Help with GMS 47 engine adjustment

On 10/22/2003 7:05 PM Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:

It sounds like you are running out of fuel. I would check your fuel system from the tank to the engine (make sure there are no sharp bends, pieces of lint blocking the needle valve or clunk), and make sure your pressure line from the muffler to the tank is OK also. Several of the aftermarket mufflers do not provide adequate back pressure to the tank. I have a couple of Pitts mufflers I have had to block off one of the ports to get adequate pressure.

I don't have a filter inline with the clunk. I suppose its possible the needle might have some small debris caught in it. I'll check... By the way, I recently took my tank out and checked the clunck and fuel lines. All good. Haven't checked the internals to the needle however... Thanks

I had a similar problem with a big super tigre. It turned out to be debris in the spray bar! Once I cleared it out she ran like a charm. Also examine your high end needle carefully to be sure a burr hasn't developed on the end of it.

Try backing out the idle screw (make it richer). Set up the high end before the idle. Then after each idle adjustment, reset the high end again.

I had similar problems with my GMS 47. Turned out I was making adjustments in to large of increments. I think I started it at about

OK this is rediculous!!! I've tried everything... now I cant get the damn thing to run at all!!! it runs with glow starter attached only... that usually means it too rich on the low end! so I lean it out 1/8 of a turn at a time! then it won't start because its so damn lean its not getting any fuel... theres no in between! this is too hard.. it shouldn't be this hard there must be something else wrong!!! halp.. any ideas???

Have you tried another glow plug?

Just for giggles, change your glow plug again. You did do that first, didn't you? Stuff happens, and the "it runs with glow starter attached only" line sounds familiar.

Have you treid to get experienced help? Ther is definately something wrong and the fact that it used to run at low RPMS means something you did caused the current problem.

Try replacing the glow plug and running a small fiber through the spray bar (after you remove the throttle barrel. Also, try pressurizing the tank with the barrel removed and the main needle open about three turns. You dhould get a good stream of fuel through the spraybar. If not, then you still have a blockage in the carb. You DID rinse out the tank before installing it, right?

What type of glow plug are you using? I had a little trouble with my GMS 47 until I put an OS #8 plug in it. Has been running great ever since.

John VB

Those of you that recommended checking the glow plug... Thanks you much!!! I changed out the plug last night and put in a long, medium heat plug with an idle bar and after some needle tweeks it runs great... Man what a relief! I thought I was loosing my mind there for a while. No obvious visual problem with the old plug but that just goes to show you. Thanks again to all for your help...