Coolant drip - Chevelle Tech
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post #1 of 7 (permalink) Old Aug 28th, 18, 12:11 PM Thread Starter
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Coolant drip

relocated from old thread -

Originally Posted by Dave427 View Post
You need to remove the motor mount bolt to make sure its the cause of your coolant leak.
Hopefully you didn't use too long of a bolt and bottomed out the thread and cracked something, probably not?
Its a patch if thats where its coming from it to drain the coolant pass that point clean everything up and put some tephlon paste on the motor mount bolt and re-install.


Was just looking at this thread. I just had new motor mounts installed on my 396 and apparently shop used too long of bolt and cracked the engine block, 1/4" long crack.

They cut a v-groove in the crack and welded it then pressure checked it.

Said that it should hold because it was on the cooling side(coolant leak).

I can't believe shop didn't check length of bolts(old vs new) before installing.

Any thoughts on whether this repair will hold and any recourse with the shop?

Last edited by Mike; Aug 28th, 18 at 3:25 PM.
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post #2 of 7 (permalink) Old Aug 28th, 18, 2:01 PM
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Re: Coolant drip from motor mount

You would probably have been better off starting a new thread and then just refernced this OLDER one but you're new here so.Anyways Welcome to TC.
IMO the motor mount bolts sit in a sort of raised up area is that what cracked ? Did the crack go amywhere near the freeze-out plug ? Was there any coolant leaking ?
If they drilled a stop crack hole and repaired it properly I would say don't worryabout it but welding cast iron takes a skill that needs to be done by someone with experience in that kind of repair. So I hope someone who has had experience with having something cast iron welded chimes in.From articles I have read about cast iron welding it also needs to be pre-heated to be successful.
I hope for your sake it holds,Good Luck.

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post #3 of 7 (permalink) Old Aug 28th, 18, 2:54 PM
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Re: Coolant drip from motor mount

For a cast iron repair of that sort wouldn't it be better to braze it?

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post #4 of 7 (permalink) Old Aug 28th, 18, 3:25 PM
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Re: Coolant drip from motor mount

Originally Posted by 71350SS View Post
You would probably have been better off starting a new thread and then just refernced this OLDER one

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post #5 of 7 (permalink) Old Aug 28th, 18, 4:01 PM
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Re: Coolant drip

Sounds like they did ok, it all depends on the quality of the cast iron. Some you can weld, some you cant.

I was a welder in another life, still am but just for myself and friends. Ive welded up a couple dozen blocks with broken water jackets.
Rough procedure is to drill a stop hole, use a carbide cutter to cut a v in the crack, preheat, weld with nickel rod, post heat, stress relieve.
I had 2 that I could not weld up because of poor casting material. You know instantly because the block will pop and another crack will be right next to the weld. Usually the popping will happen in post heat or stress relieving.

If you dont trust the weld have it dye penetrant tested.
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post #6 of 7 (permalink) Old Aug 28th, 18, 4:37 PM
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Re: Coolant drip

If they know what they are doing with cast iron it should be ok. If its going to leak it will probably do so pretty quickly.

Personally I would have used Loc-n-stitch pins I think they are more reliable in cast iron especially in the side of a block that expands and contracts a lot.

I would absolutely make sure there is a statement on the work order that the block was cracked by them and they will warranty the crack repair.

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post #7 of 7 (permalink) Old Aug 29th, 18, 5:58 AM
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Re: Coolant drip

It will be a case of wait & see...

A prayer each night to your favourite saint might also help....
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