Hi, I want to pull fourth gear out of my 2000 manual gearbox. I've got a puller on it and I'm putting alot of pressure on it and it's not budging. Should I keep winding the puller? Or does the shaft dismantle from the other (overdrive) end?

You're right, the output shaft dismantles from the other end. You'll notice the final drive gear is part of the output shaft, it can't be pulled off. There's a fair bit of dismantling for you, remove fifth gear set, remove selector block and push the two shafts out.

Thankyou Vic for your quick reply. As you can just see in the photo, the teeth are ripped off the final drive, since the oil leaked out the selector shaft seal, and the roller bearing failed, leaving the output shaft free to bounce. I was hoping as a long shot that I could replace the 4th gear set as everything else seems ok. But since 4th gear *is* the shaft as you say, I guess that means a complete gear box replacement?

I see fourth is shot but the final drive pinion on top of fourth looks okay to me meaning the output shaft could be used again as long as there's no teeth chipped or missing on the output pinion. I have spare gears and shafts if you wanted to try and fix it. Sometimes its cheaper to find another gearbox though.

Edited 28 December, 201312 yr by Vic

go on clubg40 in the transmission faq theres a guide to the stripdown

Thankyou for your replies, most helpful. One last question. Above the final drive gear is the inner race of the roller bearing. I started grinding this off so I could get a look at what was stopping me pulling the gears. It's on the other side, not in view. Is the inner race a VW gearbox part or will it be supplied as part of the new bearing by say SKF?

Your new bearing will have a new outer race. Its practically a rear wheel bearing, taper roller. Useful tip for removing the outer race in the other half of the box is to run a bead of weld around the race, it will shrink the race and drop out. Unless you have a blind puller of course.

You'll also find a shim under the old race, ideally the shaft should be reshimmed after you change the bearings for correct bearing preload, but some have reused the old shim.

Edited 28 December, 201312 yr by Vic

The outer race and shim just fell out from damage. It's the inner race on the shaft that I've damaged with a grinder.

I made a custom expanding tool to get the 5th gear circlip off. Now I'm in the process of sourcing a kukko20/10 puller to get the 5th gears off or see if I can make something.

At this stage I know I'll need at least: a pair of 4th gears, output bearing including inner/outer races, and a new selector oil seal; to avoid a complete gearbox (which may end up being cheaper).

5th gears removed with adhoc tools

A home made circlip expander

A home made puller from scrap. 8mm threaded bolt fits shaft.

Next, a custom puller to extract the selector shaft plug. A nasty 7mm thread at "Pull sealing plugs out" in:

http://workshop-manuals.com/volkswagen/polo-mk3/power_transmission/5-speed_manual_gearbox_085/gearbox_mechanicsoperation_constructiondiff./dismantling_and_assembling_gearbox/dismantling_and_assembling_sequence/

It's finally out. Here you can see the damage to the fourth gear teeth when the shaft bounced around after the end taper bearing disintegrated. Also here is the damage I did to the inner race with a grinder trying to get it off.

If the final drive is part of the shaft then there seems to be almost no leverage point to remove the inner race. Will I be able to replace fourth gear and the inner race?

Ah, I see in the workshop manuals that the inner race does come off, but with a special gripper tool.

Figure 5

http://workshop-manuals.com/volkswagen/polo-mk3/power_transmission/5-speed_manual_gearbox_085/gearboxmechanicsgearsshaftsinternal_operation/dismantling_and_assembling_output_shaft/

Do I dare to keep grinding. If I keep removing tiny bit by bit I must get through the ring and not damage the shaft.

I would be checking your gearbox casings for cracks mate if that's the damage you have due to the bearing. I've split boxes with less damage to the teeth and the box was full of hairline cracks around the bearings

Thanks for the advice. There's some scratching of the case but no cracks.

My mechanic pressed off first gear with a hydraulic press, and air chiselled off the bearing inner race (far left).

In theory I'm just one circlip from removing 2nd, 3rd and 4th.

Well, I had to go back to my mechanic to press 2nd gear off. He did it for free again so I paid him in beer. I've got 3rd off and now finally 4th.

My local VW dealer quoted $1238 for a pair of 4th gears. I'm getting them from one-stop-gearbox-shop on ebay for $305 including airmail to the other side of the globe. In the meantime, lots of degreasing and cleaning of the case and parts.

4th gears and seals arrived. This polo rear wheel bearing kit supplied the 29mm/50mm (ID/OD) bearing for the gearbox since I couldn't find out if the gearbox bearing kits were going to supply a 26.9mm (std) or 29mm bearing (6N2 variation). More pressings by my local mechanic and more beer as payment.

During assembly the output shaft needs adjusting for the right play/preload by changing shims. Unfortunately the shims are behind the outer race embedded in the casing. A 45mm blind puller is about $165 plus the $200+ slide hammer. My home made blind puller (on a mini-lathe):

The gearbox is finally all back together. About $400 in gears,seals,bearing,oil and a lot of labour, but cheaper and more fun than a second hand gearbox ($1450 in Aus). Thanks for your help.

Have a look at this http://www.clubpolo.co.uk/forum/index.php?showtopic=315921&hl=gearbox there are all the instructions on strip/rebuild of the 085 box