Carter01

iTrader: (11)

Found out today that after recently taking my SLP 25% underdrive pulley off that the previous person that installed it stripped the crank bolt. What are my options besides pulling the motor and replacing the crank? My thoughts go as follows. 1. Try to retap the crank and use a standard SAE bolt .
2. Maybe use a Heli-coil (spelling) to fix the issue.

Please let me know your thoughts and if this has happened to anyone and what you did that was a successful and long term fix to the problem.
Thanks,
Andy

sroach20

iTrader: (31)

pin it!!

SSANIMAL

iTrader: (10)

I Had This Problem Last Week On My Car I Used A M16*2 Tap Bolt And Used A Arp Bolt And Fixed The Problem Try That If That Does Not Work Use A Helicoil.

vettenuts

iTrader: (4)

I would try the correct tap first, see if that takes care of the threads. If not, heli-coil of the same thread. I would also pin the pulley. Use an ARP bolt, it is installed with ARP Assembly Lube so there will be less chance of issues with the Heli-coil.

98Camarod

iTrader: (43)

Ive been there my friend. I'd try and tap it first with the 16mm 2.0 tap. If you cant get it started by hand, tap it lightly and turn it at the same time. This is how mine was fixed. If that doesn't work then you should helicoil it.

NSTY WS6

iTrader: (5)

Friend of mine had that happen on his 306. After talking to several places, he decided to put a stud in the crank. There should still be threads behind where it was stripped. They re-tapped the threads with the stock size tap, and found a stud to fit with a nut and washer. The stud is cut off about .5" past the nut, so he is still able to use a puller....

eallanboggs

iTrader: (1)

If some threads(deeper ones) have not been damaged the stud(threaded rod) is a good idea. You want to get as much penetration as possible by the stud for the best possible purchase on the undamaged threads. Remember that this is an interference fit so you don't really need to pin or key the crank unless you plan to go F/I. The stud will have to be cut long enough to ensure that sufficient threads are expose when the pulley is put in place to get a large flat washer and 16mmX2mm nut started on it. You're not going to locktite this stud in place because you may have to remove the pulley again sometime in the future. Be sure the the pulley is square and plumb to the crank before you begin to apply the pressure to bring it home. There is a STEP on the bore of the pulley where it abuts to the crank during installation. This step is there to help you to get the pulley started onto the crank straight so use the STEP for this purpose.

silverLSWON

iTrader: (16)

def try a tap first!!! best of luck to you

618HAWK

iTrader: (361)

If needed I have a been also making a tap with a drive extension that will let you get the tap inside of the crank, to clean out the threads. I would think you would have a good chance with a tap if you were able to get the old bolt out.

Shoot me a pm if interested.

Here is a previous thread with the same problem if it helps.

https://ls1tech.com/forums/showthrea...t=#post7631964

Also have another batch of install tools ready if intrested to prevent any further damage.
https://ls1tech.com/forums/removed-locked-thread-graveyard/391883-new-crank-dampener-installation-tool-pics.html

Carter01

iTrader: (11)

Thanks again for the help. Only problem now is finding a tap that size in my little town. Everyone that I have talked to only carries 12mm. Anyway, thanks again!
Andy

Carter01

iTrader: (11)

Tried the 16mmx2.0 tap today and it worked great. Also installed a new crank bolt and the pulley tightened down just fine.

Thanks again for the help!

98Camarod

iTrader: (43)

Glad to hear that you got it sorted out.

guessohw

I know this is an old post, but by chance do you still have something of this nature for the crank?