Cracked block woes

[rotorwrench]

Originally Posted by flatheadmurre

Why wouldn´t you find a leak in the exhaust port ?
My latest odd leak was in a casting fault in the oilfill of a 59ab...finding the bubbles in the water and locating the leak wasn´t the hard part...getting it fixed was the real pain in the rear.

It's not to easy to see up inside the ports. You can find which port but you may not be able to find (see) the crack. If it's way back in there, it won't be repairable. Might get some stop leak to fill it in but exhaust ports may not stay plugged due to the heat.

[Fourdy]

Tubman - It is the 8ba block.
Russ/40 - you feel my pain. We pressure tested the block twice using Dawn detergent and water sprayer. I wasn't sure if it could really detect a leak until seeing how much foaming occured from a minute leak from the bolt rubber gasket. Not being able to completely immerse the block, it was on an engine stand so it could be rotated. All surfaces, holes chambers were soaked and produced NO foaming. I could keep spending my Flatty $$'s trying to find and fix the problem or donate it to what we refer to as a "boat anchor" here in the great Northwest. Oh, I do have and used a borescope with no results. It sure is interesting to see what is inside these blocks.

I appreciate all of your comments and advice.

Fourdy

[Fourdy]

richard crow

I have bookmarked the zotight page for future need. I would be willing to try it before tearing the engine down. Now not worth the expense of putting it all back together for a possible fix. Thank you for the info.

Fourdy

[revkev6]

Originally Posted by Fourdy

richard crow

I have bookmarked the zotight page for future need. I would be willing to try it before tearing the engine down. Now not worth the expense of putting it all back together for a possible fix. Thank you for the info.

Fourdy

exactly the way I felt on mine....

[B-O-B]

Originally Posted by tubman

Just curious. What type block is this? Is it an 8BA, a 59A, or one of the earlier ones (99a, etc.). I've scanned the thread twice, and I don't believe it's specified.

From the picture it looks like an 8 BA.

[flatjack9]

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When I pressure test, I fill the block with water and then pressurize it to 60 psi.

[Mike51Merc]

Originally Posted by flatjack9

When I pressure test, I fill the block with water and then pressurize it to 60 psi.

Isn't 60 psi a bit much? A cooling system is pressure regulated by the radiator cap with most caps for flatties between 4 - 12 psi, depending on year.

I'd be scared to death of 60psi water in any container.

[flatjack9]

What's to be scared of? I am a plumbing contractor and the city water pressure in our house plumbing is 60 psi or even higher in some areas. I figure the block passes a test at 60 psi, it will surely be OK in the chassis.

[Kurt in NJ]

Water under pressure just sprays out, it's air --or other gases under pressure(including staem) that you worry about--just look at air compressor explosions, water is used for testing pressure vessels, it there is a failure it splits and leaks ---

[Bored&Stroked]

Given that the cylinder is washed down - like it was steam cleaned, that makes me think that the water must be coming into the cylinder - which is probably not an exhaust port leak.

My first guess would be a head gasket - did you carefully inspect the gaskets? What type are you using? Also, I'd do another pressure test on the block - but I'd poor hot boiling water into it - before you put on the water pump block-off plates. Get the block hot - see if that changes the story in #8.

Good luck! I know the sickening feeling of a cracked block - especially one that has had a lot of work done to it . . . keeps a feller up at night!

B&S

[Fourdy]

B&S
"BEST" gaskets sealed with copper gasket paint. The gasket had to be torn apart to get the head off then then putty knifed to clean the surface o stuck on material. I have used three sets of "big bore" gaskets on this block with two separate kinds of heads (merc and Edelbrock) with heating problems leading up to the final occurrence as as described before. I just can't make myself junk the block yet so I will set it aside for now and get my new engine put together. Anxious to get back o the road again.

Fourdy

[Mike51Merc]

Originally Posted by flatjack9

What's to be scared of? I am a plumbing contractor and the city water pressure in our house plumbing is 60 psi or even higher in some areas. I figure the block passes a test at 60 psi, it will surely be OK in the chassis.

I'd guess that at 60psi all the gaskets would be blown out, causing more trouble than it's worth.

[JSeery]

Originally Posted by Mike51Merc

I'd guess that at 60psi all the gaskets would be blown out, causing more trouble than it's worth.

What gaskets? I'm not aware on any gaskets involved when I pressure test, unless your referring to the neoprene between the block off plates and the block. If they can't hold 60 psi it is not a very good setup, that's for sure!

[bill3337]

I wouldn't junk the block until I knew for sure what the problem was. I think it's worthwhile to take it to a professional shop who can do the magnafluxing. I'd want to know what the issue is.

[flatjack9]

Originally Posted by Mike51Merc

I'd guess that at 60psi all the gaskets would be blown out, causing more trouble than it's worth.

I use a gasket cut out of some heavy duty rubber belting material about 3/16 thick and have never blown it out. I guess I better rethink my method.

[Dave/Green Bay]

Jack just tested 2 blocks for me a 35LB and a 8ba using his 60 pound testing method. The 8ba ended up having several cracks inside the exhaust posts. I wasted time and money pining the block before the test. Wish I had taken it to him before the money waste. His testing method does work. I was about to build the engine which would have been a complete wasted of money building what I thought was a good block. Thanks Jack for your help. Dave/Green Bay