prop driver removel rcv 120sp
 

How the heck do you get the prop driver (hub) off the collet with out destroying any thing. thanks

RE: prop driver removel rcv 120sp
 

I'm not sure what exactly your asking. The Prop shaft and backing plate are all one unit on the sp's. Maybe a pic to clarify?.

grinder.

RE: prop driver removel rcv 120sp
 

the prop backing plate is what I need to remove. it is on a tapered collet which fits on the prop shaft. I need to pull the prop backing and the collet off the prop shaft so I can get at the bearing and remove it. since it is a tapered collet, It is a press like fit. I need to use some sort of puller to get behind the prop hub and pull it straight off. I guess my question is what can I use as a puller without bending the fins on the prop backing. I hope that's a little more descriptive. thanks

RE: prop driver removel rcv 120sp
 

Hmmm tough one. I looked at my 90sp and see what your saying. My first response would be just ship it back to rcv and let them deal with it. Second option would be to make your own custom pulley remover. Something like, bear with me a piece of steal mounted on the prop shaft say about 6" long kinda like a fake prop with a jam nut. Holes drilled for 2 bolts to pass through one on each side of the prop shaft. A second peice of steel mounted behind the prop back plate with the bolts attached to it. Then all you have to do is tighten down the bolts and it should pull the back plate off. Here's the trick you don't want to pull on the fins so the piece of steel that goes behind the back plate must be cut to cover as much area of the back plate as possible to spread the load. Make sense?. If it was me i'd just send it to RCV.

Grinder.

RE: prop driver removel rcv 120sp
 

Thanks for the idea. I think I can rig something up, but like you said I may be better off sending it to RCV. Thanks again.

RE: prop driver removel rcv 120sp
 

Bugerdup,

Were you able to get the prop driver off your 90 SP? If so how did you do it and what did you use?

I have a 90 SP and it feels like there is dirt in the Cylinder housing assembly or bad bearings. When I turn the cylinder shaft (cylinder housing removed from crank case) I feel it drag in spots while I turn it 360 degrees.

Thanks

RE: prop driver removel rcv 120sp
 

OK - I figured it out but only for the Cylinder housing bearings so far. I don't need to replace the crank bearings yet.

Follow at your own risk and amend as needed.

Tools:
+ You will need the Allen wrenches to remove the Allen head screws from the Cylinder and carb.
+ You will need a small pulley puller. You can purchase a two fingered puller from an auto parts store for as little as $7.00 US. I used a three fingered puller.
+ Small metal that you can grind that is about 2 mm thick used to fill the gaps in the fins around the Prop Driver. You may want to grind the metal to fit the curvature of the Prop Driver. This is to keep the fins on the prop driver from bending permanently by the puller.
+ Propane torch used to heat the Cylinder housing and Prop driver to expand the aluminum from around the steal shaft and bearings.
+ Gloves to protect from the heat.
+ Wood Dowel to remove the front bearing and a small hammer. It should be a little larger that the ID of the bearing but smaller than the OD of the bearing.
+ Safety Glasses.

Step by Step:

First - Dismantle the engine down to the Cylinder housing. Remove the carburetor and the Oring at the base as well the the exhaust pipe.

Second - Place the metal you shaped above into the fins around the Prop Driver and adjust to fit.

Third - Test fit the fingers of your puller to make sure it fits between the bottom fin of the prop driver and the top fin of the cylinder. If the fingers do not fit then you may be able to grind them down a bit so they fit. They only need to just fit. You don't need a lot of extra space.

Fourth - Install the puller and start to tighten. Tighten it to where it is fairly snug. Watch the Prop Driver to be sure you are not bending any of the fins.

Fifth - Stand the housing vertical and apply just a little heat around the top of the Prop Driver. Rotate the shaft or turn the cylinder as you apply the heat to get it evenly heated. After I applied heat around the top of the perimeter of the Prop Driver it simply popped off. The Cylinder Shaft fell right out of the cylinder housing. Apparently the collet pressed into the Prop Driver were the only things holding the shaft in place.

Sixth - Remove the front bearing. Take the wood dowel and the small hammer and knock the front bearing out of the cylinder housing from the inside. The RCV90SP Exploded Parts View shows a snap ring holding the bearing but my engine did not have a snap ring so I assume they modified the cylinder and removed the snap ring from the design. If yours has the snap ring you will need to remove it first.

Seventh - To remove the rear bearing I drilled a hole in a 2 X 6 wood board just a little bit larger than the size of the end of cylinder shaft gear. I set the cylinder housing over the hole in the 2 X 6 and using my torch I heated the perimeter of the housing where the rear bearing was. I then just picked the housing up with gloves and set it down hard over the hole in the 2 X 6. The inertia caused the bearing to simply fall out of the housing and down into the hole in the 2 X 6.

Last - Find replacement bearings. I am now on the hunt for some good stainless steal with ceramic ball bearings. I replaced the bearings in one of my OS 46 AX engines a few years ago using stainless with ceramic ball bearings and it still feels as good as it did when I first installed them.

I am also using carb cleaner to clean up the case and parts.

Once you have everything you need make sure you remove the metal from the Prop Driver you used to keep it from bending. Reassemble in reverse order.

To see how to knock a bearing out using heat search YouTube. There is a two part presentation there by xjet on how to replace bearings in a normal ABC RC engine.

[link=http://www.youtube.com/watch?v=TuzEco3EDUM]Part 1[/link]

[link=http://www.youtube.com/watch?v=OLSoXPLGzOI]Part 2[/link]