LST2 Clutch and CB problems

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Brusselly

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HI

I have a new LST2 and manged to get about 15 minutes out of it before I had problems. It started with the clutch shoes jamming up inside the bell housing. Pulled the housing off and removed chunks of clutch, replaced with new Losi Aluminium clutch. Problem now is that the car wont drive. I've spent quite a while looking into it and can confirm the following:

- When I turn the 1st gear cog it turns the transmission via the slipper clutch, and this transimitted to the wheels, therefore assume tranny and diffs are OK.
- Roughed up inside of bell-housing and there is some scuffing on new clutch shoes, mainly on the elbow section.
-CB housing spins freely
-clutch shoes ahve been installed as per operating manual (ie thin side of clutch flush against the flywheel.

This is the really strange thing that I dont understand:
- when the engine is going the CB spins (clockwise) BUT in the opposite direction to the flywheel (counter clockwise). Defies my understanding. Every now and then, either going up or coming down in revs, the CB will start spinning in the same direction as the flywheel and hey -presto the car moves, though this is infequent and inconsistent.

Any ideas??
 
The CB spinning the opposite way of the flywheel is quite common as long as the truck is idling. The vibration of the engine running causes that.

Try putting the truck up on blocks, and giving it a little throttle input. Then you can tell if it indeed spins the CB and the 1st gear spur. If the CB spins but the spur does not, you have an issue with your clutch. If the CB spins but not the spur, take of the 1st gear OWB, clean it with DA and lube it with some OWB oil(serpent makes some).

Also make sure the CB is clean on the inside. When I first got my truck the CB bearings leaked some oil in the CB making it slip.
 
Thanks for the post. Its not just in idle when the CB spins in opposite direction to the flywheel, even at high revs it spins the CB clockwise and the 1st gear counterclockwise at high speed. Inside of the CB is clean and I also roughed it up a bit with sandpaper. Out of curiousity what does OWB stand for? Perhaps I'm missing something simple, could you confirm which direction the 1st gear should be spinning to supply rotation to the slipper cage. I'm assuming it needs to be spinning clockwise, because when I'm manually rotating the gear clockwise it propels the wheels.
 
OWB=One Way Bearing. It's what makes it possible for 1st gear to allow 2nd gear to propel the wheels.

Your problem could be the clutch shoes hanging up and not engaging at all, or maybe your engine is running in reverse. That can happen.

I suggest you start inspecting the clutch. Maybe even snap a few pics for us to investigate further.
 
I took the CB off the fly-wheel and ran the engine, its definitely running counter clockwise (when looking directly at the flywheel), which I assume is in the correct direction. I am confident about the direction its spinning because the clutch shoes were flicking out.
What to do?

PS: Starter cranks engine(flywheel) counter-clockwise (when looking at flywheel face on). Should it be cranking the flywheel clockwise? Should the cranking direction and running direction of the engine be different? The OWB on the crankshaft only lets the starter crank it in this direction.
 
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No... engine runs counter-clockwise. I said that once before... maybe you missed it?

The engine runs counter which spins the spur clockwise.
 
No... engine runs counter-clockwise. I said that once before... maybe you missed it?

The engine runs counter which spins the spur clockwise.
No didnt miss it, I said the engine runs counter clockwise. I was trying to work out if there was an issue with the starter turning direction, though I've discovered this is not the case.

I've still got the issue of the bellhousing turning clockwise. Does anyone know if the clutch shoes will flick out if, somehow, the engine was running in reverse? The only reasonable idea I can come up with is that when I accelerate the engine from idle it starts running in reverse....?
 
Are you certain it does it when you apply throttle? Mine, for some reason, at idle does what yours is doing, but as soon as I apply throttle, it spins the right direction.

I've had engines with pull-starts run in reverse before, but only a couple times and when it was cooler out. They would start in reverse due to the equivalent to a back fire when starting. I know it should be impossible due to the OWB, but this has happened to me on engines that had a OWB that was slipping quite a bit in the pull-start.

If you look at your starter shaft, or where it goes into the back of the engine, is it also spinning? If it is, which direction? The direction you turn it to start it or the other direction? You could be running into a similar problem.
 
Are you certain it does it when you apply throttle? Mine, for some reason, at idle does what yours is doing, but as soon as I apply throttle, it spins the right direction.

I've had engines with pull-starts run in reverse before, but only a couple times and when it was cooler out. They would start in reverse due to the equivalent to a back fire when starting. I know it should be impossible due to the OWB, but this has happened to me on engines that had a OWB that was slipping quite a bit in the pull-start.

If you look at your starter shaft, or where it goes into the back of the engine, is it also spinning? If it is, which direction? The direction you turn it to start it or the other direction? You could be running into a similar problem.
Yep sure does. On one occassion the fuel ran out and the engine was at the top of its revs spinning the CB housing like crazy clcokwise and the 1st gear spur counter clockwise at the same rate - while the car just sat there.
Apparently the engine running in reverse is common with nitro plane starting, someone posted that all he had to do was "burp" the engine to get it spinning in the right direction (whatever that means). I'm not convinced that the clutch shoes would flick out (leading edge) if the engine was running in reverse, has anyone experimented with putting their shoes on backwards before? Do they engage the CB in this position?

Good idea about the starter shaft I'll give that a look in. Have you any tips to work out which direction its turning, I find it hard to tell on smaller components when the engines on, its all a blur? I'll try to get some video footage which I can post to Youtube, could help with the diagnosis.
 
Ok... which way does your starter turn the engine? In reference to the engine from the back of the engine? CW or CCW?

Plane engines and bump start engines can be started in reverse easily by the power source turning the engine over being backwards. If the plane dude plugs his bananna clips in backwards to his hand starter, or if the bump start guy has his buggy on the starter box backwards...

For a pull/shaft start engine with a OWB, starting them in reverse isn't as easy... unless your OWB is put together the wrong way and your turning the engine over the wrong way or of it's slipping really badly (like mine) and backfires.

What are you using to start the engine? Drill or losi's spin start thing?
 
I think I,ve got passed the clutch, engine problems. The CB and spur gear are spinning in the right direction. The wheels, however are only getting power now and then. Attached is link to youtube
.(look at black mark on left wheel rim to get an idea of revolutions)

I can get the wheels to turn slowly at low revs, but giving it more throttle just spins the spur gear and not the wheels. Every now and then (usually coming down in revs) the something grabs and turns the wheels faster. The slipper clutch is on good nick, I even roughed them up. Slipper nut is screwed in full, minus half a turn. Centre diff problems? If i turn the spur by hand the wheels move.
 
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Could be your OWB on your transmission input shaft. 1st gear runs on a OWB. When it spins fast enough, your 2nd gear clutch engages and the first gear just spins on the OWB. But until 2nd gear kicks in, the OWB for first gear is supposed to catch and transfer the power to the trans.

There isn't a center diff on the LST.
 
I had a similar problem with my AS. I would get power to the wheels at low revs, but as soon as I put in some throttle the wheels would freespin, then they would engage again when the reves dropped. it ended up being the OWB in the spur gears. take a paper towel and twist it up so you can slide it in the bearing. turn it both ways and pull it in and out until it comes out clean. unfortunatly I still ran into this problem after about every tank and 1/2. but it worked as a temp fix until I bought a new spur setup.
 
Thanks I'll give that a shot. Already tried the transmitter settings in case the servo was causing the transmission to sit in neutral - no change.
 
Just to close this one off I fitted a new OWB to the spur gears and the car now moves under power. Its not 100% yet not sure its changing into 2nd gear or getting all the power to the wheels. Will suss it out a bit more and start a new post if need be. Thanks for all the help, breaking your new toy first up is certainly a good way to learn how everything works.
 
You could have a grub screw on either one of the trans outputs loose and that would give you the simtoms u,ve described!!!Also check the inputs into the diffs!!!;)
 
Oakster I believe you are right, this is a common issue with I know for sure the aftershock, Ramminator and Mega Baja. I have a ramminator, and if I'm not mistaken it actually tells you in the little start up sheet that comes in the box that you have to loctite those grub screws in your tranny. A friend of mine did not do this and his did the exact same thing as your describing in about 5 tanks. I think you will find this to be your problem. It also says to loctite the grub screws on your outer CV shaft pins, mine fell out on the 2nd tank, just doing slow circles!!
 
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