• Welcome to RCTalk! 🚀

    Join the #1 RC community where hobbyists connect, share, and get expert advice on RC cars, trucks, boats, drones, and more!

    • ✓ Friendly & passionate RC enthusiasts
    • ✓ RC tips & troubleshooting
    • ✓ Buy, sell & trade RC gear
    • ✓ Share builds & upgrades

starting issue

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
P

pondy

RCTalk Member
Messages
31
Reaction score
0
Points
0
RC Driving Style
got a 2.5r t maxx of a friend very cheap, i didnt have any drive so i replaced all req parts, it will start fine and drive fine for about 3 mins untill it warms up, if you let of the throttle so it goes down to idle i eart will die and wont re start untill its cooled down, its on the factory carb setting, if you do get it to start hot it will cut out when you remove the glow starter. have taken motor to a hobby shop who told me the compression is weak, which seems fair as its fairly easy to turn over with one finger. so does it sound like it time for a new engine?

what engine do you recomend for cheap, another 2.5? 3.3 or a picco 21 (gets my vote) with the 3.3 or picco will i have to replace any drive line parts, i just want a drop in motor with no hassle!

sam

i just read that with the picco you need to upgrade the driveline, what about with the 3.3?
 
hi mate my friends t maxx is doing nearly the same it will start but as soon as we touch the throttle it will cut out
have you tried looking at your carb is that all working ,,,are you putting the right mixture off fuel into the car if yes then yuo might have to look into a new engine
regards what engine if you puta 2.5 in you will be ok but if you put a 3,3 in you will have to upgrade the drive shafts as you will snap them on your firs outing lol
hope this helps mate
good luck
graham
 
You could try sealing the engine and making sure the head bolts are tight. This may get it to run more reliably. But if it's short on compression, the engine is on it's last leg. Though I have a 2.5 that has hardly any compression, runs all day and will even pull wheelies. It did exactly what you describe until I realized the head bolts were loose and got 'er sealed up right.
 
the engine is sealed, i suspect carb is working fine as its screams unill its warm, it will still run when its warm, but if you let it go to idle it will cut out and not re start
all head bolts are tight, head has been removed last night

whats the performance differnce bewteen a 2.5 and the 2.5r??

have found a 3.3 brand new cheap, whats the performance differnce on this? do i really need to change the drive shafts? or is this overkill?
 
i went with another 2.5 engine, i would love the extra power of a 3.3 but not intrested in breaking parts, only using the truck as some weekend fun, nothing to serious
 
If you want a little extra kick out of the 2.5, you could always step down to an 18t clutch bell. Or 19t bell and 74/76t spur. The lower gearing helps the small engine in the torque department, and will even make it run a bit cooler. My Maxx ran pretty well with 18/72 gearing and 3.3 tires. With a shot 2.5.:)
 
Metalhead Matt said:
If you want a little extra kick out of the 2.5, you could always step down to an 18t clutch bell. Or 19t bell and 74/76t spur. The lower gearing helps the small engine in the torque department, and will even make it run a bit cooler. My Maxx ran pretty well with 18/72 gearing and 3.3 tires. With a shot 2.5.:)
Click to expand...

will see how i get on, just got a couple of spur gears for cheap, got a 70 which is stock yes? and a 64, using a stock bell gear
 
72 is stock. So your 70 and 64 will yield a higher top speed, with less acceleration. That's on an engine that has the power to push higher gearing. A 2.5 does not. Unless you run street tires around the stock size or smaller, you'll hamper performance with the smaller spurs. Especially the 64t. The engine may even over-heat.
 
ok, i had a 70 on there before, so thats what i got when i replaced it, I'm new to these so still learning :D
 
The learning never seems to end with this hobby. Always something new to discover. It's one of the best parts. As far as your gearing, you could always use your smaller spurs if your going to be driving on the street or parking lots. If they dog ya out too much, you could always just keep them around for spares or if you ever upgrade to a 3.3. A 3.3 will pull some higher gears around. If your just a general basher, the stock gearing will probably suit you about the best. 20/72 is stock. Like I said though, I really like 18/72. It makes a nice difference in acceleration and torque. Just remember when you play around with different size gears, you'll most likely have to make adjustments to the small throttle linkage. That way your carb opens and closes all the way. Just check it out before you run it when you change gears.
 
hey i got some issues with my 3.3 i can't get it to idle at all when i bring it in and stop it it will idle for 3 sec and die and when it dies it clicks i herd the click is just the trans but the performance is good as long as you dont try to idle i have tryed and tryed to adjust it i took it all back to stock settings and still nothing i replaced the glow plug and she scremed for awile and it seemed it fauled out or something and when it dies it takes half a battery to get it back running please tell me something good ha ha
 
rockjunky09 said:
hey i got some issues with my 3.3 i can't get it to idle at all when i bring it in and stop it it will idle for 3 sec and die and when it dies it clicks i herd the click is just the trans but the performance is good as long as you dont try to idle i have tryed and tryed to adjust it i took it all back to stock settings and still nothing i replaced the glow plug and she scremed for awile and it seemed it fauled out or something and when it dies it takes half a battery to get it back running please tell me something good ha ha
Click to expand...


whats the compression like? i can turn my flywheel easily with one finger, dont take much force, not good
 
I'm not sure i can turn it over with one finger it seems to have pretty good compression it will pressure up then finally roll over
 
3.3

Hey i got a 3.3 on my 2.5 i have no problem at all with breaking parts iv had this motor a year now and probly about a gallon of fuel no problem with shafts I'm able to flip the thing over with tht motor its got a 13t clutchbell with original 73t spur the only problem is it revs out quick after hitting second id go with the 3.3 its a cheap 160bucks for a new one
 
Old2.5 said:
Hey i got a 3.3 on my 2.5 i have no problem at all with breaking parts iv had this motor a year now and probly about a gallon of fuel no problem with shafts I'm able to flip the thing over with tht motor its got a 13t clutchbell with original 73t spur the only problem is it revs out quick after hitting second id go with the 3.3 its a cheap 160bucks for a new one
Click to expand...

13t clutch bell? I'm willing to bet that it isn't. 1. Not enough adjustment to mesh the gears. 2. No room for bearings in the bell. 3. Nobody would like a Maxx that tops out at 20mph.;) Throw some pics up if your sure that it's a 13t. I'd like to see the setup.
 
Metalhead Matt said:
13t clutch bell? I'm willing to bet that it isn't. 1. Not enough adjustment to mesh the gears. 2. No room for bearings in the bell. 3. Nobody would like a Maxx that tops out at 20mph.;) Throw some pics up if your sure that it's a 13t. I'd like to see the setup.
Click to expand...

sry wasn't 13 i have an 18 or 20 on it but stock was 23 i think but it works great with 18t bell and 68t spur lots of torque ok top end
 

RC Builds

Back
Top