Main Jet thread stripped

[barryadam]

I just changed out the main jet to a 165 as the PO had a 155 in there.  I felt the sickening feeling of the carb body threads give way at a really light torque and I'm guessing they are nearly stripped (2001 ? Go figure...).
1.) Has anyone else had this trouble?  Is this a common thing with Keihins?
2.) Is there an easy fix, or is it new carb body time?  I'm guessing the brass inserts are factory pressed and not really replaceable.
3.) Who the heck overtightens these things anyways?

Since I'm going riding at o'dark:30 tomorrow, I'll try some red locktite or epoxy and hopefully get a good seal as a temporary fix.  Who knows; maybe this was leaking a bit, causing some other problems.

Any comments?

B

[barryadam]

OK, so I took the carb off and apart to see the problem.  The brass insert is really the captured soft washer and the threads in the alum carb body are OK.
The jet, however is not.  It is new from Sudco, so it should be jen-u-wine Keihin.  On close examination, there is a small crack all around the second thread from the sealing taper.  So the jet had a defect in the material or thread cut and one more attempt at tightening would have resulted in the threaded portion shearing off in the carb body.  Popped in a 162 in the interim, after making sure it's threads looked OK.

Now I've seen everything. (almost).

B

[01KX5WOODSRIDER]

I have ordered main jets from Chaparral in the past and had the same problem with one size jet. Most of the jets I've got have been fine though. I guess a bad one slips through occasionally.

[dirtball]

I would try blue locktite first.  It stands a good chance of working well, and won't be nearly as permanent.  The red will ensure that its the last use of that
set of threads.

[barryadam]

Didn't need it.  I used another jet that wasn't cracked.