GL1100 final drive

[chewy999]

As the project continues and plans change, I wanted to strip the final drive down to clean it up and get the casing powder coated. I have managed to source most of the o rings and oil seals, which has been a challenge in itself, but then the haynes manual suggests that it is not really a diy job. Has anyone out there stripped their final drive down, and have any tips, photos etc, or should I leave it alone?
Jon :beg:

 

[slabghost]

I haven't done it myself but I'm not fond of the haynes manuals advice either. I think it is quite possible DITY. I can't recall a write up but maybe someone has done it. More will soon be answering.

 

[chewy999]

Got a couple of manuals, but I think the haynes manual is a good start, until you get to the dreaded 'reassemble in reverse order' phrase. The workshop manual is more detailed, but sometimes can cross refer to many times. I once stripped a Suzuki GS750 right down using a Haynes.

And I only had a small bag of nuts and washers left over! :rocks:

 

[joedrum]

every backyard machanic measure what left over and what got lost :builder: :mrgreen:

 

[dan filipi]

every backyard machanic measure what left over and what got lost :builder: :mrgreen:

Aint that the truth!

 

[scdmarx]

I think the Honda service manual had everything I needed to know. My 82 was leaking so bad, I tore it down and was able to get enough new seals to put it back together. I don't remember what they cost, but I'm thinking it was around $50. The problem was finding the new bearings. I shopped all over, and could only find them from an outlet we have here locally, who would have to order them individually by measurements. All the numbers were useless. But I could not locate the inner pinion bearing, which was in the worst condition of all. I could not find a pinion seal either, but thought I could reuse the old one if need be. The bearings I could order would cost about $350-$400. The pinion bearing being in the shape it was in, I saw no sense in putting it back together that way. At the time the units were available on ebay for $20-$50 used.

Inner pinion bearing race.

 

[82a]

haven't come across any diy info, other than some seals

even if able to take it apart and put it back together, haven't seen any info about setting up critical lash settings, or even anyone that does it

 

[scdmarx]

gallery/album.php?album_id=1156

 

[chewy999]

Thanks for the replies and info from scdmarx, but has anyone actually done the work? There is mention of critical settings, but if you put it back as it was, wouldn't that surffice?
Jon

 

[joedrum]

i just havnt done it ...but yes im sure it can done

 

[dan filipi]

I have tried adjusting ring and pinion clearance on pickup truck axles. It is tricky.
It takes the right equipment and shims to get it right or the gears won't mesh properly which will wear the gears fast and trash the bearings.
Before tearing it down, call around to some transmission shops and drive axle shops. They may be able to adjust it for you.

 

[Steve83]

I tore my '83 down, knowing I wouldn't be using it. The splines on the ring gear hub were almost worn away due to a bad rear wheel hub.

Mine didn't have any shims in it for backlash and tooth contact adjustments, but the parts catalog shows them. The bearing preload is adjustable for both ring and pinion.

You will need the right tools to remove the bearing races from the housing, but otherwise, it comes apart pretty easily.

They are cheap on Ebay. Just know that the '82 and '83 use a different gear ratio then the '80 and '81, but they'll all work.

 

[joedrum]

good stuff im not sure abiut being different gearing in the 1100 finals ...its just in 82-83 they went to a smaller rim ....and this is where honda makes it data from ...instead of at the finaldrive unit ....now there is difference in the swingarms and driveshaft size and sleeve ...to accomidate the smaller wider tyre of the 83-83 yr ....but finals the same ...so any 1100 final will work

 

[chewy999]

That's all food for thought, maybe that's why all the seals and o rings are so hard to get. Honda didn't think anyone would be dumb enough to try!

:thanks:

 

[scdmarx]

I used my pilot bearing puller to remove the bearing races. It looks to me like going back together is pretty straight forward. I don't remember being afraid of it. I remember thinking I could get around all the special tools. I've always used a torque wrench to check preload. There are specs listed for preloads, but the point of measurement is different. So a fish scale would likely get you close enough. Also, if you measure preload with a torque wrench before disassembly, that should get you pretty close as well. But doing it that way I think I would go back together just a smidge tighter. Be sure to check the backlash before staking everything down.
The preload of the pinion is to get the bearing clearance tight. There is tremendous side loading going on there during acceleration. It would take shims to set the depth of the ring gear. Mine didn't have any shims, so maybe they weren't required? Maybe the housing was properly machined and it was a good fit without any shims? But common sense, you'd want to peek at the ring gear depth to make sure the teeth are not bottoming out. My guess is it would be ok if going back together with the same parts. The ring and pinion are going to be a matched set, so you can't just replace one gear and not the other. But if replacing the housing, or going back together with new bearings, then that's what will change your settings. :moped:

The pinion bearing was the one I needed most, and was unable to find anywhere. And I got all the seals except the pinion seal. You won't know what bearings you might need, or not, until you get it apart.

Aside from having to get a little creative about working around special tools, the job looked straight forward to me. I've done quite a few automotive differentials and this one looked pretty simple. It ain't noth'n but some gears, and this one only has 2. I would say don't let this thing intimidate you. But you might easily be money ahead to just find a good used unit to swap out. And if all you're doing is chasing leaky seals, it may be even cheaper and easier yet.

 

[Steve83]

They changed the gearing slightly in '82 and '83. All 1100 final drives will physically interchange.

As I'm putting together my '83, I'm debating what gears to use. I have an '80 and an '83 final drive, and an '80, '82 and '83 engine to experiment with. Lower cruising RPM is nice, but more rear wheel torque is also a good thing.

Anyway, take yours apart, and if the bearings are decent and the gears are good, it should go right back together. As said earlier, use a fish scale to adjust the preload. Pull the flange out of the rear rim to hook it to for the ring gear measurement. A wrench on the pinion nut will work for the pinion setting.

Whatever you do, good luck with it! Post a pic of the results.

 

[dan filipi]

If it helps at all to decide, I noticed very little if any rpm difference between an 81 and an 83 final drive when I did the swap.

 

[Steve83]

Yeah, not much difference between 3.091 and 3.1

 

[dan filipi]

This is all good info even though chewy's original post was about stripping it down to have the shell powder coated.

 

[82a]

As the project continues and plans change, I wanted to strip the final drive down to clean it up and get the casing powder coated.

lotsa folks just spray paint it