Need Advice...

[Rocfrog]

My little brother has an HPI Savage SS (kit version) with the s-25 motor and he's having problems with it. He did the inital break in many years ago and didn't ever end up running it. But I got my T-Maxx for xmas and so he decided to take his out again. He got the motor tuned and running great but when you try and run it it barely moves and if you try and go off of the smooth pavement it won't move at all. The engine revs up just fine but it doesn't move the truck. He tried taking out the retaining springs for the clutch so it would open up more and grab but it didn't help....

Any suggestions?

Nick

 

[alpinehyperlite]

Check the hex's inside the wheels to make sure they arent stripped, give it throttle and see if the drive shafts are spinning.

 

[ohmygahitscoby]

I'd check the slipper clutch. May be too loose. If not, check the tranny. Are all the gears fine? Is the clutchbell spinning when you throttle?

 

[XxVASSAGOxX]

it has reverse.. make sure your 3rd channel is working. and that it is going into reverse and drive, if not you will just sit there and rev with no action!!

 

[Rocfrog]

Sorry I'm not real good with all the terms....But.....

If you look at this picture the part circled in red doesn't spin when you give it gas and put any resistance on the tires....

Inside there is also where he took out the "springs" to try and help it....

it has reverse.. make sure your 3rd channel is working. and that it is going into reverse and drive, if not you will just sit there and rev with no action!!

I don't believe it has reverse. And if it does he doesn't have a three channel radio to control it with.

Nick

 

[Cyclop3000]

If he messed with the clutch, he could have installed the clutch shoes backwards. What you circled in red is the clutch bell, inside are the clutch shoes (the springs he removed are on the shoes). Check your manual and make sure the shoes are installed properly, and in the proper direction. Check out the attachment I included here. If you don't have the manual, click here: http://www.hpiracing.com/graphics/instr/pdf/861.pdf

Also make sure that when the clutch bell is installed (that thing circled in red), that you cannot see the shoes in the gap between the bell and the engine. But that's secondary. Check the shoes first.

About the reverse...does he have the module? If so, you need the 3rd channel to specify forward or reverse...if he doesn't have a 3rd channel take out the reverse module.

Hope this helps!

 

[Rocfrog]

Ok so he checked all the above and said they were fine.

So he wanted me to mentiont that once it's running and he holds it in the air (all 4 wheels off the ground) the truck runs fine, goes thru both gears and the tires rotate at full speed, but as soon as you place it on the ground the truck barely moves. now to give it some credit it did slowly go thru the grass yesterday but not very well....

The other concern he has is that the gas he is running is well over ten years old. Could this be a problem? I gave him a tank of my new gas and his truck had a hard time starting and when it did as soon as he gave it any throttle it died....

On the reverse he said he doesn't have it...


Nick

 

[Candyman]

If the clutch bell (the part you circled) doesn't spin when it's on the ground and you give it gas, then I am suspecting the clutch shoes are probably slipping like crazy. I'd advise him to disassemble the clutch again. Get a green scrub pad and have him scour out the inside of the gear. Sometimes crud can build up in there and it may be causing slipping. Also, have him rough up the outside of the clutch shoes. And he can put the springs back in. Without the springs, the shoes will try to engage the clutch. But they can also wear a lot quicker. So I'd focus on that area first. Sounds like the most likely source.

 

[NCNitro]

Sounds more like a slipper clutch problem than a clutch problem to me. Tighten the slipper nut all the way down, then back it off about 1/4 turn, no more though.

Another common problem they had was the grub screws would come out of the diff drive cups and just spin with a load on them. Check and make sure the grub screws are still in the cups.

 

[flm_savage]

does the big silver dollar looking thing (flywheel) behind the part you circled spin? perhaps the pilot nut isn't tight and the flywheel is slipping on the collet.

 

[TGL]

If you took the clutch springs out, the clutch should engage (catch) even at idle speeds. At idle and with the truck on the ground your engine should either die (most likely) or move the truck (doubtful). If it doesn't die and doesn't move, it sounds like your clutch shoes aren't engaging properly. Usually in these cases the clutch shoes are either binding and not catching the clutch bell or they may be glazed and slipping.

 

[Rocfrog]

Just a small update this is what he emailed me yesterday....

and just an FYI the truck even though it is several years old it is brand new he has only assembled it and did the inital break in no other running has happened.....

it's not the slipper clutch it's practiclly brand new, it's not the flywheel, it's like hard clamped to the crankshaft. I haven't tryed retuning it or scuffing the clutch shoes.