sylo26

Hi guys ! My motor , when he's coming hot after 2 min just drop his speed slowly and kill an never start again ; just start after he's cold . I tried to ajust needles and nothing change . I would like to know if it could be the ignition system . I use a 2100 nimh battery . What do you think about that ? Thanks ! Paul

scale only 4 me

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Paul,,
there are so many variables,
Make sure there are no air leaks
Is the air flow over the engine good?
What gas/oil ratio are you running?

2100 battery is fine and way more than you need

You should post this question here too http://www.rcuniverse.com/forum/foru...smode_1/tt.htm

jetmech05

Does it smell hot?
If you have good airflow, then it's either the mixture (gas to air ratio) or the fuel/oil mixture. Most of the guys I fly with break in on an ashless oil at 32:1 for a couple of gallons, then switch to a good synthetic like Redline or Royal Purple at 40:1. I know some oils say you can run as high as 100:1....but given the choice I'll save my motors and run at 40:1.
For airflow you must have an exit for air on your cowling....they say the exit is supposed to be 3 times the entrance area...I break that rule alot.....I run maybe 2 depending on the model.....
Airflow is like water it will take the path of least resistance so you need an open area in front of the cylinder and an exit aft of the cylinder.....If the exit is too small then airflow will dam up forming positive pressure letting no more air in and then will heat up as well.
Good airflow may require you to damn up an entrance into the cowl to force air over the cylinder...
Good Luck

jetmech05

sorry duplicate post

sylo26

Thanks for responses guys . I trie with no cowling and its the same . But maybe it could be my mixture . I started to use synthetic oil after 2 gallons of mineral oil and I put 3.5 onces in one gallon of gaz, is it good ? Thanks ! Paul

jetmech05

That's a fuel/oil mix of 36.5 to 1 which is good....with no cowling...it has to be the fuel air mixture....you're too lean..if that's not that then there is something wrong with a bearing.

sylo26

Yes , I change my gas line to be sure don't have air in it , tried differents needles ajustment , and no result . I think I'll have to cheak the bearings . Thanks ! Paul