.25 engine problem

I have been running a GMS BB .25 for several months with no problems. All of sudden it runs out of gas in a vertical climb. I have pulled the tank, changed the fuel and exhaust lines, checked all the bolts on the engine for torque and yet it still dies in a climb on a full or half empty tank. I have tried richening the hi speed jet and that does no good at all. I even richened up the low speed side and same result. Anyone have any ideas?

Reply to
Watchur6
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Change the tubing in the tank, both the brass and the silicone fuel line. Blow out the fuel inlet/spraybar with air. Buy a good engine. :) Dr.1 Driver "There's a Hun in the sun!"

Reply to
Dr1Driver

Buy a good engine? What a lame response. Are you saying that an OS, Enya, YS or any other engine that develops a sudden problem is not a good engine?

There are a couple of likely problems:

The fuel line inside the tank has a small split where it joins the brass tube.

A small piece of junk has made its way into the carb and is preventing full fuel flow. Can you adjust the engine very rich on the ground? If not, then I suspect this is the problem.

Something blocking the muffler nipple inside the muffler.

Reply to
Paul McIntosh

You have an air leak somewhere, and you've only checked about half the places it could be.

Reply to
Mathew Kirsch

That's the most likely thing, Matt. I've had good performance from GMS engines, but they have a common Achilles heel with every brand of engine I've seen from PRC: O-rings. Apparently good quality O-rings are just not to be had in China.

Watchur6 - check for splits in those on the needle valves, base of carb, and backplate. Odds are good you'll get to the root of the problem.

Abel

Reply to
Abel Pranger

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