Why does my T-Maxx keep dying? I'm extremely frustrated right now.

[JayJ]

I'm going to cut right to the chase on this one. I bought a T-Maxx yesterday (my first experience with nitro) and I intended to break the engine in today, but it dies almost immediately after releasing the EZ-Start button. After messing with this stupid truck virtually nonstop for the past six hours and after visiting my local hobby shop three times, this is what I know:

1. The engine is not flooded.
2. All connections (electrical and fuel line) are secure; no leaks.
3. All three glow plugs (I bought two extras) are good. They were tested by removing them and grounding them to the cylinder head, and also by a special tool that they had at the R/C store.
4. The blue wire that connects to the glow plug is not shorting out or arching; it is completely covered with thick fuel tubing, which was installed during one of my "sessions" at the store. This made an improvement, but did not solve the problem.
5. I'm using Traxxas fuel
6. The high-speed mixture screw is set according to the manual (backed off 2 1/2 turns), but I've tried it in 1/16 inch increments everywhere from 1 1/2 to 3 turns out; this made very little difference in how long the truck would idle before dying.

I've followed the steps in the manual to the letter a dozen times, and I've done everything suggested to me by my hobby store and then some. I also tried everything that I found in the FAQ on Traxxas' web page concerning "Why won't my engine start?" They made no difference. The instructions that came with the truck are useless concerning this problem; they don't even address it. They assume everything goes just peachy. I am completely baffled. Add to this the fact that three of my shocks were not assembled well and leaked oil everywhere, which of course I already wasted time fixing (good thing I had extra shock oil on hand), and that just makes things that much worse. I am sure this truck is a total blast when working properly, but as of now, I must say that I am not at all happy with this T-Maxx. I did not spend $450 to put up with this kind of seemingly needless trouble, and I just can't relate to Traxxas' supposedly "beginner" or "user friendly" reputation right now. I'm going back to the hobby shop tomorrow to see if they can pull a rabbit out of a hat for me, but I would still be extremely grateful for any other suggestions. To say the least, I have not enjoyed my day off work (when I was looking forward to having fun driving my new monster truck all day), but it hasn't been a total loss. I did get the body painted! Whoop-dee-doo! Sorry if this post sounds a little harsh, or like I'm overreacting, but I just had to rant a little bit there. Anyone have any suggestions?

[Apache]

Welcome to the world of nitro R/C! New engines can be finicky, but it sounds like you problem might not be the engine, but possibly fuel related.

First thing is to look into the carb with your radio and receiver "on" and throttle at idle and see if the barrel is open at all. Then turn your throttle trim clockwise to see if it opens any more. It should open a good amount as you're turning it. If it was totally closed, that's your problem, you're not getting fuel to the engine and it might be a very simple case of a misadjusted barrel.

Other questions to ask yourself:

Are you priming the engine?
Does it fire at all?
Does the little red light on the EZ start light up when you push it?
Have you charged your EZ start battery?
Do your servos move when you turn on truck and radio?
Which glow starter are you using?
Can you see fuel moving to the carb when you prime it?

Let us know what happens. I hate to see a fellow trucker in misery. Been there, done that...

[ammoace]

First and foremost I have a T-Maxx and went through what you are now.
My LHS gave me a glow plug with a idle bar on it and that helped. Also we leaned it out just a tick at a time while trying to start it. Once it started we messed with the throttle until it idled. ALso we had to adjust the idle setting a tiny bit too. And last but not least we took the blue wire off and used a seperate glow igniter. Try not to mess with the low speed needle too much unless you have an extra long precision screw driver because it is hard to reach otherwise.
AMMOACE

[JayJ]

Apache:

I haven't looked at the carb like you said, but I did look at it with the engine off and compared it to the illustration in the manual and it looked fine, but I'll try your suggestion, too. Answers to your questions:

1. I am priming the engine.
2. It does fire. At one point, I actually got it to run, but it died as soon as I tried to move it. Most of the time, it only idles for a couple seconds after I disconnect the battery, if it doesn't die right away.
3. The red LED on the EZ Start does light.
4. The EZ Start battery has a full charge (I'm actually using a Sanyo matched pack charged on a Novak Digi-Peak charger :). Maybe wasteful, but I'm not much into electric anymore.)
5. All servos work properly.
6. I tried using the glow starter that came with the truck as well as the heavy-duty glowplug, part #3231.
7. I can see fuel moving through the line to the carb.

I would write more, but I'm going to be late for work. Ammoace, thanks for your help, too. I'll certainly consider that this evening when I go back to my LHS. Thanks, guys.

[Jwelch]

Ammoace, you used a plug w/ and idle bar?? Didnt it hit the piston??

[ammoace]

Zwelch,
It hasn't hit the piston yet. Knock on wood. :D I will have to ask the LHS which one the put in. I gave him the truck for a day and he added that plug while I wasn't there, free of charge by the way. The guy that runs my LHS is very pro LOSI so Traxxas is alien to him until recently. In fact he didn't have one single Traxxas part in stock until I had him order me a T-Maxx. And while the box sat in his shop 4 or 5 more people asked him about it and 1 of them ordered two. Now he keeps Traxxas parts on his wall. If you want the part number and manufacture I'll ask him.
AMMOACE

[DerekB]

I wouldn't use a plug with an idle bar unless your flying a plane!

Here's is some things to try:

1: Lean out the lowend on the carb. They are usually set rich.

2: Prime the engine with the air filter off. Make sure the fuel is in the carb and try pumping the throttle. Sometimes an engine will fire at 1/2 throttle sometimes at full.

3: Borrow a glow ignitor and use that instead of the ez-start.

I'm betting the low end is set too rich, try that first.

[ammoace]

DerekB,
Why not use a plug with an idle bar except for airplanes? This is my first Nitro engine and don't want to hurt it.
Thanks
AMMOACE

[SidRCUK]

Have you tried blowing through the fuel line, there might me a air blockage, I've got a T-maxx which i'm getting rid of it, but thats my opinion,and thats what happened to me.
Good luck
P.S the first upgrade I would get if I were you would be a Robinson Racing steel spur gear, I had two plastic ones and tey both MELTED :eek:

PLEASE DON NOT TRY AND BYPASS THE FILTERS. IN FUTURE POSTS TRY NOT TO USE FOUL LANGUAGE!!!!!!!! thanks

[ 05-20-2001: Message edited by: DerekB ]

[DerekB]

Amm, it won't hurt the engine, but it will run better without the idle bar.