Petcock problem, I think

Got a 82 xj650 maxim, was sitting over the winter, got it fired up and seems to run on prime but will eventually die out when left on Reserve. Haven't tried the ON position yet.
Any suggestions

Thanks

 

Petcock problem or simply a vacuum line problem; check the smaller (vacuum) line for cracks, etc.

If you replace it be sure you use vacuum line.

Might need to rebuild the petcock: http://xjbikes.com/Forums/viewtopic/t=25058.html

 

agreed, here's a quick test. If you can get the vacume line off the manifold boot, put it in On or Res position, expose the fuel Outlet, and put the vacume line to your mouth and suck. You should see a very generous flow of fuel come out. If you have more than a 1/4 tank of fuel you can put it to On. Leave the Reserve setting for when you're out of gas and not near a gas station

 

Thanks, I'll give that a try.

Dave