Page 3 of 3

Re: Cracked Block :-(

PostPosted: Tue Aug 21, 2012 5:13 pm
by gt4play
Some added clarification:

bridge47 wrote:-JB weld does not seal against pressure. Ever.

Although logic might dictate your statement to be 100% correct, there are proven instances where it actually has worked for others - for years on end. Regardless, my little JB Weld approach was not intended to act as a permanent solution, nor did I expect it would/could serve as such. It was indeed intended to be temporary just to get me through the summer (maybe a little longer if I was lucky).

bridge47 wrote:When your block starts leaking again(and it will),

It did - but not in the JB Weld patched area. The patch actually built pressure back into the coolant chambers, ultimately revealing even more fractures in the back of the block. I cannot say specifically where - at this point it didn't much matter to me anymore. I decided to take 'er off the road until I could ultimately source a replacement block, hence my latest post.

bridge47 wrote:Don't count on cold temps to push them out. Not what they were designed for.

Trust me, I wouldn't have deliberately disregarded the coolant mixture thinking these plugs (even if they were truly "freeze" plugs), would cover my butt in the event of freezing. Despite how positive I was that the mixture was proper, it apparently was not. Still kicking myself for this.

Re: Cracked Block :-(

PostPosted: Tue Aug 21, 2012 7:48 pm
by GT4_DRED
bridge47 wrote:When your block starts leaking again(and it will), find an old guy who has had experience welding small block chevy heads with high nickel content rod. This is a walk in the park for these guys.


X2..

Re: Cracked Block :-(

PostPosted: Tue Aug 21, 2012 8:01 pm
by gt4play
GT4_DRED wrote:
bridge47 wrote:When your block starts leaking again(and it will), find an old guy who has had experience welding small block chevy heads with high nickel content rod. This is a walk in the park for these guys.


X2..


Folks, I-bought-a-replacement-block.

After my new-found discoveries (mentioned already), there's no point in attempting anymore patchwork - regardless of how it's done.

Re: Cracked Block :-(

PostPosted: Thu Aug 23, 2012 3:14 pm
by bridge47
Wasn't trying to kick you while you're down.

Point of my reply was to help others in the same boat.

You did the right thing by getting another block. Even welding is hit or miss depending on who's doing the job.

Re: Cracked Block :-(

PostPosted: Thu Aug 23, 2012 11:56 pm
by Mafix
just to chime in on the new subject:
i've seen several blocks/manifolds welded. i've never seen it hold. but that's just my experience.
i've seen several aluminum things welded, never seeen an issue from the repair.

the cast welding seems to be very very hard to do. even very experienced welders turn away from it. interesting...

Re: Cracked Block :-(

PostPosted: Fri Aug 24, 2012 12:27 am
by MWP
After seeing the condition my block was in after having exactly the same crack, i very much doubt any type of repair (coolant additive, epoxy or brazing/welding) would hold for more than a few days.

The heat stresses in this corner of the block are huge!
When i finally pulled by block down (had been running it with the crack for ~4 months), the section that had cracked had a ~1mm lip on it. I was amazed it could deform that far.

Image

Re: Cracked Block :-(

PostPosted: Fri Aug 24, 2012 3:15 am
by gt4play
MWP wrote:After seeing the condition my block was in after having exactly the same crack, i very much doubt any type of repair (coolant additive, epoxy or brazing/welding) would hold for more than a few days.

The heat stresses in this corner of the block are huge!
When i finally pulled by block down (had been running it with the crack for ~4 months), the section that had cracked had a ~1mm lip on it. I was amazed it could deform that far.

Image


That's interesting. It's literally the same exact crack! Do you think yours is attributed to freezing (at some point)?

Re: Cracked Block :-(

PostPosted: Sat Aug 25, 2012 10:52 am
by MWP
Freezing... in Australia? :rofl: