TK5310
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- RC Driving Style
Last few outings I've had a wierd issue come up with my picco .28:
As it comes back to idle it leans out, gets that high lean idle thing happening, but after a few seconds it settles down to it's normal idle, blipping the throttle also settles it.
At normal idle it is not lean, nor is it lean anywhere else in the rev range - it tunes fine & reacts normally to tune changes.
It's not running hot.
An air leak would normally cause a lean idle, but would not clear up after a few seconds or a throttle blip.
Lean HSN would have it running hot.
I've tried to tune it out, but I can richen up the LSN untill it stumbles when you hit the throttle, I can richen up the HSN untill it flat in the top end & the issue stays the same.
I thought it was due to a missing baffle in the fuel tank allowing it to suck air under brakes, but I've replaced the tank & it does it with both full & near empty tank.
I've replaced the pipe seals & fuel tank with no change.
From here I'll replace the fuel lines & look over the carb for leaks - but I'm not holding out much hope there is any problems there.
Motor is getting on a bit, over 10 gallons on it, but still has a little mechanical pinch & enough compression that it can't be turned over by hand.
It'll idle almost indefinately & still makes very good power - I've had it at a low idle for up to 5 minutes without it stalling, which tends to indicate that the motor is fine.
Motor has been sealed - but a long time ago.
Just not sure where to look next!
As it comes back to idle it leans out, gets that high lean idle thing happening, but after a few seconds it settles down to it's normal idle, blipping the throttle also settles it.
At normal idle it is not lean, nor is it lean anywhere else in the rev range - it tunes fine & reacts normally to tune changes.
It's not running hot.
An air leak would normally cause a lean idle, but would not clear up after a few seconds or a throttle blip.
Lean HSN would have it running hot.
I've tried to tune it out, but I can richen up the LSN untill it stumbles when you hit the throttle, I can richen up the HSN untill it flat in the top end & the issue stays the same.
I thought it was due to a missing baffle in the fuel tank allowing it to suck air under brakes, but I've replaced the tank & it does it with both full & near empty tank.
I've replaced the pipe seals & fuel tank with no change.
From here I'll replace the fuel lines & look over the carb for leaks - but I'm not holding out much hope there is any problems there.
Motor is getting on a bit, over 10 gallons on it, but still has a little mechanical pinch & enough compression that it can't be turned over by hand.
It'll idle almost indefinately & still makes very good power - I've had it at a low idle for up to 5 minutes without it stalling, which tends to indicate that the motor is fine.
Motor has been sealed - but a long time ago.
Just not sure where to look next!