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Bkyd Basher

Bkyd Basher

RCTalk Addict
Messages
1,090
Reaction score
20
Points
158
Location
Stamford Ny
RC Driving Style
  1. Bashing
  2. Racing
Hey guys, havin a real problem keepin my buddys max running good. Seems like it gets hot and runs like crap and doesn't wanna idle. It is pretty hot out but my revo handles it fine. I actually took the heads of both motors and my piston and sleeve actually looks worse than his. And as i try to richen it up to keep it a lil cooler it is way to rich, ton of blue smoke and doggy. Could it just be to warm out to run for a long time or could his motor be on its way out?
 
yup engine is sealed. I've tried dam near everything, i went through the tuning guide also. Just a while into a tank it starts. I dont have a temp gun but it gets pretty warm. Shut it off and let it cool and it runs great till it heats up. I'm at about 3 1/2 on the HSN and 1 1/2 on the lsn.
 
maybe its just to lean ...if i run either of my 3.3s at 3 1/2 turns on the hsn , they overheat pretty quick ... i run them at about 4 1/2 to 5 turns out ...thats how they like it ...and the lsn is about flush to the housing
 
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I just had to replace the 2.5r in my revo I bought used. It would run great until it got hot and then it would die and wouldnt restart until it was cooled off.

After some reading on here I got it hot and let it die and then turned the flywheel to check compression and I could literally turn it with my pinky finger with almost no resistance. I figured instead of putting a piston and sleeve in it I just spent $100 and did the power-up deal and got a new 3.3
 
do u think the 1 1/2 on the lsn is to lean? It puts it about flush. It is about 85 in the sun here today. And also if i were to rebuild can i just do a piston and sleeve? or do bearings and everything. If i should do the bearings and everything i will just buy a new one. And if i were to buy new whats ur suggestions for a bolt in descent priced motor? Thanks guys
 
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I've encountered this same scenerio with 3 2.5's. Sealing them took care of the problems. Even on well worn engines. It's always worth the hour or two it takes to seal an engine unless your already dead set on a new one. Every nitro engine should be sealed before running anyways.
 
He actually bought the truck used but the motor was fairly new, id say a gallon maybe 1 1/2 at the most. So i went through the truck and did seal the motor. It ran very well for quite a long time. It probably has maybe 4 gallons through it, but most likely not even that much.Seems when its cooler out it runs ok, but bein so hot it gets hot very quick. I cut holes in the body and also just noticed the brake was on just slightly. Gonna wait till the weather temp cools a bit and try again.
 
is it a 2.5 or 2.5r,i have 2 2.5 maxxs' here both bout the same age and maybe 2 litres on them both if i'm lucky which hadn't been started in nearly 7 years. 1 i put fresh batts and a new plug and some fuel lines and she runs like a champ didn't even have to tune it!

the othe one well thats a different story i've tried everything to get that pig to run i even put a brand new carb on it but it still gets hot,sealing made no difference

so i guess what i am tryin to say is that if it doin what its doin i'd do a piston and liner you'd get away with the bearings but i'd change the rod and get the o-ring kit for the carb and i recon you'll be sweet
 
Thanks alot guys. So i went back to a real rich tune and restarted,(after the temp outside dropped about 15 degrees). Got it to sit and run, started leaning out little by little on the hsn and boom Running like a raped ape, sits there and idles fine. Guess it was all in the tune but with it bein so dam hot outside it made it hard to find a good tune.After about 8 tanks later and a ton of laps he ended up with just front wheel drive. Tore the rear diff apart and differential has two grooves that the pin sits that holds the two small gears in place and it twisted the pin around tearing up the groove in the diff. No big deal parts are on the way and i was gonna take it apart to put diff fluids in anyhow. Thanks alot for the imput and a new motor may still b in the near future. By the way it is a 3.3.:D
 
Well glad ya had a good outcome I've found the 3.3 much eaiser to tune just keep an eye on the o rings round the I had a big prob with a rebuilt 3.3 that wouldnt run good at $4 for a carb kit now shes sweet
 

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