99ssleeper

iTrader: (98)

Ok, I pulled a cam today.

Last time when I pulled the balancer off, I put a 6" long 3/8" extension in the hole of the crank, then pressed the puller against that so there would be no pressure on the threads. The 3/8" extension slides all the way in and bottoms out in the crank bolt hole.

Well this time I used a 1/2" extension without thinking. The problem is the 1/2" extension does not fit all the way into the crank bolt hole and presses against the threads. It is too big to slide through the threaded part to bottom out in the hole. Well, dumb *** me thinks it is bottomed out like the 3/8" extension did, and I proceed to pull the balancer.

Well, I must have deformed the threads in the crank from the pressure of the extension pushing in on them from the pully puller tool, because now I can only thread the bolt in a few turns and it stops. However, I believe the problem is only on the first few threads.

What can I do to fix this? Can I get a tap somewhere that will work?

Also, I forgot the bolt size...is it M20? What is the pitch?

ANY help is appreciated....this pisses me off

I cant just force a bolt in there because the crank is hardened and the bolt is not...it will just chew the bolt up. I dont want to have to pull the engine...

What can I do???

Cal

iTrader: (1)

You should be able to clean it up with the proper tap, no need to pull the engine for that. Sorry I don't know the size, but you can get the tap from an industrial machine supply.

1999_SS_M6

the thread pitch is a Metric 2.0 You'll probably have a hard time finding a tap larger than a 1.75 though. Good luck man.

JoeyGC5

iTrader: (24)

"This method has been used before and isn't exactly recommended"

I've seen people take the factory crank bolt, make a cut through the center with a bandsaw/hacksaw. Then file the cut edges to for a outward facing V. Then they'll slowly use this bolt as a tap, with plenty of cutting oil/motor oil and the threads will clean up.

99ssleeper

iTrader: (98)

I thought about using the bolt as a tap by doing what you said, but I'd have to find a hardened bolt for that...

I know most taps aren't more than a few inches long, so I am kind of stumped...

dropkick

I have used this method on other applications and it will work. You can make a "thread chaser" as described. Even though the crank is hardened, you won't actually be cutting any material, just cleaning the burrs off the threads. Just take it easy and use a lot of oil. Run the chaser in a couple of turns, then back it out and clean any burrs off. Repeat this process until the threads are clean. Good Luck and let us know how it goes.

99ssleeper

iTrader: (98)

I tried what JoeyGC5 and dropkick mentioned. It seemed to work well. I can get the GM bolt in until the head touched the crank snout now.

I am still going to try and get a tap just so I can chase the threads...maybe I'll order that ARP balancer bolt now

Thanks everyone!