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Symptoms of an air leak?

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Alright. Over lunch, re-installed the engine and took her out for a run. Took a few to get her tuned to at least run. Her idle seems a bit rough still but its much steadier than before. Temps stayed under 300 except for one instance. She cuts out if I give her full throttle straight from idle but I think thats normal? (correct me if I'm wrong)

Think I'm gonna go out to the track later this week and see if I can get her tuned better and see if the problem is for sure gone.
 
If it's tuned right and warmed up and hasn't been sitting at idle for more than 10-15 seconds, you should be able to hammer to WOT and it should go without much hesitation. After it sits and idles 15 seconds or longer, they tend to load up a bit and get worse the longer it sits. Then it will blubber and stammer until it gets the crank case cleared out, then go fine.

If your hitting 300 and it's hesitating as you suggest, it really does sound lean. Especially if it's the slayer... it has smaller/lighter tires than the revo which means throttle response should be almost instant with very little lag ever. Also means you should be running much closer to 200F. Unless you have it geared to the moon for top speed only.

If you can't get it to run cool on pavement when not running WOT for extended periods of time, then your probably not going to get it to run any better off road.

Just had a thought, are you running with the body on or off? If on, do you have a decent hole in the windshield to give it good air flow?
 
I didnt get a chance to go to the track last night. So can't say much on its performance with further tuning.

However, all this has been done with the body off. Personally, I think it would still run cooler with the body on simply because I'm playing with it out in the midday sun here in Iraq. Shade makes everything cooler here. Thats also why I want to wait until evening and I can go to the track. Its cooler at night and no sun so I dont have to worry about inflated temps because the sun is beaming down on the metal.

And its still doing much better now than it was before the sealing. I'm just mainly watching for blue smoke and getting it to run right and have a good idle. Just taking note of the temp, not tuning by temp. The one time it did reach 300 was after two or three long WOT runs. I guess I kinda failed to mention that? Also I run stock pinion and 40T spur. I'm trying to tame the speed and get more acceleration. Theres only one long stretch on the track I run :)
 
Do you use an ez-start? A quick way to shed some weight and get better air flow around the engine is to ditch the ez-start and get a pull-start. If it's tuned right, a few pulls is all it takes to get it running.

Didn't notice the "in iraq" under your avatar... I guess when you start at 110F, there's a high likelihood you will run a bit hotter than someone who runs in 80F. 140-150F over ambient is usually what to shoot for. So, 300F is still a bit high, but maybe not for a TRX. Although, at those temps, your not doing your internal components any good.
 
Yeah I use an E-Z Start. Wanna keep it for now. As for the internal components, I aint worried. When I get back to the states its going to get a new motor more than likely.
 
Didn't notice the "in iraq" under your avatar... I guess when you start at 110F, there's a high likelihood you will run a bit hotter than someone who runs in 80F. 140-150F over ambient is usually what to shoot for.

LOL, 110F, yeah at like 7am. Some of my hottest days over there were more like 136-140F. Usually around 110F-125 though.
 
I tell ya, I doubt it's a main bearing simply because you have such little fuel through it. My suggestion is to seal the backplate, carb throat and exhaust opening with the RTV and see what happens. The fuel residue you are seeing may be as a result of a leak where the pipe mounts to the engine. I've had it happen to be before as well.

Does the pipe mount to your engine with screws or springs?
What if it had springs how would you seal it?
 
What if it had springs how would you seal it?
Personally I wouldnt worry about the exhaust port. I use copper permatex RTV to seal the backplate & carb throat. Then I take Associated's Green Slime and put a dab around the threads of the HSN, LSN, and idle screw. Just my :2cents:
 
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