Taylorm

Guys, i can't get the rear bearing out of my mega .21......i put it on a hot plate and got the case to about 300 degrees and it still wont come out......any ideas short of putting it in the oven???.or buying special tools???...........

asw7576

Special tools.

Riketsu

iTrader: (34)

300 Degrees what? 300F or 300C? If its 300F your still way too short. If its 300C, then your doing something wrong. Try putting it in an oven and wait till it reaches atleast 450-500F. Make sure to do this without the carb or the orings will melt.

After you get it that high, wait for atleast one minute till the entire engines reaches that temperature. Afterwards using some heat gloves take the engine out and tap it against something hard (usually the floor) and it will come out.

Taylorm

Nevermin, got it out today....put engine on a hot plate with motor mounts still on.....let it get to about 250..then hit it with a propane torch to about 400 degrees..the bearing plopped right out.........

Riketsu

iTrader: (34)

Congrats... Careful with those propane torches. I have seen bearings melt with em.

lil-bump

iTrader: (89)

Make sure when you re-install the bearing; only heat the outside case of the engine. If you heat the bearing directly you probally will melt the bearing races.

Taylorm

......first you put the bearings in the freezer for 24 hours in a ziploc bag to shrik 'em ever so slightly then heat the case.....they SHOULD pop right in.....

Paulie Bee

iTrader: (2)

After many years of torches, heat guns, presses and freezers, here is your only real correct answer: go to A main hobbies.com if they still have in stock and invest in this. You will thank me later. Paulie B.
1 x GRP Engine Tooling System Kit (.21/.28) (LOSR0050) = $169.99

M7H

As mentioned, 300 degrees is not enough, 400 you need atleast....
I always do it this way:
http://www.rbproducts.com/mainEn.php...ncept%20engine

Only instead of a electric plate, I put the engine in the oven, without carb and without any rubber seals in it.
At the same time, I put the crank with bearings as shown in the picture in the freezer, not for 24 hours but as long as it takes to heat up the crankcase...
I don't believe in using a tool to reinstall bearings by force, because it will damage the crankcase and after the 2nd or 3rd set of bearings, they might not be installed tight enough anymore....
But again, this is my feeling, not backed up by proof...

Taylorm

......absolutely unnecessary........tonight i heated the crancase to close to 300 degrees on a hot plate, removed bearings from a 24 hour freeze and they slid in like bearings slide into a plastic hub carrier.......no tools needed..........

fulcrum2

Does anybody know if the GRP Engine Tooling System Kit (.21/.28) (LOSR0050) works only with one main bearing size or all known internal diameters 13.5 / 14 /14.5mm?

Thanks, Stefan

Roelof

If you want a most universal bearing tool set I think the R&B is the best choice. It does support 13mm, 14mm and 14.2mm and since the C9 is using 14.5mm I expect there will be an 14.5mm piece as well.

TommyBlazin

iTrader: (29)

roelof,

have you seen the c9 yet? how does it compare?

Roelof

I have seen one and I was not impressed, later I was told he was using the wrong exhaust. From what I have seen (with the wrong exhaust) was that the motor was smooth, did not make any misfire (not picking up to rich ot to lean) but it did not show real power.