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totally puzzled

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darnoced

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Location
Halifax, Nova Scotia
RC Driving Style
  1. Bashing
I was out bashing the other day, and I inadvertantly ended up upside down in a brook. The engine was totally filled with water, so I took it home and tore the thing completely apart and dried everything up, oiled it all with a thin film of light oil and re-assembled it. Now it starts right up, but to get it to even come off an idle I have to lean the HS in to about 2 - 2 1/2 turns. This of course leads to the thing overheating and shutting down in short order. I was pretty careful in re-assembling the engine so I am pretty sure that everything is where it wants to be, however there is something not right and for the life of me can't figure it out. The 2.5 is of unknown age as I got it in the box with the rest of the truck.
Sorry for being so long winded, but I am darn near ready to shoot the thing and send that in to traxxas for a 3.3(they do say as long as all the parts are there don't they?). I have no idea what good or bad compression is or what the pinch really means so I have no idea if the engine is just finally worn out or what. The piston looked fine(no scratches or pitting) just a little black on the top and the sleeve didn't appear to have any scratching.
Any suggestions would be appreciated.
 
When it is idling, and you give it throttle, what does it do? Does it idle, then you have to lean it 2 and a half turns?
 
It will start up fine and sit there and idle nicely. When I try to bring it up off the idle the just goes bleah...and dies, even if I pick it up and try. IF I lean the HS back from 4 turns to about 2 and a half turns then it will go for about 2 - 3 mins and it is overheating like mad. I've tried setting the LS to everything from about 1 and a quater turns to 2 turns with no luck.
Hope this is the info you wanted.
 
Did you dry/clean out and relube your air filter?

I'd pull the carb apart and take every piece out of it and clean it really good with DA and compressed air. May have gotten something in it that is clogging a needle seat. Although, it sounds kind of like it's flooding on you. (no pun intended ;)) I mean it, really flooding due to an obstruction or something.

Did you get any mud stuck up in your exhaust? Half clogged exhaust would cause it to run ridiculously rich and doggy.
 
you might want to put everything back to factory settings i drownded a another nitro not my t-maxx but my firestorm i had tons of water in the exhaust and i took it all apart and put everything back to factory and just had to return it. just make sure everything is all dry
 
Yes the air filter is dry and re-oiled. The exhaust is dried out. Luckily it ws a clear running stream so there was no mud to deal with this time. I did take the carb apart as far as I could (everything except the piece that the slide goes into) and made sure that it was all water free. The one thing that I was a little puzzled about putting it together was the plastic piece the the fuel line goes to lining up with the hole in the brass piece that the HS needle goes into. I did take the HS completely out and crank it over and there was fuel coming out of the place where the needle goes in. I assumed that this meant that all was well.
I looked around the front bearing and it is nice and dry so I guess it is not leaking. I haven't taken the engine back out again and checked for fuel around the OWB yet as right about now I would see how well the garborator would feed on a 2.5.

I just took the exhaust off the manifold and blew though it (took the pressure line off to the tank as well). Is it supposed to have some restriction in it(it is a stock black plastic pipe) when you blow through it? If not, how do you take it apart to clean it out?
 
I guess it is a 1/10. The one that came stock on the 2.5 T-maxx. I don't even know exactly how old this truck is. When my son got it for $40 it was in pieces in a box.

the stinger hole is maybe 1/4" at the most.
 
I think that I found the problem taking the thing apart (again). It would appear that the brass piece that the HS needle screws into stripped the plastic threads in the carb body(must have been dropped cause I would NEVER tighten it too much..lol).
Anyone know of a way to fix this without buying a new carb body(lhs down't have one in stock, but will order it in..of course..grrrr)
 
Almost any type of adhesive you use will get eaten away by the fuel.

In a pinch, try the long cure JB weld... but you may have to replace your whole high speed needle assembly aftwards... might just want to wait for the new body to show up. ;)

The reason I say long cure is because I've had it hold up better to nitro fuel than the quick cure stuff. It also has a higher heat rating.
 
I picked up some one minuite epoxy and just coated the threads. stuck it in making sure the passage was not blocked and held it in tight. I don't think that the fuel will get to the epoxy so I'm hoping it will hold until I have to tear it apart again.
The engine is almost spent so I didn't want to spend any money on it anyway so it should be ak to send in for a shiney new 3.3 :-)
 

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