBLE GASKETS? WASTE OF TIME. ...SILICONE? LOOKS CHEAP almost always turns out messy and not professional... felpro makes a real sweet gasket called seal rite. a bit expensive but made of neoprene rubber both sides ribbed with copper in center . they have not leaked a drop of oil. they are also re usable and don't require a lot of tourqe to keep them sealed.. warped covers will never seal correctly until they are made straight ,or u replace the covers. any chrome leaker covers i had were tossed years ago and replaced with aluminum , with the right gaskets they will seal.

Share This Page

Register now to get rid of these ads!


Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.