[stpltn250r]

Anyone fix this problem before? Crack goes from one little hole above crank snout to little hole beside crank snout. Follows along scooped out area. I did not press the new bearings in. I heated the area up with a heat gun and head the bearings in the deep freeze for days before installing. Do you think some kind of thermal expansion caused the case halve to break here?

 

[stpltn250r]

Here is a picture with no bubbles.

 

[volfan537240]

never seen anything like that

 

[DMoneyAllstar]

Nope, only thing I've seen close is cracking as a result of failure during bearing press (which I've done recently).

 

[John Tice]

A quick comment on cooling your parts: At 1 time I packed a Harley liner in dry ice in an attempt to shrink it some. The humidity was high and the sleeve attracted a layer of frost. Needless to say, the frost took up more space than the gain in the temperature drop. I’ve never tried that again but if your parts are taking on a layer of frost, you’ve probably lost the value of the temperature shrink, Maybe. Next time measure your parts, hot & cold.
Cracked cases: You should tear the engine apart and take a closer look. Does this case have an Iron insert? If not, after a welding repair, an insert would probably strengthen things up. Let your common sense help you decide what to do. I’d guess that the manufacturer needs to engineer some extra strength into the part.

 

[stpltn250r]

These are on stock cylinder engine. No stroker, crazy port timing or super high compression.

 

[John Tice]

Maybe their worth fixen
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