I bought a 400 short block a while back and I've been taking it apart and cleaning it up.

In that process I discovered that one of the bolt holes for the a head bolt has a crack running to a coolant passage right beside it.

I thought I'd get opinions on the board to see if I should worry about it, before I drag it to a machine shop.

 

yeah either you can weld it and machine it or trash the block

 

Hmm... how pricey will that be?

 

I would find another block. The amount you are going to spend to get that fixed will be close to finding another bare block, and I just woulnd't feel comfortable building something that i know potentially could have a problem and may end up being torn down again later. Just my $ .02

 

You might want to "drag it off to a machine shop" anyway, if for nothing else than to Magnaflux or ultrasound the case to see if there are any other hidden cracks or stress points. If it is a single crack with no other problems, weld, stress relieve, and machine the hole. If there are more problems....

 

Pretty comon problem, usually results from over-torquing the head bolts and then overheating the motor.

Like ede said, it's repairable, that's not a big deal as repairs go and not very expensive. Probably a whole lot less than a new block. Sometimes they fix it by drilling the deck and putting in a pipe plug, then drilling and tapping that.