https://photos.app.goo.gl/DCfzcGEX25BR4CqGAHey Y’all, I bought an old Traxxas Tmaxx over 2yrs ago for $50 from a friend’s neighbor. It was given to him by the original owner, but my friend’s neighbor had no idea what to do with it. I think it may be from the first year they were built, but I could be wrong. It sure ain’t anywhere close to new. If you read my ‘about me,’ you’ll see that my occupation is listed as “small engine mechanic...” cause it is. I’m familiar with engines. Besides lawnmowers and chainsaws, etc., I’ve worked on Mazda rotary engines, Nissan engines, chevys... so you can understand why I’m a little frustrated that I can’t get this minuscule glow engine to go. On the day I bought the truck, I was able to get it to fire for a short moment of no more than 5secs, until the flywheel unscrewed from the crankshaft of the TRX .15 engine. Ever since, I haven’t been able to start the thing. The flywheel/clutch assy comes off every time I turn the engine over. The carb works and delivers air and fuel to the engine, the engine has spark, and it has compression(as of 2yrs ago). I just don’t know why the flywheel and clutch keep coming off. The video I took and put at the top of the post shows you what I’m dealing with. Any and all help is appreciated! My goal is to bring the truck to a local track on a practice day and drive it around when I’m not practicing. I’ve rebuilt the transmission, since I thought that may have been the issue at first. I don’t think it was, and I’m not sure what I was thinking lol. The trans has no fluid in it now, and didn’t when I bought it. I’m not sure if it needs fluid, since it does have a port on the top for it. Thanks in advance for your help!

Thanks, looks like I’ll service the clutch. I’ll report back, afterwards.

Alright. I rebuilt the clutch and it no longer comes off. Thank you. This little engine still won’t cooperate with me, though. I spent 2 hrs on it today. Ridiculous! I have burnt through a starter motor. Thankfully I had a spare. I changed the glow plug, even though I knew it was getting spark. I can get it to start, but it stalls instantly. No carb tuning can solve this, I tried. After some more research, I think the issue may be the one way bearing in the ezstart. The engine sounds like it’s thrown the rod when turning it over in the higher rpm’s. I took off the ezstart to check it, and it’s fine. It’s a little gunked up in the sump, and there are some metal sparkles in it and a bit of grime, too, but not terrible...but not great. I expected that. The piston is borderline immaculate. I have a spare, brand new engine, but I don’t think a new engine will solve the problem. TBH, I don’t want to put the new engine in. I am committed to forcing this original tiny block of aluminum back to life.

Thanks again. Not using a glow igniter, since I don’t have one. I’d have a few if I raced nitro. Compression is surprisingly good. The carb is seated well. I’ve played with the carb and have plenty of experience with carburetors. I haven’t cleaned the carb yet, since it’s delivering air and fuel as it should. Lol I’m not sure what I was talking about when I said the engine wasn’t terrible. It’s pretty bad. I’ll look at it a bit more tomorrow. Then I’ll be off to work fixing lawnmowers. Once I get this running, I plan to completely rebuild the entire truck, including the engine, carb, etc. The thing probably has 20 years worth of encrusted nitro fuel and dirt on it.

Alright, so the one way bearing is fine. I’m stumped, and frustrated at this engine. I sprayed the crankcase out with carb spray to get a little bit of the gunk out and put the sump cover and everything else back onto the engine. Still won’t go. Any other ideas?

Well, I got the engine running for about 30 secs. Like I said, the carb is fine and it’s getting spark. Now I think there’s another issue with the ezstart. The ezstart gears are all intact and the brushed motor works but it doesn’t turn the engine over.

There is no “spark” with a nitro engine. The glow plug just glows orange.