Engine rebuild. Use gasket sealant or not?

Discussion in 'Engine, Fuel and Exhaust' started by sincityharley, Apr 2, 2011.

  1. sincityharley

    sincityharley Member

    Im doing a top end rebuild on a 2002 Heritage Softail EFI. Im going to start putting it back together tomorrow. I was just wondering if I am supposed to be using any gasket sealant with the new gaskets that I am going to use?
  2. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

    You shouldnt need any sealant with proper gaskets
    gasket sealant was something i used in my younger days when i would re use the old gaskets on badly molested old engines

  3. Iceman24

    Iceman24 Well-Known Member

    fin's got it - bad habit I learned from my "frugal" dad and have since learned to "always" get new gaskets & they'll seal fine...stay away from "form-a-gasket"...bad stuff. Weekend mech re-built my son's car & used it & now I spend time in driveway sopping up oil w/speedy-dry. That's what you get with lowest bidder - he learned his lesson...;)
  4. R_W_B

    R_W_B Senior Member

    I agree with Brian and Iceman although I deviate sometimes if it's an area or part that is hard to hold the gasket in place during assembly. A THIN gasket seal adhesive works good here, OR on a surface that has been scratched up and doesn't seat the gasket well.

    Don't use any of the thick goop gasket stuff though (like we all did when I was a kid, during the last Ice Age) That stuff is a mess and I have seen them leak even with it used.

    I heard a lot of folks talking about their HD Oil Cooler adaptor leaking, not sure what the problem was but some did leak. When I put mine on I used the Permatex thin gasket seal adhesive on it.

    It's like a very thin coat on the part and the gasket and then you wait on it to get slightly tacky before assembly. Worked great on holding the thick heavy gasket in place while I put the adapter on. Anyhow my Oil Cooler never leaked a drop, not even any residue at all. Anyhow that's my 2 cents worth.
  5. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

    No short cuts! Use only gaskets, orings, seals where specified. Check mating surfaces for "flatness" and that the parts mate well. Machine or replace poor mating parts. Covers should be checked to make sure they are not warped. Only use a liquid sealant where specified in the Factory Service Manual (like the mating halves of the engine case).

  6. ultra...good

    ultra...good Banned

    I'll also use a very thin dot here or there to hold a gasket in place while assembling something. Would not use it as a gasket or put a bead on a surface. If they surface is that porous, I would bring it in to have it machined to where it is both relatively smooth, and straight.

    NEWHD74FAN Experienced Member Retired Moderators

    Always new gaskets and o-rings dry as specified...use "all thread" as guide/alignment tool to ensure you put on parts straight and true. As Ultra...Good says, only use a bit of sealer to hold gasket to one surface if no way to ensure alignment. As BUBBIE would say...just my way...:D
  8. Jack Klarich

    Jack Klarich Guest

  9. flh canuck

    flh canuck Active Member

    I agree with whats already been posted here.

    The new gaskets and o rings are very good quality and don't require any sealant if put together properly and mating surfaces are true.

    When I recently re-did my top end, I was impressed with the quality of the parts and machining as supplied from the motor company. Very heavy castings etc. with wide sealing surfaces.

    Biggest issue is making sure everything is clean, clean, clean (with extra emphasis on clean....) prior to re-assembly.

    Torque carefully in proper sequence as per specs in the shop manual and make sure you use a good quality torque wrench.

    Take your time and you should end up with an oil-tight engine once done.