Page 1 of 2 12 LastLast
Results 1 to 10 of 19

Thread: Sealant for valve cover gasket?

  1. #1
    One Track Mind dduelin's Avatar
    Join Date
    Feb 2006
    Location
    NE Florida
    Posts
    5,962
    Tip Overs:
    08
    2014 Miles:
    009370

    My Gallery

    Sealant for valve cover gasket?

    I had trouble getting the LH valve cover gasket to not weep or leak at the semicircles at the front both times I have had it off for valve checks. Both LH semicircles leaked again this last time and I pulled that cover off Sunday to fix it. I discovered I mucked up the little sealing ridges that mate against the cylinder head when I removed the RTV sealant I resorted to last time so I ordered a new gasket. Ouch! The service manual says not to use any sealant except at the semicircles but doesn't say what type. The RH side sealed fine with Hylomar which is easily removed later but I resorted to high temp RTV silicone on the left one after Hylomar leaked. I damaged the gasket digging at the silicone to remove it. I learned later that letting the gasket sit in a container of gasoline softened the silicone enough to easily remove it but I damaged the gasket before then.

    Anyway - the Q is what does Honda use to glue the new gasket into the valve cover? It appeared to be a clear sealant with light adhesive properties applied to the upper surface to glue and seal it into the valve cover but it let go easily when the gasket was pulled out of the cover. The gasket's lower surface is designed to seal against the head without any sealant except at the semicircles. Honda techs told me not to use any sealant at all as the semicircles normally seal up without any problems but the upper surface is definitely glued in place. They never remove them from valve covers so had no clue what to use.

    Dave
    Honda SC51
    Honda NC700X
    Honda Elite 80

  2. #2
    Matt Kaminski UNTMatt's Avatar
    Bike
    2006 ST1300
    Join Date
    Mar 2006
    Location
    Fort Worth, Tx
    Age
    43
    Posts
    5,888
    My Gallery

    Re: Sealant for valve cover gasket?

    Hondabond HT on the semi-circles

    I've not noticed any glue on the gaskets of our ST. They pull off w/o any issue.
    Last edited by UNTMatt; 04-08-2008 at 08:25 AM.
    "Life is always a choice between greater and lesser risks -- zero risk is not an option." John Stossel
    "Complaining about the heat in Texas is like complaining about water for being wet." Reliant Energy

  3. #3
    SISU an inner spirit dannyk's Avatar
    Bike
    05 ST1300
    Join Date
    Dec 2004
    Location
    U.P. of Michigan, Winter, Water, Wonderland
    Age
    66
    Posts
    1,419
    My Gallery

    Re: Sealant for valve cover gasket?

    Most likely hondabond to stick them to the valve cover, I use rtv silicone for the front knuckles, never had them leak with that. I had to pull the left side after my first ride from new as it was leaking there, no sealant from the factory on that side, but I won't re-assemble the covers without using sealant on the knuckles.

  4. #4
    R.I.P - 3/20/2011 alan's Avatar
    Bike
    ST1300
    Join Date
    Dec 2004
    Location
    Ottawa Lake, MI
    Posts
    1,426
    Tip Overs:
    4
    My Gallery

    Re: Sealant for valve cover gasket?

    I've used the same silicon sealant that I use in my bathtub to seal the half moons on the valve cover. I have also used the special automotive silicon sealant on the covers and found no difference between the two.

  5. #5
    snowmoer's Avatar
    Bike
    04 ST 1300
    Join Date
    Feb 2005
    Location
    Yucca Valley, CA
    Posts
    863
    Tip Overs:
    1
    2014 Miles:
    002752

    My Gallery

    Re: Sealant for valve cover gasket?

    I used the orange RTV sealant on the semi-circles only, no leaks.
    Dan

    04 ST 1300 2012 GL 1800 Gold Wing 1988 NX 650 1988 GL 1500 Gold Wing
    STOC 5926 AMA Life

  6. #6
    bmcdonau's Avatar
    Join Date
    Mar 2007
    Location
    Texas
    Age
    57
    Posts
    2,765
    My Gallery

    Re: Sealant for valve cover gasket?

    Be careful with that RTV. I've spent a lot of time wrenching on bikes and RTV is not generally recommended for sealing rubber gaskets. If you put too much on the surfaces it will squeeze out inside the engine. Sooner or later that piece will come loose and can plug up oil passages. I've taken engines apart that were full of sealent in the oil galleries and pickup screen. I use gasketcinch which is a thin adhesive that just makes the valve cover easier to put on by holding the gasket in place. It really doesn't have any sealing properties. I think Hondabond is the same type of material.
    1970 Honda SL-100, 1974 Honda XL-350, 1983 Honda CB1100F
    2007 HD FXDL, 2008 GL-1800, Triumph Trophy SE

  7. #7
    Ventura Highway
    Join Date
    Feb 2005
    Location
    timbucktu
    Posts
    5,104
    My Gallery

    Re: Sealant for valve cover gasket?

    Toyota makes a oil sump RTV-type material that's the best I've seen. On many of their cars including my daughter's '97 Tercel, there's no oil pan gasket, you just use this stuff. I spread as thin a film as I possibly can in those areas Honda says to seal and it never leaks. In addition, I've had the same tube for a couple of years now and it hasn't dried out and set up in the tube like virtually other product I've tried.

    I would be wary of using silicone sealants not intended for automotive use. Silicon, a breakdown product of the silicone (with an "e" at the end - important distinction) can apparently foul various sensors in the engine. Look for an RTV that says it's "sensor safe" on the label.

  8. #8
    One Track Mind
    (Threadstarter)
    dduelin's Avatar
    Join Date
    Feb 2006
    Location
    NE Florida
    Posts
    5,962
    Tip Overs:
    08
    2014 Miles:
    009370

    My Gallery

    Re: Sealant for valve cover gasket?

    Cool, thanks everyone. Today I went by the Honda auto dealership I worked at twenty years ago and asked the single remaining tech that was there when I was there what to use. He gave me a half used tube of Hondabond.

  9. #9
    Natural Rider Enhancement Blrfl's Avatar
    Bike
    Fast Blue One
    Join Date
    Aug 2005
    Location
    Northern Virginia
    Age
    45
    Posts
    11,786
    Tip Overs:
    1
    My Gallery

    Re: Sealant for valve cover gasket?

    Late to the party...

    I've used Permatex #85409 Ultra Rubber Gasket Sealant/Dressing several times successfully.

    --Mark
    Wizzzzzzzzzzzz What's a Blrfl? ... Shameless plugs: STWiki

  10. #10
    curmudgeon's Avatar
    Bike
    still deciding
    Join Date
    Dec 2004
    Location
    Bainbridge Island WA
    Age
    71
    Posts
    1,128
    My Gallery

    Re: Sealant for valve cover gasket?

    Had a leak on right valve cover after a valve check and found a small part of the rubber heat guard trapped under the gasket. OK so I bought a new gasket and installed it using Honda Bond HT on the semi circles. After a 170 mile ride Sunday noticed oil streaking on the lower fairing. Ran it this morning and a small streak of oil started coming out of the upper semicircle.

    So before trying this again any words of wisdom? Could I have used too much sealant???
    Anybody add a little extra torque to the cover bolts?

    Thanks for any help.
    Phil D.


+ New Posts
Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •