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Help! I can’t stop my coolant leak.

Discussion in 'Engine & Performance' started by Rob Goblin, Feb 11, 2020.

  1. eskimomann209

    eskimomann209 Full Access Member

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    Dunno haven’t seen ur welds. Im always up for weld porn!
    My background is fabrication and sanitary welding wine lines. And even that was a few years ago. I’m a rail roader now.
    I have done old oil pans for motorcycles that were out of production cast aluminum and soaked in oil. Had to sweat them out. But personally. I try to back purge everything I can. And I don’t have a high freq welder at home and I doubt he does too.
    And that being the case it’s probably cheaper to source another one!
     
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  2. shiftpro

    shiftpro Full Access Member

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    I'm just getting back into welding/fab... at 60 yrs instead of retiring I'm returning to my original and favorite trades.
    I recently purchased an Everlast 250EX... which I haven't even fired up yet... still ass deep in my home reno and shop additions. Hopefully by this fall
    I'll have shop phase 1 and 2 together... after that is shop phase 3 with my 4 post hoist.
    I've been collecting tools used and new for a few years now. New when on sale! It's taking a long time but the good thing is, I get to shop around and wait for great deals.

    I fixed aluminum intakes in 80's... not with tig but with mig. The typical damage are the 'ears' on the corners getting broken from over torquing or...
    dropping! I'll admit I've never repaired a cracked runner but I'm aware of the issues with this.

    And yes you're right, sourcing a new (new used!) intake would be cheaper than a repair job.... but I don't think your intake is broken. Hopefully..
     
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  3. shiftpro

    shiftpro Full Access Member

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  4. Doppleganger

    Doppleganger Supporting Member Supporting Member

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    I used to have issues like this on various 4-bangers with aluminum covers, housings, etc. Between pitting, ever so light warping and the utter crap quality of the gaskets, it got to the point I used RTV with their gaskets. If I applied then tested within 6hrs, I had a 60% chance it would eventually leak, weep or even wick again. If I let it set overnight, was about a 5% chance.
     
  5. eskimomann209

    eskimomann209 Full Access Member

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    I usually put a thin bead on the intake. Smear it with the ole finger put the gasket on. Smear some on the neck... hand tighten. Let it sit for 15 minutes come back and torque it to spec. Let it sit for 12 hours at a MINIMUM 24 being best. Then rock it.
    But that is a route taken when the gasket fails to seal on its own.
     
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  6. Snoots

    Snoots Supporting Member Supporting Member

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    Use a #2 Bastard file to check the flatness of the intake. Just a few strokes will show you any uneven spots. I wouldn't use plumbers dope. I'd stick with Teflon tape and use BRASS plugs.
     
  7. 82sbshortbed

    82sbshortbed Supporting Member Supporting Member

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    Can't go wrong with a good bastard file.
     
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  8. legopnuematic

    legopnuematic Supporting Member Supporting Member

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    A bastard file or A flat rigid sanding block works good and hit the thermostat housing on a piece of glass (or granite) with sandpaper on it to make sure its flat.

    I too have battled thermostat housings, I have found that the best solution is to find a cast iron water neck, but when I hopped my 76 up I got a GM 10108470 for $7 from summit and haven't had any leaks with it installed on an Edelbrock 2101 manifold.
     
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  9. nabeshin

    nabeshin Member

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    When I changed the thermostat I had test fitted the neck without gaskets and noticed it rocked slightly. Filed it with a smooth bastard and then hi-tack on both sides of the new gasket, no leaks.
     
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  10. eskimomann209

    eskimomann209 Full Access Member

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  11. ali_c20

    ali_c20 Full Access Member

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    This "cheap" thermostat housings suck. I had to rework the surface and the cast on every water neck I bought (7-20$) price range. I really don't like to have to fix or modify parts that should be bolt on out of the box but I'm definitely not paying 50$ for a non leaking housing.
     
  12. Octane

    Octane Full Access Member

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    I had an o ring type housing once that had the o ring groove cut to deeply so the thing would seal till the coolant got hot and then it would leak and spray coolant onto the manifold etc and make a mess.I removed o ring and used a gasket instead to fix it.
     
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  13. KS2506

    KS2506 Junior Member

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    If the engine is going to be replaced, JB Weld it to the manifold.
     
  14. CORVAIRWILD

    CORVAIRWILD Full Access Member

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    Run thicker coolant...
     
  15. mike broussard

    mike broussard Member

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    Just an interesting aside. I had an aluminum head with a crack in the combustion chamber to water jacket. My machine shop wouldn't touch it.
    I called Reher-Morrison and asked their opinion. He said nope. The weld would collapse and make a bigger hole.
     

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