I'm finally trying to break in my new HPI .25 engine. when I start it to get thru the first tank wheels off the ground no radio no receiver on. it goes from normal idle to what seems like Wide open throttle or close to it after about 20 or 30 seconds and I have to shut it down so I dont wreck a brand new engine.. not sure what to do at this point, never had the problem with the .21. Any help would be appreciated. thanks.
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New engine goes WOT in idle
- Thread starter grunt0420
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El Pirata
RCTalk VIP
Turn the transmitter on and the receiver on before you start your engine, ALWAYS! Bet that helps a great deal.
El Pirata
RCTalk VIP
Stupid question, is the throttle linkage hooked up to the carb?
Well, a motor needs air and fuel to run.
It obviously has more than enough fuel.
If the carb is at idle position, and it's revving, it must be getting air from somewhere other than the carb entrance.
I would assume it would be drawing air a pin hole in the fuel line, or where it attaches to the carb, fuel filter, or tank. Sometimes the niplles on the tanks can leak, and be hard to track down.
It is also possible that the O rings on your needles are bad, allowing air to shoot down the neck of the screws.
It obviously has more than enough fuel.
If the carb is at idle position, and it's revving, it must be getting air from somewhere other than the carb entrance.
I would assume it would be drawing air a pin hole in the fuel line, or where it attaches to the carb, fuel filter, or tank. Sometimes the niplles on the tanks can leak, and be hard to track down.
It is also possible that the O rings on your needles are bad, allowing air to shoot down the neck of the screws.
kwong2001
Hardcore RCTalk User
You may have the servo reversed.
Maxxcrazy88
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Did you check the backplate???? it's s problem area on Tha s-25 check it and tighnten if necessary... sounds like you have an airleak and that seems the most probable place it is...
- Thread starter
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Actually all is well, went down to the lhs , we also thought it might be an air leak problem so we took out the fuel filter and replaced the fuel line to the carb, but it was still doing it. I already knew the backplate was sealed right. It turns out the low speed needle was lean at the factory setting and we had to richen it up a bit. Finally was able to get thru the first tank.