Block cracks

[Chuck Sea/Tac]

Other than the top of the block, where are the common cracks found, when checking a block for rebuilding. I am using a block tester at 40#s.

[Tom Wesenberg]

40# sure sounds high, especially for an unpressurized system. I bought a block at an auction 20 years ago, but when I got it home I found a crack in the valve chamber, near the center.

[100IH]

Are you saying 40# of air pressure in a bare block on the stand and using good soap / bubble mix in a spray bottle. If there is a crack that leaks, you'll find it.

[Chuck Sea/Tac]

Yes, that's what the instructions say for pressurizing a bare block. It works great. So far I e tested 4 different blocks overnite and they all held. In fact the only leaks I've found were in the nipple to gauge connections.

[darrylkmc]

Chuck,

Look at the water jacket areas at the front and Inlet side of the block. Attached is a photo of a front repair l made on a freeze crack on a Model B engine more than thirty years ago.

At the time l used 1/8" solid brass pipe plugs, since that time Pete has changed my thinking to the use of solid Cast Iron pipe plugs.

Hope this helps.

Darryl in a beautiful Fairbanks

[Kohnke Rebabbitting]

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Originally Posted by Tom Wesenberg

40# sure sounds high, especially for an unpressurized system. I bought a block at an auction 20 years ago, but when I got it home I found a crack in the valve chamber, near the center.

Some Model T's crack there also .

Herm.

[Kohnke Rebabbitting]

Originally Posted by 100IH

Are you saying 40# of air pressure in a bare block on the stand and using good soap / bubble mix in a spray bottle. If there is a crack that leaks, you'll find it.

Many a crack are old ones, and don't leak, because of rust and old crack sealer. Block should be free of all rust, just to find a crack that will not leak under pressure testing.

After a block is boiled out, the block should be made sure that it is dry, as water in a crack will not show up a crack with a dry magnaflux.


Herm.

[Gunmetal blue2]

your block can be welded if you take it to the right person that knows what they are doing. We have welded high performance engines and they hold to gether.