• Welcome to RCTalk! 🚀

    Join the #1 RC community where hobbyists connect, share, and get expert advice on RC cars, trucks, boats, drones, and more!

    • ✓ Friendly & passionate RC enthusiasts
    • ✓ RC tips & troubleshooting
    • ✓ Buy, sell & trade RC gear
    • ✓ Share builds & upgrades

Problems starting a TMX 3.3

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
m.beas92

m.beas92

RCTalk Rookie
Messages
20
Reaction score
0
Points
0
Location
CA
RC Driving Style
  1. Bashing
  2. Racing
Hi there, I bought a T-Maxx 3.3 two ago from a guy off craigslist, it was working very well the first day I got it. It turned on smoothly and didn't give me any problems. The next day I couldn't get it to turn on, when I plug the EZ Start controller into the truck and try to start it up it just clicks and doesn't do anything. The flywheel, along with everything else clicks when i press the EZ Start button. I was reading the manual and I was thinking it might be a flooded engine, the manual says to use the EZ Start to turn on the engine while the glow plug is off to release any leftover gas in the engine. So I couldn't do that. I noticed that the flywheel is almost impossible to turn while the truck is off. I'm pretty clueless as of now, there's a hobby shop near my house so I can go ask over there but I rather not get charged for a simple fix, if it is something simple.
I'm fairly new to the Nitro R/C hobby, before this T-Maxx i had a little Stampede :p: so this is a huge step up for me. Anyways, if the forum has any suggestions or know whats giving me problems on start up I'd greatly appreciate it.

-Thanks:)
 
I would strongly recommend you take your engine apart before trying to start it again. If you can't move the flywheel at all then its probably your conrod . Take the engine out and completely strip it . Just remember where everything goes . Its alot easyier than you think . And will save you a heap instead of throwing at lhs everytime something happens to it .
 
Alright I'll go try this in a couple minutes and report back here with the results. Thanks guys.

---------- Post added at 4:32 PM ---------- Previous post was at 4:12 PM ----------

As I was doing the removal I noticed that when I held the truck up and tried to spin the tires only the back two moved and when i spun the front ones, only the front ones moved. Aren't all of the wheels supposed to spin?

Ok so I removed the engine and I got the flywheel to move. I reattached everything and attempted to turn it on again. Now the engine actually spins but still no turn on. The ez-start just spins the engine no matter what I try to do.
This is frustrating :(
 
Last edited:
first off when u spin the front tires if you only spin one it will only spin the front. but if you spin the front the same way at the same time the rear will spin..

you might need to seal your engine.. thats the hard part about buying used for your first nitro, or anything for that matter... but yeah seal the engine clean the carb reset needles to factory settings. make sure your lines have no leaks, and make sure your tank is all good. expetialy the cap make sure that is tight..

are both lights lighting up on your wand?? is the fuel making it to the carb? did you try hitting the throttle acouple times? is it a new plug??? and what fuel are you using??

that should cover almost every angle.....
 
I'll be trying this stuff tomorrow and I'll see what happens.

Well both lights on the wand turn on, the motor spins and everything now just that it never actually turns on. Not sure if fuel is going to the carb, I tried pushing the throttle as i turned it on to send some fuel through but that did not help either. I'll go buy a new plug tomorrow to see if that helps. And I'm not sure what fuel the guy gave me, I'll also be buying fuel tomorrow.
 
put your finger over the muffler while you turn it over until you see the fuel get to the carb. and then let go of the muffler and keap turning it over, tap the gas slightly if needed.. i would go with 20% odonells racing blend, trinity monster horsepower, stuff like that,, dont go with traxxas top fuel!!!! bad results for some mest up reason(too much oil) you would think they would know what they were doing but aparently not!!! good luck!!!
 
Ok, well I opened my engine up and I found out what was stopping my flywheel from spinning around. Apparently there was a piece of broken metal inside the engine and it was in between the sleeve and the piston head so whenever I was spinning the flywheel the metal debris would impede the movement of the piston. I bought this T-Maxx used so the guy before me must have dropped something inside the engine. I've removed it and it no longer gets stuck when I try to turn on the engine. I just need to get my glow plug as soon as possible to get my t-maxx turned on. That was some good advice mtaylortank :P
 
how is the fit between the piston and the sleeve now??? make sure there is still good compression... and that piece of metal could of come off the piston. keep us informed on progress.. I have been through alot of different problems with my maxx's I have enough to def. keep me busy... good luck
 
Alright so, I tried to turn on my T-Maxx again this morning. I went to my LHS to get some O'Donnell 20% Fuel and a hot glow plug because it was what the shop guy suggested I should use for the TRX 3.3. I come back home; install the glow plug,fuel up, check my lines and everything seems good. When I began to start the T-Maxx I made sure to prime the engine so I covered the exhaust and watched the fuel get near the carburetor then released my finger and tried to turn on the T-Maxx. I got no results, the good thing is that the flywheel doesn't get stuck anymore the engine actually spins, it just doesn't turn on no matter how much it spins. So that's where I am at right now. Any other ideas would be appreciated.

Also, the day that I got it I accidentally flipped the truck with the shell off and when I flipped it back over the engine got really loud so I turned it off, the morning after this happened it turned on for like 4 seconds, I tried to apply throttle but it turned off on me. After that I haven't been able to get it running :/ Could that flip over have something to do with it? It was going slow too so I don't know what the heck happened.
 
Last edited:
Hey you know what? I was looking at the connection rod again and I noticed that there was a gap in the middle of it.

http://ecx.images-amazon.com/images/I/413ZDQGW2XL._SL500_AA300_.jpg

See in that picture how there is a little groove in the middle of the rod. Where that groove is in that picture is where the gap is on my conrod. Could that be causing the malfunction?
 
yeah that could be part of your problem.. turn the fly wheel and see if you feel any compression in there as you feel the piston go up and down.. that peice of metal might have done something to the seat between piston and sleeve.. you can sometimes find the set of three on e-bay, I beleive that will be your cheapest way to get those parts because the cost about 80 at a shop...

were you fluttering the throttle at all while youj tried to start it???

When you say it got loud was it the manifold cracking or pulling away??? if you dont have a good seal with the exhaust it doesn't want to run right either...

if you are going to replace the conrod I recomend the davis diesel conrod.... heard nothing but good things about them.. I havent myself because I dont want to have to reseal my engines considering I am running 4-5 trx 3.3's but that is my next step myself... last alot longer than the stock one because the stock one is the same one they use in the trx 2.5 just figured I would add that before you bought your new parts..
In my opinion I think the guy you bought this thing from knew it was having problems.. You should always see them run and start them yourself before buying, but I know how it is to remember to do all that when you just want to get it home and play around with it.
 
Last edited:
There definitely is compression when I spin the flywheel, as the piston goes to TDC I feel it get harder to spin then when its dropping it gets smooth again so the compression is definitely there.
I've tried flutting the throttle but it did not help. I get the same result.

What I was saying about the engine trying loud I'm not sure what happened but it just started screaming, it was making a high pitched sound. I checked later that night and I saw the spur gear was really stripped. I replaced the spur too. Could I have tightened the spur too much and that's why its not starting? I believe I did it correctly.

And also, I asked the guy to run the truck for me. It started very quickly then when I got home I tried starting it myself and I used it for about a minute then I flipped the truck over and that's when everything started happening; loud noise, spur strip, so I just turned it off and I didn't try to turn it on until the next day and since then I haven't been able to turn it on.
 
check your head bolts and your exhaust bolts I wonder if any of those got loose. well you have had it opend so you would have messed with those. did you seal the engine when you put it back together???
 
If the con rod is split there is no need to try and start the engine, you need a new con-rod. If you were to get it started with a split rod it would most likely split further and completely come apart which usually will do more damage and result in a trashed piston and sleeve.
 
Do you guys know a good site for buying R/C parts? I'll just replace the con-rod
 
 
Aaaah yep...You definitely have a split con rod. It also looks like someone has filed/sanded the bottom of the piston skirt opposite the cut out.
Head gasket was leaking badly at some point and the head button shows substantial detonation has occured.
Is that a gouge in the bottom of the crankcase where the crank and con rod groove is?

I personally would keep that engine for a parts engine and ebay a new mill.
 
No I believe the crankcase is normal from what I've seen. So what would you say to do? Buy a new sleeve, rod, and piston? Or just send the motor in to Traxxas for an exchange?

I'm not really motivated to spend $200 dollars on a new motor I just want to get it working again I don't want this to be a money pit :/

What do you mean by a "new mill?"
 
Mill = engine.

I would not rebuild that engine from the looks of it but that’s just me and my experiences. By the time you replace the rod, piston and sleeve you almost have the price of a new engine. If the bearings need replaced that’s another cost.
You can purchase a new 3.3 engine on ebay for around $100 and sometimes cheaper.
 

RC Builds

Back
Top