I have run about 3 gal fuel through my 4 stroke .91 Thunder Tiger engine. It starts good, runs good for 4 min 20 seconds and quits. within a few seconds each time. And yes it has plenty of fuel. If it is restarted without refueling, it runs another 4 min 20 seconds regardless of mixture setting. Not dependable enough to fly.

Any thoughts??

Don

I have one. Mine was unreliable also. I did find a tank problem that was causing some of my problems. Additionally, I did find that running high nitro content fuels did cause some overheating, so I ran 5% fuel with 20% oil. This did seam to help. I think your problems are heat related. I might add that when, my engine was running well, it made great power. The .91's little brother the TT .53 FS is a great engine and very popular overseas. Remember, overseas nitro is very expensive, so they run FAI fuels with no nitro. You might try it.

I have a webra 1.20 that has a simular problem. I have tried different things (changing fuel, glow plugs, tunning, etc.) I finally gave up on my engine and replaced it with a satio 1.80 (A REAL ENGINE). I would say take the motor off of the plane and run it on a test stand with a different tank to isolate any tank problems, if you still have the problem you may want to check the bearings in the motor and make sure they arnt bad (I know its new but you never can tell). I dont know much about thunder tiger 4 strokes ( I only run saito and YS) but I always run mine with morgan fuels 15% synthetic fuel. Just some suggestions...