Begle1 wrote:All heads crack no matter the EGT's. It's just more likely to be a problem with the 9mm heads, but it's still rare for the cracking to develop into leakage.
Cummins actually does have an exceptable crack also. since ive been workin at the shop im at we crack checked 4 cummins heads and they all had cracks in them and none ever caused an issue the peoples motors. the 9mm heads do supposedly crack more often but when i checked mine it only had 3 very small cracks in it. the 24v heads crack alot more cause of the closer proximety of the valves and injector holes. its not a problem and we have yet to have one be a problem. we actually had a 24v head that we stopped counting at 50 cracks and it ran flawless on the guys motor.
