K5.9 tuning problems - video

[zigro]

I'm trying to tune my new K5.9 after breaking it in. HSN is 7/8 lean or almost 1 full turn lean & Idle is 1/2 turn in from factory. I know all engines are different, but what are the average needle settings most people use? I'm running 30% fuel with cold R5 plugs.

Here is a video of it running...

Please tell me what tuning adjustments to make. Any comments help, thanks.

 

[Mickey]

that sounds like it has an air leak to me. definitely lean on the mid to high. How many tanks of fuel through the motor now?

this thread helped me a lot when i was learning to tune my motors.
https://www.hpisavageforum.com/threads/performance-tuning-let-the-engine-tell-you.8295/

 

[maximusraylius]

think mickeys right ... might be a air leak ... but deffinately a tad to lean on the hsn ... turn it back out bout a 1/16 to 1/8 turn n see if that helps it from dying on you ... lsn is loading up to it looks like ... has tons of smoke on take off ... can lean the lsn a tad more...but very small turns on it and as you turn the lsn in it will want to rev a lil higher on idle so might need to adjust that accordingly as well .... but start with the hsn first ...

 

[zigro]

How do I test for an air leak & how do I seal it if there is one?
Thanks guys.

 

[Mickey]

pull the motor from the truck. using a fuel tube and plugging both the carb and exhaust port, blow into the fuel tube and check for leaks by spraying lightly soaped water over the motor. pay particular attention to any places 2 surfaces meet.

as for sealing it up take the piece that is leaking off and use a very small amount of rtv sealant (gasket maker) and reinstall part.

note:: if you have to remove the backing plate make sure the piston is at top dead center or the piston will be damaged by the removal of the backing plate

 

[IamSavage]

that is the same problem i had what every i did it cut out and run so bad one min it would be ok then it would cut out so i richend it up and it would then run still like s**t and i found it was the half tank prblem so i pulled out the old tank and put in a xtm buggy tank its only 125cc but i have never looked back and it been now about a month and she is a sweet runner

 

[mathew byford]

Hi i think I'm having the same problem the engine revs on its own n keeps cutting out. Any ideas

 

[Jam Racing 1]

https://www.hpisavageforum.com/threads/list-of-useful-nitro-engine-threads.13941/

 

[mathew byford]

Cheers thanks for the help. Also any ideas why the keeps revin high peaking them dropping down (air leak)

 

[Jam Racing 1]

Is possibly the air leak you are thinking of, also could be related to the tune of the engine, if ya have it out already then now is a good time to seal it up, and then reset the baseline needle settings and fire it up again,

 

[robn69]

Nitro RC Engine Tuning Guide and Diagnostics: By …:

This Video helped me a lot when first tuning my truck. But if you have air leak guess It's not going to help much.

 

[mathew byford]

Is possibly the air leak you are thinking of, also could be related to the tune of the engine, if ya have it out already then now is a good time to seal it up, and then reset the baseline needle settings and fire it up again,

Cheers thanks for the help I'm hopfuly checkin tonite