Beginner Help: Trying to break in but engine is overheating

[thepat]

Hi,

I bought an HPI Nitro Monster King RTR with a T-15L new a while ago. I am trying to break the engine in but it seems to be overheating no matter what I do.

I've been running the engine at idle and using a Venom Smart Temp to monitor the temp, the engine quickly climbs above above 250. The factory setting on the High Speed needle is to be flush and I've already backed it out several mm and it seems to make no difference. It managed to climb to 290 before I caught it and shut it down. Additionally, when it gets above 230, the engine appears to increase revs without any input from the throttle.

No matter how much I back out the HSN, it still appears to run lean and I am not getting much smoke out of the exhaust.

I am completely new to nitro RC and while I've been following the instruction manual included, I feel I'm missing something. Any help would be greatly appreciated. Thanks,

Patrick

 

[dub c]

its in the low side. richen the low side after you reset the high needle.

 

[Huggybear87]

I find this very helpful when trying to tune.
https://www.rcnitrotalk.com/forum/showthread.php?t=60832#flowchart

 

[Extreme RC Mods]

Your adjusting the wrong needle as the HSN has no effect on the idle or low rpm tuning. Richen up the LSN which is on the side of the carb where the linkage hooks up and the temps should come down.

 

[bgbdwlf2500]

Seal the engine if you haven't already

 

[olds97_lss]

Your adjusting the wrong needle as the HSN has no effect on the idle or low rpm tuning.

Not 100% true, but not far off. A HSN complete screwed in shuts off the fuel completely to the engine. Have had that happen to me before when an o-ring dried out and the HSN was screwing itself in. lol

Does the manual say anything about where to set the LSN?

 

[thepat]

Thanks for your suggestions, I will try to mess with the LSN.

Strangely the manual barely mentions the LSN and does not mention it when it comes to temps.

 

[olds97_lss]

Typically, the LSN flush with the throttle ball piece is fairly rich.

On a traxxas 3.3/2.5, they say to have the screw flush with the slider end vs the ball end housing piece:

To be safe, set yours flush with the outer housing instead and go from there.

I couldn't find the manual for a t-15L, but I found one for the T-15 and it says to set the LSN flush with the housing as the factory setting. They don't tell you as much as show you a photo of it flush.

From T-15 manual:
HSN

The wording for the HSN isn't real clear either, but they say to not turn it in more than 1/2 turn to lean it out (total 2.5 turns from flush would suggest 2 turns from flush is factory).

LSN (photo shows flush with carb housing. Didn't realize your LSN was on the carb housing vs the throttle barrel):