My car kept leaking coolant, the engine is a freshly built rod/piston setup 0 miles on it not sure if I should weld it and call it good or scrap the block and have another one machined. Opinions?

 

Get a new one since you already have internals and save money down the road later

 

yeah the only reason I am tempted to weld it is the fact that the rotating assembly pulled out of the engine had no signs of any kind of side loadings its as if the crack came from a wreck or something. thrust bearings were fine, mains/rods were fine, piston skirts had no signs of abnormal wear or anything.

 

Why not just weld it? what do you have to lose from trying?

 

My thoughts exactly

I wouldnt recommend a home remedy unless you know what you're doing. To weld the crack properly, you'll need to bevel the edges of it and then fill the gap. You could ask for advice in the Welding/Fabrication forum OR i can move the thread for you.

 

Wouldnt it cause catastrophic engine damage later on if it failed? What kind of block is it OP?

 

Take it to a machine shop they can weld it for you and test it make sure its not gonna fail...atleast right away

 

Where is this crack at? Can you take a larger, zoomed out picture and highlight the crack..?

 

Schister asked the perfect question it really depends on where the crack is situated.Most likely the motor will have to be dissasembled anyway to prep both sides of the crack for welding.It might be easier to just get another block.The weld will also have to be checked on the inside to make sure it has good penetration and that there is nothing that can break off causing internal damage later.

 

Is that at the bottom of a head bolt boss?

 

it is, I think the old owner tightened a head bolt down with fluid in the hole, it's a Z6 block. After talking with a few machine shops local as well as a few fab guys I know they all seem to believe it can be done without removing the cylinder head, the crack only leaks under ~20 psi of coolant system pressure which I know is over what they run. I am going to go ahead and try welding it but will probably throw another block in the machine shop at the same time to have it ready just in case something goes wrong with this.



the crack is settled along the top ridge that you can see in this picture that is parallel with the two upper rear main seal bolts. I was told to run a few gallons of water through the block with the pressure tester to clean out any traces of coolant and then it could be welded. Thanks for all the replies.