743B ,possible cracked head

[jim743]

I have a 743b that had been run low on coolant and blew out the head gaskets. It had been smoking white. Had checked exhaust manifold temp with a laser gun and found #2 cylinder running at lower temp. Shut off engine and returned to hydraulic locked cylinder. I remove the injector to discover the cylinder was full of coolant. Removed head and found a bad gasket, but am concerned about a possible cracked head. I see there are many new heads available for the Kubota V1702. Are these prone to cracking? Where are the common areas to look at for failure? I also checked compression on 1,3&4. Was getting 265,240 &260. I am suspecting that the rings got overheated and lost tension. what is acceptable compression on cold engine? Thanks

 

[Tazza]

They are prone to cracking.
Look between the valve seats and into the pre-combustion chambers. You may be best to take it to an engine re-conditioning place and get them to pressure/vacuum test it so you know it's good.