Scooterotica

Evening peeps,

Just gave up on the building of an engine that I have been on the whole afternoon. Late Lince casing. Original bearing. Original gears. New needle bearings. All spacers in position. Rear axle fitted well on the bearing. Fitted original shim. Fitted endplate with a new 6004 on it. The usual 1, 4, 6, 3, 5, 2 procedure for closing. Fitted the spider for testing and OK.. well... a bit hard. Could turn the shim a bit with my finger not to much. Fitted a lot of gear oil to lubricate things well. Then fitted the hub............ Problems. After locking the nut, the hub becomes rock hard. Then it turns a little, then it turns loose for half a turn, then hard again. No way of moving it.... Even if I try.

I must say that I got the engine with just the gearbox on. The endplate looked like it was the original one. Any thoughts any one?

Regards,

Jaime

Do you have brake shoes in it? if so then might be them.

Im actually trying it without any brakeshoes on...

process of elimination realy. Take hub off first, and try and turn layshaft. if not that then put back on and take another part off and try again etc. Russell

is the new bearing fully home?

Needs checking and then checking gap with hub tightened fully first

Chris

As suggested I would be inclined to check that the shaft rotated ok with no hub fitted , if all seems ok then fit the hub if it went tight then the problem would seem to be related to the hub. Possilble causes wrong hub cone causing hub to bottom out on brake shoe lip. damaged brake shoe lip hitting hub. buckled hub. If you still cannot find the reason find some sort of spacer to replace the hub, use a rear suspension nut ( no nyloc to make it stiff) do it up and check for rotation it should be ok, if not problem is inside gear box area . I always use this spacer system when building the gear box end to ensure that things are in the right place when i am doing the end plate shims. If there is a problem remove the loose gears and try again ,elimination is the only way.
Best of luck.
Keith.

Definately shim it with a spacer as the hub . I shim loose gears with out the mainshaft fitted, makes life a lot easier when you have to remove endplate a few times. Then attach hub and torque. If the hub sticks, then it's the hub. If it is not the hub, not the shimming, then when you put the mainshaft in, you may find the loose gears and cluster gears don't mate correctly Trail and elimnation, as said before.
It is my belief you don't have to fully torque to 120ft/lbs for shimming. That torque only locks the hub to the cone, the axle can be drawn into the rear hub bearing with a lot less torque.
A small piece of steel rod inserted into the selector ball holes(before gear selector is fitted) that rests against the inside of the casing, can be used to stop the axle from turning when tightening up the axle for shimming.
Excuse me for what may seem like a repost of what Vince said, but I think the shimming with an empty box and not needing 120ft/lbs when shimming is an important consideration.
It might could be the little lip on the case that runs in the groove of the hub is interefering with the hub movement also.

WOW! I am overwhelmed by the responses. Thank you lads thank you really! I am going back to the workshop right now! Be back with news soon!!

Jaime

Ok just got back from the shop... Well the problem is somehow sorted but I am still having my doubts it is.

I tried what Mr. Lopez, suggested with the long rod on the layshaft and fitted an old main bearing as a spacer, it fits and does the job perfectly. Tried the spacer and got the shimming correct. So layshaft and shim are out of suspicion. Next thing, tried fitting the gearbox and the endplate. When I propperly adjust the screws on the endplate I can still turn the shim without problems. Then I fitted the crown and the spider to perform the ending test and... The spider turns, with difficulty (as the spider always turns a bit hard) but it gets stuck at a point and I have to force it through that point. Then gets on with ease and I have to force it through that point again.... (On neutral, the rear axle turns fine) Any ideas?

try another endplate