Air Leak, I think

[Tarant]

I think I have a air leak but am not sure.
First off it was hard to start and after I got it to start it was running ok, but it was rich are running slow so i leaned it out abit and no change, so after about 15 min, I had the HSN leaned 2 full turns in and teh temps hit really high, so I richend the hsn and the temps were around 240 so I richend it out a bit and no temp change. and sometimes the engine would rev high enough to make my savvy creep when in neutral, and other times it would rev very low as if it were going to stall.

I hope it is just a airleak cause if it isnt I am screwd

 

[RatzoRC]

Well, it wouldn't hurt to take off the back plate and seal it up.
Do the carb as well.
Check all your fuel lines, and fuel tank for cracks or pinholes.
Check the fuel cap on the tank, and make sure it has a tight seal.
If you have a primer tank, they have been suspect on HPI's
Check all youe screws on your engine.
Last, check the carb boot on the slide for holes or tears.

Good luck.

 

[Candyman]

Not sure what engine you're running, but I had similar behavior out of my K4.6 that I just built. I sealed the backplate, carb and HSN fittings with Ultra-Copper and it seems to be running more stable. I was getting wicked temp fluctuations and the engine seemed to either be bogging or running over 300. Now I think it's found it's comfort zone.

 

[Tarant]

I have the s25, and i have had the same problems as you Candyman, one minute I was smoking the next I was at 210. Well I am going to seal it up and I am hoping it works.