My reason for writing this is the fact that in all the how to articles that Ihave read, they tend to go lightly on the parts prep for reassembly. many of them use new parts like heads and stuff where things are outof the box clean. When you have to do a tear down because of something like a gasket leakyou need to use the old parts and dirt and debris becomes public enemy number one.

Welp, have all the gaskets and ARP head bolts on order, got my heads back from the shop and will be making the LBD whole again. Some things that I noticed and a lot of good information I picked up along the way.

With a rash of stripped bolt problems I seen here and the one header bolt that was stripped on my heads a while back by a shop.

1. Cleaning the block decks I used a plastic scraper and a nonmetalic scrub pad with some of that purple degreaser. Get it all! BE CAREFUL light handed and don't dig! Do NOT use a metal scraper. I packed every hole and opening including the bores with paper towels or rags to keep the debris to a minimum.

2. When you pull the heads a lot of coolant goes into the bolt holes. You must absolutely get that all out. They need to be clean and dry. the twisted paper towel works good. Trying to use an air gun even with a rag just blows coolant everywhere.

3. I took an old head bolt and ran it down each hole by hand. Bingo, I don't know what they used at the plant, but there is some sort of goop or thread locker in those holes. I took two old head bolts and shaved them on two sides (not my idea got it here on the forum) and then used a thread file to clean them up and used them with a bit of brake clean to chase down each hole. Wow! I did not want to use a thread chase as they have a tendency to cut like a tap. I wanted to clean not cut. worked great!

3. Header bolt holes where just as bad. So I did the same thing with those. I filled each hole with brake clean, then ran the shaved bolt in and out several times.

The heads were cleaned and trued up only. (Stock LS1, no porting)

I took my torque wrench in for calibration! A definate must do!

Pick up a set of GM manuals and use their torque spects to the letter of the law. Unless you are using something Like the ARP bolts and then follow their laws!

 

I would also suggest taping the head bolt holes. If you have the ability, measure the threads on the ARP bolts vs the stockers. Theres a differance. Just try threading an ARP in by hand, it won't go.

Hope this helps.

Mike V

 

Hum, Going to have to check that out, Bolts won't be in until tomorrow. Funny I either missed it if it was posted in the past, or nobody mentioned it???? This was sort the reason I posted this. a lot of little trade secrets that can save people a bunch of grief. I am a little concerned on the taping though, Aluminum is bad enough, I don't want to narrow down the thread root any more or at all for that fact.

 

Got my ARPs I was able to screw them in by hand with the oil that was on them out of the box. They are a lot tighter than the stockers I took out and used to clean the threads. They were not so tight that I would consider a thread tap, with ARP lube or motor oil they will go in a lot smoother. They are very consistant all the way down! I could feel the entire thread groove being used, there was NO slop.

The Jury is back and the verdict is don't tap the threads, and the directions from ARP specifically state Clean and do not tap.

 

I should have said chase not tap. Did you measure the differance in OD?

Mike V

 

No, but I can mic. them tonight when I get home, just for grins

 

Just what are the torque specs for the header bolts?

 

My tip on head bolt holes: Use a shop vac, take some rubber tubing and step it down to a size that fits inside the bolt hole (I had to step down with 3 or 4 tubes!) and then suck out all the liquid. I tried rolling up paper towel (Scott shop towel) but it would just get stuck in the hole and wasn't sucking out the bottom of the holes. Shop vac worked really good! Clean all your parts thoroughly before putting back together.

Remember P6 "proper preparation prevents **** poor performance!)