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shoshe

RCTalk Basher
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Winterport
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I have a tmaxx 2.5 completely stock. I can only run it for a few minutes then it'll stall (somehow it always does) and the I can't get it started again until
I let it sit. This is the old 2.5 with the old style cooling head. My temps never get over 200. Do I need a new motor?? I don't want to oversize because I can't afford to break everything.
 
Need more info.. How much fuel has been thru the engine ? Was it broken in properly ? Could be as simple as needing a low-end needle adjustment . Might need a new glowplug . Could be a fuel line with a small hole in it or an air leak .
 
I cannot answer the the first 2 questions. I bought it off Ebay used, it runs excellent when it runs. I have put 6-7 tanks of fuel through it myself. The seller claimed that it only had 5 tanks and was broken in properly. But when I got it, it seemed to be older than they let on. I've been adjusting carb, got it to run excellent, but when it stalls for some reason or another I have a tough time getting it started again, then it runs great then the whole process renes itself.
 
Before it dies does it rev up alittle ? Check the seal on the fuel tank lid . Check the fuel pressure line coming from the exhaust . Check for cracked or brittle fuel lines and when in doubt.. set the needles back to factory settings and retune . Also when tuning the engine over by hand does it feel like there is alot of compression ?

Stock needle settings are : High speed needle 4 turns out from closed
Low speed needle flush with the end of the slide .
 
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PHX- Thanks, went back to factory settings. My low speed needle was in WAY TOO FAR, I backed it out 2 turns until it was flush. After I set both to factory settings I started it up and immediately I could just HEAR the difference with it idling. I ended up turning the high speed needle 1/4 turn in and now all of a sudden my truck's doing wheelies. I was wondering why this thing seemed a little sluggish. I ran it for a few minutes then shut it off, and tried to start it again, and it fought me but it ended up starting right back up.
Are my carb settings going to stay? My duratrax is very inconsistent with it's tuning (I also took this back to factory settings).
 
Well I've had 2 2.5's and one held a tune very well and the other didnt . Some guys swap out the traxxas carb and put an O.S carb on and that usually makes the engine run better and more consistent . Ill see if I can find out what carb others use .

Here is the carb some guys swap to http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXCA07&P=7 I've never tried this so I dont know how well it works .
 
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I've noticed that at factory settings it spits a LOT of gas out of the exhaust, so I went in 1 turn on the low end, 1/8 turn in on high, and it seems to be doing really well. At first the thing was doing wheelies, then I let it sit for a couple of hours went back and it was flooded bad.
I think my engine is good and my carb is toast, probably the reason the guy sold it in the first place.
 

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