Posted By: Hemi_Joel
nEED ADVISE ON CRACKED VALVE GUIDE BOSSES - 05/07/21 04:45 AM
In this chapter of the never ending saga of the unhappy Hemi, I have discovered some cracked valve guide bosses. On #6 intake, I screwed up the spring seat when I was using a comp cams seat cutter with a hand drill. 15 of them went perfect, but this one got cocked somehow and cut crooked. So I put it in the mill like I should have done in the first place and cut it deeper to straighten it out, but it broke thru into the intake port. So I had the seat welded up and re-cut it to the perfect depth using the Bridgeport. When I went to grind the weld drooble out of the port, I saw the cracked guide boss. Carb cleaner sprayed into the spring seat leaks into the port.
So I looked at the others and there is a few smaller cracks that don't leak when tested with carb cleaner. I've never had this before, so I'm not sure if I can just seal it up with some epoxy, or if this is a catastrophe waiting to happen and I need to remove the guide(s) and get it/them welded up. This motor is to much $$ to just throw it together and see how long it hangs together if this is a big risk. I need to know if it's completely safe to run, or not. If I have to do the big repair, the seats will have to be recut after the guides are reinstalled, and no one is going to do all that in a week so I will for sure miss the Midwest drags and lose my $500 entry fee. Does anyone have experience with this type of crack? What did you do, how did it work out? THanks, JOel
So I looked at the others and there is a few smaller cracks that don't leak when tested with carb cleaner. I've never had this before, so I'm not sure if I can just seal it up with some epoxy, or if this is a catastrophe waiting to happen and I need to remove the guide(s) and get it/them welded up. This motor is to much $$ to just throw it together and see how long it hangs together if this is a big risk. I need to know if it's completely safe to run, or not. If I have to do the big repair, the seats will have to be recut after the guides are reinstalled, and no one is going to do all that in a week so I will for sure miss the Midwest drags and lose my $500 entry fee. Does anyone have experience with this type of crack? What did you do, how did it work out? THanks, JOel