I originally installed the heads on my new engine (new ZZ4 shortblock) using the GM Performance 12495499 bolt set that comes with thread sealant on the bolt threads and torqued to 65 ft/lbs in increments. I added a bit of Permatex High Temperature Thread Sealant to each bolt for extra insurance (or so I thought). After I had finished torquing down all bolts, I noticed that the #1 bolt (in the middle of the head) was pressing down on the valve spring locators near it because the head of the bolt was too wide.

So what I did to fix this is that I bought the ARP head bolt kit with separate washers and used a dremel tool to grind down two sides of a washer to clear the spring locators. I took out the old GM bolts one at a time and put in an ARP bolt in its place (at 70 ft/lbs torque since thats what the bolt kit instructions stated) with a bit of Permatex sealant. (Except the top 4 holes, which I used ARP Lube on, since they are blind holes on my ZZ4 block).

Will not cleaning the block bolt hole threads after removing the GM bolts cause leaks later on?

I figure the block still had some of the GM sealant on the threads in addition to some of the Permatex sealant I added originally. Since I was going to be adding the same sealant with the new ARP bolts, I didnt bother to clean the threads in order to avoid having to buy new head gaskets.

 

IMO you should be alright, just torque the new ones down and get on with the project.

 

It is good to clean the holes and threads but I bet you will be just fine.

 

if you weren't kicking around a bunch of dirt and such then i wouldn't worry. did that on an old motor i rebuilt and its running just fine. actually just took a look at it the other day

its good your taking this much care though