I recently ordered the petcock valve kit, hoping this might help if the petcock is leaking fuel into the cylinders causing my flooding problems. Then I read in a Haynes manual that the only way to fix this problem is to buy a whole new petcock assembly. Anyone know if this is correct?

Normally I would say buying a new petcock is poppycock, except I just went through this on my 85 XJ700X. I had a terible time with the carbs over the last couple of years as everytime I would start it fresh in the spring the carbs would be totally gunked out. To make a long story short - the petcock was slowly leaking at the O-Ring seal and as the gas in the carbs would evaporate the petcock would refill the carbs. This would happen all winter long and by spring I would have to pull the carb rack and clean hard residue out of everything. If you have ever pulled the carb rack on a XJ-X you know my frustration.....

I bought a rebuild kit for the petcock and installed it, and it still leaked. Turns out the potmetal casting was warped or not made right to begin with, and the seat was too far down in the casting for the O-Ring to seal properly. The intermediate block between the 2 diaphrams limits the travel and is the "stop", and even pushing on it by hand would not get a seal.

I am a fairly handy tech and was able to cut the old seat out and install a brass insert and cut a new seat on that to make it seal, but it was a PITA and I would still like to find a good stock petcock that was not messed up to replace this one. (If anyone has a good X petcock for sale please let me know).

All that leads us to this- if you can find a new petcock then buy it. If you can't then put your kit in and test it to make sure it is not seeping. If it is seeping, and your floats seal, then it will be fine all season, but drain the tank completely when you put it up for the winter.

Youi have to take in concideration 1: How many miles is on it. 2: How old is it. I have a 82 XJ110 I just took mine apart cleaned them put them back to gether and no leaks. I used a little vasaline to make sure the seals didn't break or move out of place. Then again my XJ was garage kept and only had 9700 miles on it when I bought it. If the bike has been weathered or high millage, your better off getting new ones.