Water pump gasket using RTV or other sealant?

Discussion in '6.9L IH & 7.3L IDI Diesels' started by DrCharles, Apr 14, 2018.

  1. DrCharles

    DrCharles Full Access Member

    Posts:
    303
    Likes Received:
    137
    Joined:
    Dec 18, 2017
    Location:
    West Plains, MO
    As I grumbled about in the "What did you do to your truck today" thread, my new water pump came with a torn gasket in the bag. I have to wait until tomorrow afternoon for a new one. The old one was super-hard, really stuck to the front cover, and had RTV red smeared on the pump side of it.

    It occurred to me that RTV, Hylomar, Permatex Aviation Sealant, Form-A-Gasket, etc. could be used to seal the machined surfaces and eliminate the gasket entirely.

    Has anyone done this successfully (i.e. no coolant leaks)? I've decided to wait for the replacement gasket, but still wondering about other options.
     
  2. nostrokes

    nostrokes Full Access Member

    Age:
    40
    Posts:
    177
    Likes Received:
    68
    Joined:
    Oct 13, 2017
    Location:
    Colorado
    I don't trust just gasket maker by itself. Always use the gasket material that is recommended. I use a very slight film of sealer on the gasket just to guard against any imperfections on either side of the castings.
     
    Duke57 and icanfixall like this.
  3. IDIBRONCO

    IDIBRONCO IDIBRONCO

    Posts:
    1,278
    Likes Received:
    327
    Joined:
    Feb 5, 2010
    Location:
    edmond, ks
    I'd have to second that one.
     
  4. Golden Helmet

    Golden Helmet Full Access Member

    Posts:
    223
    Likes Received:
    44
    Joined:
    Apr 13, 2015
    Location:
    Monterey County, California
    I don't know if you can do away with the water pump gasket entirely. When I did my water pump, I used the gasket it came with and Aviation Form-A-Gasket on both sides of the water pump gasket, plus grey RTV on the 4 special bolts. Been almost a year now and still no leaks.
     
    Duke57 likes this.
  5. 77f250diesel

    77f250diesel Full Access Member

    Posts:
    271
    Likes Received:
    4
    Joined:
    Feb 3, 2006
    Location:
    Florida
    Permatex Right Stuff, no gasket, no leaks.
     
    Last edited: Apr 14, 2018
  6. icanfixall

    icanfixall Official GMM hand model

    Posts:
    25,595
    Likes Received:
    376
    Joined:
    Apr 10, 2005
    Location:
    West coast
    My expericance tells me anything under the heat and pressure our cooling system is SHOULD have a gasket. On all my idi gaskets besides the head gaskets get a thin film of sealer of my choice. I like permatex ultra copper plus. The rear crank oil seal plate no longer has a gasket.. Just like the oil pan. Never had it...Never will.But of course we can purchase a oil pan gasket. But please don't use one. they guarantee will leak..then you pull the engine to replace it.
     
    Runningaford likes this.
  7. chris142

    chris142 Full Access Member

    Posts:
    2,440
    Likes Received:
    108
    Joined:
    Apr 15, 2012
    Location:
    SoCal
    The latest goops are very good. Like the right stuff already mentioned as well as the mega grey,mega black etc. Just don't use the old skool blue that always leaked. Both surfaces must be clean and dry. 1 drop of whatever will cause a leak.
     
  8. DrCharles

    DrCharles Full Access Member

    Posts:
    303
    Likes Received:
    137
    Joined:
    Dec 18, 2017
    Location:
    West Plains, MO
    I think I'll stay with a gasket. Got a good Felpro one today. Planning on a film of Permatex High-Tack on the pump side, and maybe a smear of Hylomar on the cover plate side so it'll come off again some day.
     
  9. IDIBRONCO

    IDIBRONCO IDIBRONCO

    Posts:
    1,278
    Likes Received:
    327
    Joined:
    Feb 5, 2010
    Location:
    edmond, ks
    The best thing I've found so far about using a skim of RTV on both sides of the gasket is that it seems to make the gasket easier to remove in the future.
     
    Kiwif150 and Thewespaul like this.
  10. Thewespaul

    Thewespaul Supporting Member Supporting Member

    Posts:
    3,189
    Likes Received:
    1,278
    Joined:
    Jul 27, 2015
    Location:
    Bulverde, Texas
    Yeah, makes cleaning the surface much easier, most the silicone peels off
     
  11. Simmonscoating

    Simmonscoating Full Access Member

    Posts:
    72
    Likes Received:
    23
    Joined:
    Apr 23, 2010
    Location:
    millersville md
    I second the use of Aviation Form-A-Gasket you can get it at napa, i use it on everything never had a leak(knock on wood)
     
  12. riotwarrior

    riotwarrior Supporting Member Supporting Member

    Age:
    53
    Posts:
    14,691
    Likes Received:
    361
    Joined:
    Sep 19, 2006
    Location:
    Cawston BC. Canada
    Elephant snot....aka avaiation form a gasket.....I put that ahit on everything...

    Best advice I offer...

    Clean...then

    Clean...then seeing its NOT ACTUALLY CLEAN

    CLEAN...AGAIN.

    think of a wound...if u get a cut and keep it clean it heals...but if u dont it swells gets pussy and leams

    Well the slightest bit of finger oil or contaminent makes it so the sealer wont seal...amd YOU WILL get a leak...

    Every surface has to be better than surgically clean and sterile.

    Just saying

    Did I mention clean

    Btw....i do NOT have leaks...EVER

    JM7.3CW Eh!
     
  13. Golden Helmet

    Golden Helmet Full Access Member

    Posts:
    223
    Likes Received:
    44
    Joined:
    Apr 13, 2015
    Location:
    Monterey County, California
    Like this? :D

    IMG_20170422_160038.jpg

    Started with a wire wheel, from there I hosed it down with brake-kleen. Then I broke out the coffee filters and rubbing alcohol and kept scrubbing until the filters came back clean, same method I use for cleaning computer CPU's and heatsinks. It's not overkill if it works ;)
     
    riotwarrior likes this.
  14. DrCharles

    DrCharles Full Access Member

    Posts:
    303
    Likes Received:
    137
    Joined:
    Dec 18, 2017
    Location:
    West Plains, MO
    I used a razor blade knife and gasket remover spray... then wiped a couple times with chlorinated brake cleaner (and picked off any remaining spots). It doesn't look near as pretty as your front cover but it's not leaking :)
     
  15. riotwarrior

    riotwarrior Supporting Member Supporting Member

    Age:
    53
    Posts:
    14,691
    Likes Received:
    361
    Joined:
    Sep 19, 2006
    Location:
    Cawston BC. Canada
    Chase threads blow em out...

    Ya looks spanky clean
     

Share This Page