Trouble Starting after refuel

[CJ-FOREVER]

I have the XTM Mammoth with the XTM 24.7 in it. When the 24.7 is cool it will start right up on the 3 pull. But after running a tank through it and fill it up it will not start.
I changed plugs, and still nothing. I am running Blue thunder 20% fuel. I am wondering if I am running it to lean? At WOT there is plenty of smoke coming from the pipe. So I dont know. What do you guys think?

 

[AC48]

Engines are just sometimes harder to start when the are hot. After a run I can't start my 12R SS for like 5 minutes. But after i run my savage i can start it right back up after a run. Just depends on the engine i guess.

 

[mattyk6]

How is the pinch? Try rotating the flywheel by hand. Is there still significant pressure to turn it over? How about when the motor is up to running temp? If a motor is hard to start when hot (or warm), it could be because the engine needs to be rebuilt or pinched.

Also, how did the motor turn off? If the motor ran out of fuel, you would need to re-prime it. Also, depending on how you shut off the motor, you could have flooded the motor. I usually try to shut off the motor by pressing my thumb to the flywheel (only at idle though). I've also used my frequency clothespin.

Matt

 

[CJ-FOREVER]

It is only 2 weeks maybe 3 weeks old. Lot of pressure in it. The motor turns over with no problem, just wont start when it is hot. Only has about 8 or 9 tanks throught it.

 

[RandyT]

Alot of times, it's because the carb is hot, and the fuel cooks off before reaching the cylinder. As long as your running at correct temps and tuning, you can always just refuel prior to running it dry. Good luck.

 

[AC48]

RandyT, I agree. I don't think there is any problem...just either needs to cool a little or you can just fuel up while it is running. Having a composite carb body makes it easier to start when hot because it isolates the heat from the fuel so it won't cook before it reaches the cylinder. That is why the S-25 has that kind of carb, which is why i can start my savage right after a run and not my 12R SS.

 

[CJ-FOREVER]

Is there a way to fix this?

 

[SkyMaxx]

Run a little richer.

Verify your engine temps with a temp gun to make certain they are indeed in limits.

Do not let the tank run dry prior to refueling.

Make certain you have a solid charge or new batteries in your glo-ignitor.

Aside from that and the thoughts posted above, allow the engine to cool down and then give it a go. If you have more than one RC, try running the other RC between tanks. Then you get to play with all of your toys and the engines get to cool down a little between runs.

 

[X_Gamer7]

You could try a different carburator, nylon ones are very nice and will prevent vaporlock (as described by randyT). I would say just to listen to everyone else though, and refuel it before it runs out of gas. Unless you must run it until it is out of gas, or just like the fact that you dont have to watch the gas so that it doesn't run out, i wouldnt get a new carb tho.
l8r

 

[olds97_lss]

I have the same problems with most engines I've ran. To avoid it, one an engine is broken in, keep an eye on the fuel level. When it gets down to 1/4 tank, refuel before it dies.

Get a temp gun. Most engines don't boil fuel when they are around 200 but more when they are over 250. If your over 250, you may be a bit on the lean side.

Which would make it run hot and be hard to start until it cools.