t maxx problems

[pondy]

got my hands on a second hand t maxx, have seen it run and it went well, it took a while to start and when trying to start alot of fuel came out of the exhaust, but it always started

i got my hands on it, put in a new glow plug, changed the fuel and charged the batterys, it will turn over untill the battery goes flat, dont even try to start, no fuel comes out of the exhaust but is getting into the carb. tried giving it throttle etc but not starting still, any ideas?

if there away to remove all the ez start and have a pull start? any guides on here with pics? i have an old kyosho sandmaster mk2 and it starts 1st time on the pull! good for 15 years old.

whats the difference between the 2.5 and the 3.?

 

[2revo1maxx]

The 2.5 is a .15, 3.3 is a .20. Did you check the plug? If it's good then it's not getting power.

 

[olds97_lss]

If you have an external heater, just disconnect the blue wire from the plug and put the heater on the plug like normal, then try to start it.

Replacing the ez start is fairly straight forward. Take the engine out of the vehicle. Remove the 3 screws from the ez-start holding it onto the backplate, install pullstart, install screws, install engine.

pull-starter: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDGG4&P=ML

You can probably pick one up on ebay cheaper.

YOu can try and test the glowplug/connection by taking the GP out of the engine, connect the blue wire to the GP, hold the GP against the engine head to make contact, then run the ez-starter. The GP coil should glow red. If it doesn't, then it could be the ground wire from the wire harness to the engine/chassis. That wire is needed for heating the GP, but not for the electric motor.

 

[pondy]

the glow plug what no good that was in there, first thing i did was fit a new one and test it on the blue wire, it didnt do anything, but now thinking about it there is a light on the ez start wand for glow plug, it never came on and i no the battery was not that good, i did use an external heater after, but still no good

is it worth removing the ez start, i dont want to wait around charging batterys and carring that want around with me, i just want the track to be simple and start well

so the engine is the ony differnce, how can i tell what engine mine has?
what is the factory settings for the carb, am going to set these before trying to restart

 

[Metalhead Matt]

You might have a clogged hsn. Pull it out and check for debris in the hole. Stock settings are 4 turns out on the hsn, 2 turns out on the lsn. Since your engine is used, these settings will be too rich. I'd start an 1/8th turn short of factory on both needles.

 

[pondy]

got it running today, i think it was a fuel issue. i emptied the tank and put new fuel in, charged the batterys and cranked it over for a few mins, alot of the old fuel came out of the exhaust then it fired up, the fuel coming out looked like rusty water, has been siting around for a few months

I'm new to this so bare with me, I'm guessing you are talking about hight and low speed needles? were on the carb am i going to find these?

once i started it up i found another issue (which i was told about), it has no drive, when its reved the clutch in the bell gear works, the spur gear spins but there is no drive from the other side of the box, so I'm guessing a problem with the gear box so am going to strip it down tonight. how tight is the nut and spring on the end of the spur gear ment to be? is there ment to be oil or grease in the gear box, there is a little rubber bung at the top, what oil do the diff take?

when steering on the ground, the wheels wont turn, when its lifted off the ground they work fine, not sure what its like when its moving along, i was thinking as the tyres are so large it makes it harder to move, or a servo problem.

 

[imtired111]

if the t maxx has the stock 2055 servo, it will never turn on the ground. the response sucks also. try going with a hitec hi torque servo.

 

[olds97_lss]

I'm guessing you are talking about hight and low speed needles? were on the carb am i going to find these?

You can find most of that info here:
https://www.rcnitrotalk.com/forum/showthread.php?t=60832
A couple posts down, there's a "tuning" chart and photo of a carb with arrows and descriptions.
HSN = high speed needle
LSN = low speed needle
MSN = mid-speed needle (TRX engines don't have this)

once i started it up i found another issue (which i was told about), it has no drive, when its reved the clutch in the bell gear works, the spur gear spins but there is no drive from the other side of the box, so I'm guessing a problem with the gear box so am going to strip it down tonight.

If it's an older maxx with reverse, you may have the linkage stuck between forward and reverse. If it does have reverse, you should see a wire/slider sticking out the front of the trans. Moving it one way or the other should engage forward/reverse. However, most (including myself) ditch the entire reverse mechanism for a FOC (forward only conversion). This removes a lot of dead weight and strengthens the trans. Also makes for a much smoother gear engagement.

how tight is the nut and spring on the end of the spur gear ment to be? is there ment to be oil or grease in the gear box, there is a little rubber bung at the top, what oil do the diff take?[/url]

Tighten the nut until the spring is fully compressed, then back it off 1/4 turn. That should get you close.

The rubber bung (that's a funny word ) is to allow you access to the two speed adjustment screw. The gears in the trans run dry, but I always put a little bit of axle grease on them and never had ill effects. Again, if it's an older maxx, the diffs aren't sealed, so you can't run oil. You're forced to run grease inside the little cup. Typical axle grease will do in the cup and on the main ring/pinion gears.

when steering on the ground, the wheels wont turn, when its lifted off the ground they work fine, not sure what its like when its moving along, i was thinking as the tyres are so large it makes it harder to move, or a servo problem.

You can also ditch the stock steering assembly for the newer e-maxx version. This removes the servo mounted servo saver and replaces it with a chassis mounted saver. Much more consistent and accurate.

Here's the parts for the chassis mounted saver:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXTKN2&P=7

And according to tower, you need these:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXHFS7&P=V
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXHFN0&P=V
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXMHY2&P=V

As suggested, the stock servo sucks. I highly suggest you get something with 140oz of torque or more (more is better). Running a 6V hump pack will help deliver more power for your servos.

A servo I'd suggest would be a JR Sport 126M:
http://www.horizonhobby.com/Products/Default.aspx?ProdID=JSP20071

Traxxas has horns for the JR servos:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXHGB3&P=7

Or, you can buy some other brand:
http://www.horizonhobby.com/Products/Default.aspx?ProdID=JRPA215

 

[pondy]

You can find most of that info here:
https://www.rcnitrotalk.com/forum/showthread.php?t=60832
A couple posts down, there's a "tuning" chart and photo of a carb with arrows and descriptions.
HSN = high speed needle
LSN = low speed needle
MSN = mid-speed needle (TRX engines don't have this)


If it's an older maxx with reverse, you may have the linkage stuck between forward and reverse. If it does have reverse, you should see a wire/slider sticking out the front of the trans. Moving it one way or the other should engage forward/reverse. However, most (including myself) ditch the entire reverse mechanism for a FOC (forward only conversion). This removes a lot of dead weight and strengthens the trans. Also makes for a much smoother gear engagement.


Tighten the nut until the spring is fully compressed, then back it off 1/4 turn. That should get you close.

The rubber bung (that's a funny word ) is to allow you access to the two speed adjustment screw. The gears in the trans run dry, but I always put a little bit of axle grease on them and never had ill effects. Again, if it's an older maxx, the diffs aren't sealed, so you can't run oil. You're forced to run grease inside the little cup. Typical axle grease will do in the cup and on the main ring/pinion gears.




You can also ditch the stock steering assembly for the newer e-maxx version. This removes the servo mounted servo saver and replaces it with a chassis mounted saver. Much more consistent and accurate.

Here's the parts for the chassis mounted saver:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXTKN2&P=7

And according to tower, you need these:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXHFS7&P=V
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXHFN0&P=V
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXMHY2&P=V

As suggested, the stock servo sucks. I highly suggest you get something with 140oz of torque or more (more is better). Running a 6V hump pack will help deliver more power for your servos.

A servo I'd suggest would be a JR Sport 126M:
http://www.horizonhobby.com/Products/Default.aspx?ProdID=JSP20071

Traxxas has horns for the JR servos:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXHGB3&P=7

Or, you can buy some other brand:
http://www.horizonhobby.com/Products/Default.aspx?ProdID=JRPA215

thanks, thats answered all my question, i have found my problem, its in the slipper clutch, you an hold the spur gear and turn the shaft on the trans, the shaft going into the gear box is also slightlty bend so the spur gear wobbles when you spin it up, still need to strip the gear box to remove this shaft

how would you go about adjusting the 2 speed?

when i put this back together I'm going to start with factory settings as it still dont start well , i have no idea what has been done to the carb but guessing its to rich, some times the ez start locks up, the motor still spins but the engine dont, so i guess its flooding

 

[knall]

thanks, thats answered all my question, i have found my problem, its in the slipper clutch, you an hold the spur gear and turn the shaft on the trans, the shaft going into the gear box is also slightlty bend so the spur gear wobbles when you spin it up, still need to strip the gear box to remove this shaft

how would you go about adjusting the 2 speed?

when i put this back together I'm going to start with factory settings as it still dont start well , i have no idea what has been done to the carb but guessing its to rich, some times the ez start locks up, the motor still spins but the engine dont, so i guess its flooding

"ez start electric motor spins but nitro engine doesn't crank" You need a new one way bearing.
YES this will be an intermitent problem.

If the engine floods and you one way bearing is good, nothing will spin.

 

[pondy]

ok, better get one of these, sometime it works, when it dont i need to wiggle the motor around and it kicks in

from these syptoms would the motor be running rich or lean? now when its it takes a while to get started, and when it down i csn open the throttle and it will cut out

i have been looking for new shells, all i have found so far is 3.3 shells for extrended bodys, guessing this wont work, if i upload pics of the rc i have can somone confirm what type it is?

 

[pondy]

hello, have another problem, have stripped down the gear box, now putting it back together, down the bottom were the selector fork is, 2 gears how little metal arms that are on one side, there are connected to an allen key bolt, how are there adjusted?
sam