Thread: My 1984 K10 - LM7 swap!!

Broken heads on exhaust bolts are common enough on these engines. My 2000 pickup had two broken and when looking into it, I found a lot of information saying that the bolts were soft. I spoke to a machinist I was using for 3800 stuff at the time and a few GM techs. They said they heat the bolt a few times to get the dissimilar metals to come apart, and or weld a nut on the end of the bolt in order to spin it out. Doesn't appear it's that tough to get them out. I didn't get around to it since I'd have had to taken over a decade old exhaust off and it didn't effect the truck. For less than a minute you'd hear very little noise that went away the moment the engine started to get some heat.

Originally Posted by Scottydoggs

you check to see if those are the crappy heads that are prone to cracking?

I have not. I didn't even know there were ones prone to cracking. I think I'm going to have an idle day or two coming up soon here while waiting for parts. I'll do some research then.

moving right along i see. soon will be pics of the old engine coming out and test fitting of the 5.3.

Man, that will be nice. First I have to get the motor back together though. I really want to run this one on the stand and grab some video this time.

Originally Posted by BillBoost37

Broken heads on exhaust bolts are common enough on these engines. My 2000 pickup had two broken and when looking into it, I found a lot of information saying that the bolts were soft. I spoke to a machinist I was using for 3800 stuff at the time and a few GM techs. They said they heat the bolt a few times to get the dissimilar metals to come apart, and or weld a nut on the end of the bolt in order to spin it out. Doesn't appear it's that tough to get them out. I didn't get around to it since I'd have had to taken over a decade old exhaust off and it didn't effect the truck. For less than a minute you'd hear very little noise that went away the moment the engine started to get some heat.

Right. Once the head breaks off all the pressure is gone. After that they will usually spin out. I was fortunate that I had some stud to grab on to. Bummer for the guys who have them break off flush with the head surface. That's when you have to do the nut weld trick.

So next step was to pull the balancer. None of the rods in the parts store "rent a tool" puller were long enough so I improvised. My old 1/4" Starrett dowel punch worked perfect!





Took longer to drive to AutoZone than to actually pull the balancer.



I need to Scotch Brite the surface up real good to make sure there isn't a super deep groove in the snout. I'm certain that was one of the oil leaks. I'm hoping it was just a due to a 17 year old seal though.

I also ordered the cam. Should have that before the weekend. Still trying to figure out what springs I need. Going back and forth between PAC 1215's and 1218's. The only difference being the seat pressure. The 1215's are 105lb at 1.800" and the 1218's are 130lb at 1.800". Open to suggestion from experience here...