trx 3.3 and diff help

[yamabraaaper]

Hi I'm the not so proud owner of a tmaxx 3.3. I'm the third owner and have had nothing but trouble, I've sealed and resealed the engine a hundred times and still have oil everywhere its spraying from the flywheel, and the header and plastic back plate from the pull start are covered in it. its leaking a thin black liquid from the gap between the black plastic and brass on the hsn. I've replaced the tank, fuel lines, pipe, header (with no rubber oring just sealant),front bearing, clutch shoes, flywheel,and rebuilt the carb. I've taken the engine apart completely and cleaned/oiled every part. I can push the piston through the sleeve with about 1/4 inch until flush with the top (cold). I've pressure tested it after sealing it and it only leaks from the brand new front bearing ( doesn't explain the oil everywhere)I'm unsure if its a problem or not but the rear diff is locked.


I had re sealed and cleaned everything one last time, got it built, tuned it, and it ran like a dream. Ran between 180 and 210 Fahrenheit any more lean and it would cut out at mid throttle. in the process of tuning it wouldn't get past half rpm and sounded like death untill the sweet spot where it would wheelie from a stop. After about 5 min of running it would die and not start unless at 3/4 throttle even then it would die five feet from me and be really hard to start. After running for a min the one way would slip until I let it sit and dry out.

Sorry this thread us so roughly put together I was thinking of problems as I went.

 

[Reddog]

It sounds like your mill is worn out. As for the read diff lock, remove it. I did not take this advice right away until I took a look at my brand new gears after 5 tanks of fuel and the rear gears were all but shot due to the diff lock. Just my 2 cents worth. Shaun

 

[yamabraaaper]

It sounds like your mill is worn out. As for the read diff lock, remove it. I did not take this advice right away until I took a look at my brand new gears after 5 tanks of fuel and the rear gears were all but shot due to the diff lock. Just my 2 cents worth. Shaun

Thanks shaun I'm new to forums so mill = piston/sleeve correct? And thanks for the info I had no clue the rear diff should be free.... how (if at all) does a locked diff effect the handling?

 

[hotrodrob]

Mill=engine....
Man I wish you would of asked us earlier on,the $ you said you spent on replacement engine parts+time involved you would have been better of just doing the traxxas trade in deal!......sounds to me you may have your needles backward ontop of the p/s being worn out bud

 

[yamabraaaper]

Mill=engine....
Man I wish you would of asked us earlier on,the $ I ou said you spent on replacement engine parts+time involved you would have been better of just doing the traxxas trade in deal!......sounds to me you may have your needles backward ontop of the p/s being worn out bud

Thanks "hotrodrob" sorry again...

Mill=engine....
Man I wish you would of asked us earlier on,the $ you said you spent on replacement engine parts+time involved you would have been better of just doing the traxxas trade in deal!......sounds to me you may have your needles backward ontop of the p/s being worn out bud

Thanks hotrobrod again sorry to ask but what do you mean needles backward? Like as in tune? If so which one should i richen/lean?

 

[hotrodrob]

What I mentioned was you may have one too rich and the other too lean!..it's not all that difficult to do really,..set back to factory with the 1mm "at largest" idle gap...those trx mills like to be run a little on the hot side so don't be scared when Temps start reaching 260-280...260 is about the perfect heat range on those 280 is still ok don't let it get hotter than that they wear out faster

 

[yamabraaaper]

Ohh thanks, how do I avoid this in the future? What are the signs of needles being backwards?

What I mentioned was you may have one too rich and the other too lean!..it's not all that difficult to do really,..set back to factory with the 1mm "at largest" idle gap...those trx mills like to be run a little on the hot side so don't be scared when Temps start reaching 260-280...260 is about the perfect heat range on those 280 is still ok don't let it get hotter than that they wear out faster

 

[Cat]

What are the signs of needles being backwards?

Back to factory settings. HSN 4 turnst out, LSN flush with carb side.Idle gap 1mm.
Of course you can chase the correct setting. But it would be like looking for a needle in a haystack.

(Red screw even with yellow edge)

 

[hotrodrob]

What pipe and filter you running?

 

[yamabraaaper]

What pipe and filter you running?

Stock filter that comes with the 4907 and the tuned resonator pipe. The pipe is new b/c it previously had a black pipe that according to my lhs was for a big block and didnt have the backpressure needed

the pipe says "RB" t/maxx

 

[yamabraaaper]

Well after the last run before it ran bad it must have been lean. The piston just falls to the end of the sleeve its so loose and \/ the piston skirt broke and

I can't find the chunk anywhere

 

[Cat]

That P/S i deficiently worn. Exactly the same happen to my engine regarding the piston.

 

[yamabraaaper]

That P/S i deficiently worn. Exactly the same happen to my engine regarding the piston.

Well thanks to all that replied. I ended up just biting the bullet and getting a new 3.3 With the trade in program.

 

[hotrodrob]

There you go man!...take your time with the break in and be patiant

 

[yamabraaaper]

There you go man!...take your time with the break in and be patiant

I have already sealed the new engine but I'm I'm the process of a deep cleaning so what break in process do you recommend?

 

[hotrodrob]

To keep it simple just use the heat cycle method/traxxas method....go the the engines section here on rcnt and check out the stickies at the top of the page