Final Drive Surgery with Pics

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BinDerSmokDat
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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Wed May 15, 2019 1:49 pm

I really don't want to have to Dremel the inner race.
Even with a small cutting wheel it is difficult to cut the race without cutting the wall of the driven hub.
There is no way to get any kind of puller to grab the race, but a Google search came up with this neat trick.

I'm going to try it tonight.
Basically you weld a bead inside of the race.
When the bead cools and contracts, the race falls out of the hub.
Fingers crossed.

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Re: Final Drive Surgery with Pics

Post by rougaroo » Wed May 15, 2019 2:06 pm

I read back through the thread and can't figure out which race you're talking about. Which race are you having trouble removing?

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2003 Tourist - lotsa upgrades
2004 Troyka - work in progress

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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Wed May 15, 2019 9:10 pm

rougaroo wrote:
Wed May 15, 2019 2:06 pm
I read back through the thread and can't figure out which race you're talking about. Which race are you having trouble removing?
Last year while working on the sidecar wheel bearing I dropped the 2WD shaft on the 2010 FD and the ball cage of this bearing popped out...

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The cage was broken and the balls and inner race weren't being held in by anything.

So instead of taking it apart (I had a ride coming up) I threw my 2005 "spare" FD on the bike.
When the 2005 FD blew up last week, I had to get off my lazy a$$ and fix the 2010 FD as it was a quicker fix than rebuilding the 2005.

There is no way to get behind the bearing and tap it out from the spline end.
My thought was to weld a bar of steel or a washer over the race and then use that to tap out the race.

I didn't have to do that, I'm happy to announce that the above "welding inside the race trick" worked.
However in the link they use a MIG welder and I only have a cheap flux core.
This led to a little weld splatter and some BB's I had to clean off the drive hub.

Next time I'll shove a wet rag in the hole and wipe some nozzle paste on the edge of the hub.

I'm busy getting ready for the Jersey devil Hunt this Thursday, I'll post pics when I can.
I'll also detail the rebuild of the 2005 FD as I go.

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Re: Final Drive Surgery with Pics

Post by rougaroo » Wed May 15, 2019 9:33 pm

Depending on whether you have a welder or not and how many times you might run into something like that race, there's this or similar. I don't have a welder, so went with this:
https://www.harborfreight.com/slide-ham ... 62601.html

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I've used it for the race in the triple tree, the FD, etc. Yeah, it sits unused for a long time, but when you need it it does the trick.

There are different sized internal tools with sharp flanges to grab the edge of the race. You screw in the bolt end, expanding the flanges against the race. Once you have a purchase, even a small one, you use the slide hammer to pop the race out.

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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Wed May 29, 2019 10:58 am

rougaroo wrote:
Wed May 15, 2019 9:33 pm
...I don't have a welder, so went with this...
That isn't going to work; I tried. :(
The bearing race fits against a machined lip inside the splined hub.
There is no gap or lip to catch the race.
The inside of the race is curved to hold two rows of ball bearings, so there is no lip there to get a purchase on.
If the bearing is intact, a puller or tapping it from behind with a socket and long extension/tommy bar will work as shown on Billy G's excellent page.

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If the bearing sh!t the bed and isn't intact, you need to Dremel the race or try the welding trick.

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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Fri Aug 21, 2020 12:49 pm

I have an issue in my FD which is my 2005 "spare", that caused some funky ring and pinion wear, with some chipped teeth, but not fully broken.
This weekend I'll be tearing it apart top rebuild it.

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Also, I have the original FD that I blew out the 2WD bearing in 2018, so I'll be rebuilding that as well. (I'm a procrastinator, what can I say? :oops:)
So while not as impressive as Chad's 5 engine rebuild, this 2 FD rebuild should provide some useful info and I can revisit my ideas on FD's from 2013.

I can also highlight the differences between a 2005 and 2010, the main being the different pinion nut/seal for the old style 2005 driveshaft and the new style 2010 driveshaft.
Currently I have to swap driveshafts when changing between the two FD's including dropping the swing arm.
I will rebuild the 2005 to take the 2010 yoke and driveshaft, so future swaps will be drop-in simple.

Also note that throughout the original rebuild I was referencing F A G bearings and due to a subsequent change to the forum language filter, these references were converted to "fig."
So no I'm not crazy and neither are you, when you see a reference to "fig bearings" know that it is brand name F A G.

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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Wed Aug 26, 2020 1:51 pm

I started my tear down and rebuild this weekend,here are some pics.

First, have a reasonably clean and tidy space.
It's not a terribly difficult job, but when you start misplacing parts, dropping things and generally losing track of stuff, it can get ugly.
That is especially true in my case with two different years of FD with slight, not readily apparent differences.
Some sort of overhead light is handy for reading tiny print on seals and finding all of those loose needle bearings.
You cell phone camera can act as a magnifying glass, as well as document the order parts were removed for later when it's time to rebuild.
Lava lamp and cyclone rocket lamp are more for general relaxing effect than illumination. :D

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Everything in this post is the 2005 FD.

Difference #1 between 2005 and 2010 FD.
The drain plug is non-magnetic.
I didn't have a spare magnetic drain plug at the time I put this into use on my bike.
I will upgrade to a magnetic plug when I rebuild.

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I won't document FD removal and brake pad removal here, you should know how to do that before you attempt an FD rebuild.
Here is the first seal that needs to be removed.
All of the 2005 seals were really hard to get out they were a tight fit.
I think they had swelled slightly and hardened.
I also found later that a shot of brake cleaner helped loosen up the thin layer of crud holding them in place.
I am replacing every seal in both FD's, so removing them intact is not a concern for me.
I used a screwdriver to pry it out but some pliers were also needed, as it was stubborn.

Note the little "bump" at the 11:30 position next to the rim that surrounds this seal.
The rim acts to catch oil and diverts it via a small weep hole through that "bump" to the other side of the plate.
This way the brake pads stay oil-free in the event you leak some oil at the seal.
At least that is the theory; that groove gets crudded up quickly, if you have a leak and then ride off-road or even on-road for long enough.
When ever you have the pusher wheel off, check that groove clean it out and make sure that hole is clear.

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Seal is out and the weep hole bump is now in the 6:30 position.
It is just about dead on with 6:00 position when installed on the bike, allowing it to drain completely.
As mentioned, the seal was trashed upon removal.

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With the seal out you can access the steel FD Case Sleeve.
Just the shiny rim of which is visible in the center of the hole.
It is NOT mandatory to remove this but I wanted to do a very thorough clean.
I was probably being overly nit-picky but I'm hoping this is my last set of FD rebuilds for a few years.

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Support the seal surface with a block of wood and using a hammer and punch, tap at 3, 6, 9 and 12 o'clock to drive it out.
Mine came out by time I got to 9 o'clock.

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As this FD died a while back, I had already performed some of the disassembly but didn't document it.
Here is the pinion hole, sans pinion.

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Interior of case.
Notice that there is a dark grey appearance to the aluminum in all of these pics.
Not sure if it is just age or change in alloy.
The 2010 aluminum case parts are all shinier and better machined and finished than the 2005 parts.

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Again, some partial disassembly had previously occurred so here is the driven splined hub and ring gear assembly.
Note the "Summer Teeth."*

(*Summer there, sum ain't.)

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Flip it over and you can see the retaining clips on the ring gear bolts.
I will be upgrading to hardened bolts and loctite on the rebuild.
The bolts were VERY LOOSE, several turning a 1/16th of a turn with barely finger pressure on the wrench.
I didn't even need to bend the clips back to remove them.
I just put a wrench on them and turned, they just pushed against the tabs and flattened 'em enough to let me take the bolts out.
once one bolt on a tab was out, i could get the box end ratchet on them and work them out quickly.
The ring gear was mounted firmly to the carrier and the clips did their job, so I don't think this contributed to the failure, but who knows.

Also note the weird pattern on the bolt heads. They look worn and if you look closely, it almost looks like a nut on a stud.
Not sure if the bolts had backed out at some pint and reused?
But there was no wear/damage in the case or to other parts and the metal tabs looked like they had only been used once.
Also the grinding was very clean and precise. Not what one would expect if bolts backed out.
Did the factory "clearance" some bolt heads with a grinder to make them fit the case?

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With the bolts out, invert the assembly, smack it on the table and the ring gear comes loose.
Note the steel and bronze washer.
Bronze is outside, steel on the inside.
The amount of material broken off is significant.
I will compare the 2005 breakage to the 2010 breakage later.

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Next up this seal needs to come out.
This one pried out carefully with a screwdriver, no problem.
This is also Difference #2 between 2005 and 2010.
This seal is a fractional MM seal marked "62-06162-10."
This seal is 24 X 36.5 X 8.
It was also used on older alternator adapters and wheel seals.
At some point in 2005 Ural moved away form the factional seals to standard sizes available anywhere.
The newer FD's use a 25x35x7 seal.
Apparently the difference between 24 and 25mm isn't crucial?
Or the 24 is overly snug and the 25mm just fits?
But the outer dimension IS crucial, the new type seal will not seal in the larger opening.
These older seals are available at Crawford's and other knowledgeable Ural parts houses.

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Just remembered Difference #3 that some eagle-eyed observers may have noticed.
The 2005 used nuts and lock washers on the M10x1.25 studs; the 2010 uses NyLok nuts.
I have ordered new NyLok nuts and will be using them for both FDs.

The smaller M8 studs used lock washers and nuts on the 2005.
The 2010 used a socket cap М8x30 8.8 ZN DIN 912 screw (I have to verify pitch)
If I can find them, I will upgrade these as well.
Having the different nuts/allen heads is also a good reminder not to undo all the nuts when dropping the FD or you end up with a mess. :lol:

More to come!

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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Thu Aug 27, 2020 9:38 am

Continuing with the 2005 tear down...

As mentioned before the 2005 FD was already partially disassembled before this, so the 2WD engagement coupler is already off of the 2WD splined hub in this pic.
You just pull the 2WD fork and the coupler moves to the end of the splined hub and slips off.
A couple of things to note here.
First there was a number written inside the case, at the 12 o'clock position.
I'm not sure if that is a "12" or a "21." Any guesses as to what it means? I have no idea.
It's funny that the number lasted for who knows how long inside the case with oil, but when wiped with a rag it came right off.

Next Difference #4 between 2005 and 2010.
There are two "pins" that sit in the holes in the ends of the forks.
They are technically removable on the 2010, but are a pressed fit, they don't come out easily.
On the 2005 they are a slip fit and fall right out when the coupler is removed.
The pins are a different shape, so not sure of the pins and slots are interchangeable.
I'll try to remember to look next time I'm working on it.
Anyway, the cotter pin located on the 2WD fork between the pivot and the splined hub needs to come out.
Get the needle nose pliers and slip it out...

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With the pin out you slide the pivot out of the top of the case and the 2WD fork comes right out.
This pic shows the pivot and fork assembled, laying on top of the case.
If you look at the tip of the uppermost fork arm, there is a small tab, that sticks out longer than the other arm.
This tab engages the ball detente sticking into the case at 11 o'clock, which holds the bike in 2WD

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Next a split ring holds the 2WD splined hub in the bearing.
The splined hub is inserted into the case from the outside and the ring keeps everything together.
Here is the view from outside the case.
Yes that bearing will be replaced.
I have bearings with rubber seals, so when I install the new bearing I will pull the seal exposed to the oil and leave the seal on the outside to help protect the bearing better.
The factory solution is that the o-ring on the 2WD yoke should seal that area but as you can see, that is less than ideal.

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Difference #5 between 2005 and 2010, the 2005 uses a split ring and the 2010 uses snap ring style circlip.
I found the split ring to be a bit harder to get off.
I used a pry bar and flat head screw driver to spread it then got a probe under the ring, then was able to pry it up, but bent the ring a little.
The shaft diameters, groove depth and width are the same, so I ordered some new snap rings and will replace both with new.

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I'm jumping ahead a little in the next pic, but here is the 2005 and 2010 clips side by side.
I prefer snap rings with holes, so much easier to remove and install.
As you can see, the split ring one is bent.

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Next set the case on your vise, so that the outer edge of the case is supported but the flange of the splined hub is free to drop out.
Put a chunk of wood on the splined hub and tap with a hammer.
The hub should drop out of the bearing.

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With the 2WD splined hub out, you can see the bearing in the outer case.

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Take a punch and hammer and tap around the bearing at 3, 6, 9 and 12 o'clock from the outside of the case.
Ideally you want to catch the outer race, but the seal is in the way so space is limited.
I'm sure there is some sort of bearing puller that would pull it out by the outer race but I have no such set-up.
I was hitting the inner race but this is a light press fit so my bearing dropped out easily after two taps.
This bearing was in good shape (note this is not the bearing pictured above) so I may reuse it.

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Then from the outside of the case, punch out the seal.
The spring popped out but this seal was in pretty good shape, and it wasn't leaking so could likely be reused, but I found a viton seal at a reasonable price so both cases will get new seals.

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With the case cover empty of parts, it gets a degreasing and I move on to the pinion gear.
The pinion gear takes ALL of the force of the engine and rides on two bearings, the needle bearing at the tip and the double row roller bearing (F A G 3304B.TVH) at the spline shaft.
I will repeat that for emphasis...every horsey your engine can muster, after being multiplied by the gearbox is putting force on these two bearings.
I recommend replacing BOTH of these bearings if the pinion is trashed.
If you have opened the case just to replace leaking seals and the FD is in otherwise good mechanical shape, you can leave these alone.

You can probably pull the double roller bearing intact with a bearing separator/puller, but if the pinion is trashed, you are likely trashing the bearing as well, so it doesn't matter how you remove it. Or even IF you remove it.
I only tapped the pinion out because I will keep the ring and pinion for comparison/reference/decoration and it stores easier without the bearing on it.
The roller bearing was pretty loose, as you can see the inner bearing race is still up against the teeth, after tapping the pinion out.

As for the needle bearing, my last one took a lot of force and heat to remove.
I don't know if the older ones were easier to remove, but as I said above, I believe if the pinion is trashed, the bearings should be replaced, so I'll be replacing mine.

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Set the 2WD splined hub in the vice so just the edges of the flange are supported and the bearing can drop out.
Then take your drive shaft and tap the bearing out.

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Then when the bearing comes out, but is stuck on the shaft, set the bearing on the vice and tap the shaft out. :lol:

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Next up, let's compare the breakage of the ring gears.
Below the 2010 gear is in the foreground and the 2005 is in the background.

I broke the 2010 on Bloody Skillet, a tough and challenging ATV/UTV trail that I later found out we probably shouldn't have been on.
I rode down the mountain a little ways on the damaged teeth before it was towed out.
The 2005 failed in the Pines, not even revving or stressing things.
I stopped almost immediately and ReCycled towed me out, after covering the FD spines with the dust cover so the pusher could freewheel.

The 2005 lost 3 full teeth, right down to the base of the cuts.
The 2010 lost 1 tooth and chipped two others, about 1.5-1.75 teeth in total.

This would seem to indicate that the ring gears have definitely gotten better.

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That's it for the 2005 FD, I'll be tackling the 2010 disassembly next.
Last edited by BinDerSmokDat on Thu Aug 27, 2020 9:51 am, edited 1 time in total.

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Re: Final Drive Surgery with Pics

Post by stagewex » Thu Aug 27, 2020 9:49 am

Nice work Rich.
You may have written it somewhere but when both are completed which will you install/which will be the “Spare”?
Stagewex

Current Herd all running amok:
2019 Honda CRF450L (Elec Start)
2008 Vespa 150S (Elec & Kick Start)
2007 Ural Patrol (2WD, Elec & Kick Start)
2006 Honda "Big Ruckus" PS250 (Elec Start)
1991 Honda XR250L (Kick Start Only) *NOT running amok, out for Bottom & Top-End Rebuild.
1986 Yamaha BW200ES (Elec & Kick Start)

List what you "have", keep the others in your precious memory bank.

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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Thu Aug 27, 2020 10:02 am

I honestly don't know yet.
When completed they will both be built to current modern Ural specs as far as new gear sets and almost all bearings and seals will be replaced with current factory recommendations or BETTER in a couple of cases.
Both will have the high strength ring gear bolts with high strength loctite.
From a mechanical standpoint, they will be almost identical, with the exception of the fractional seal I mentioned above and the drive shaft yoke, which I will address in an upcoming post.

It will likely come down to whichever one I have all the parts for first; some things are still in transit as of this writing.
The one I have all the pieces for first will likely be the one I finish rebuilding and put back in the bike.
Right now the rig is sitting on jack stands and I want to get the rear wheel back in before monkeying with some other stuff.

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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Fri Aug 28, 2020 9:11 am

Difference #6 between the 2005 and 2010 FD's.
The dipsticks.
The thread at the dipstick opening is the same, M14-1.5 on both and is the same as all drain plugs on the bike.

On the bottom is the 2005 dipstick.
Note that it has a little green o-ring AND a sealing washer. Not sure if that is the stock set-up or if someone added that, but I got it that way.
It also has a bigger nut with a plastic breather cap and the dipstick has no markings.

In the middle is the 2010 dipstick.
Smaller nut, uses an aluminum sealing washer only, markings on the dipstick.

Finally on top is a nylon NPT barbed fitting, alongside some clear Tygon tubing.
If you plan on water crossings or even the possibility of deep puddles is in your riding future, do this set-up.
I couldn't find a metric barbed fitting with the right threads so I bough the closest NPT in nylon (1/2"??) and I wrap it with teflon.
The teflon insures a solid seal and because it is nylon, I don't damage the threads in the FD.
(Some folks have recommended using a brass fitting but I feel that the threads would be at risk.)
The clear tube uses a small hose clamp to hold it on the barb and then it tucks up behind the rear break light support.
Use a long enough piece of tube so it can move with the suspension, but not too long that it can get caught in the spokes.

Some people have mentioned using an ATV bellows, especially on newer bikes, but I'd avoid that.
The reason is that the FD can get quite warm. When you hit water it cools suddenly and the warm air inside wants to contract.
This creates negative pressure or vacuum inside the FD case.
With the bellows there may or may not be enough volume in the bellows to completely eliminate any negative pressure/vacuum.
The case only needs to be slightly negative to then want to pull water in around any seals.
With the FD vented to atmosphere, it will NEVER be under negative pressure so it can never suck in water around seals.
It is also tucked up so high that your last worry will be the final drive if the water is as high as your rear brake light.

I keep the stock 2010 dipstick in my tool kit, so that I can check the level on the road if necessary.

Image

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Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Mon Aug 31, 2020 11:07 am

I actually started doing some assembly this weekend, but I'm behind in posting the disassembly stuff, so I'll try and catch up today...

All of this disassembly is on the 2010 FD.
I had been running the 2005 on the bike so had put the old-style drive fork on the bike.
When I had to swap the 2010 on, I put the old style 2005 drive shaft yoke on the 2010.
Remove wedge pin nut, tap out wedge pin and yank yoke off the pinion.
You may need to pry slightly on the flange on the yoke to pop it off.

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This brings us to Difference #7 between the 2005 and 2010 FDs.
The older style drive shaft yoke (on right with chrome driveshaft) has a smaller diameter on the collar that slips onto the pinion.
The pinion nuts are the same size threads and the O-ring is the same, but the inner diameter, the seal and yoke end are different.

Whichever unit I have completed 1st will be set-up with the new style-yoke and drive shaft set-up and I'll drop the swing arm and put the new style shaft back on the bike.

I will keep an eye out for a new-style yoke and slip shaft, so when I want to swap between FDs it is a drop-in affair.

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The outer case nuts have been removed when the FD is dropped, so just remove the two socket head cap screws that hold the case together.
Insert the rear axle into the case like this and tap it lightly with a hammer and the case will split open.

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Carefully lift off the outer case over a nice wide, clean surface as the splined hub needle bearings will be falling out.
Also be careful of the gaskets if you will try to reuse them.
I highly recommend replacing them given they are inexpensive.
If you were in a situation where you needed to put everything back together without access to spares, slip something like this thin plastic ruler under the gasket and move it side to side, freeing the gasket form sticking to the sealing surfaces.
Pry up gently near the studs to free the gasket.
Make sure you carefully free the gasket form the sealing surface and at every stud and you might just get it off in a usable shape in an emergency.

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Here I'm using a magnet to collect all of the splined hub needle bearings.
Make sure you find them all...there are 45 of them.

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The tab broke off my pinion nut wrench, so I'm using a pipe wrench.
Remember it's reverse thread, righty-loosey.
Careful application will remove the nut without damaging it.

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With the nut removed the pinion will slide right out.
Again, using the magnetic probe, fish out all of the needles.
Difference #8 between the 2005 and 2010 FDs...the older units have 28 needle bearings.
The newer FDs have 29 needle bearings.
If you order from a dealer with some NOS laying around you might get a 28 needle bearing.
The outer dimension of the races are the same, so you can use either on any pinion gear.

However use the right race with the right needles.
I would NOT mix needles or race from a 28 or 29 needle bearing.
The difference is small, but that extra needle has to fit somewhere so there must be a small difference.
If you try to put 29 needles in a 28 race, not sure they would fit.
Put 28 needles in a 29 race, you'd have slop.
I haven't mic'd the needles to see if they are the same size, I'll try to remember that for assembly.

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Again, I'm not reusing the pinion gear or bearing just punching the gear out of the bearing for ease of storage/display/reference.

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Back to the case, I pulled out the seal, it was leaking a little so I didn't care if I trashed it.

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Then you can use a punch and tap out the spline race.
It's isn't worn and I probably could have left it, but wanted to do a thorough cleaning.

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Next up, throw the spline hub in the vice with some blocks of wood.
Then grab you breaker bar and 13mm socket.
Remove all 8 bolts.
These were loc-tited when I rebuilt it in 2013 and took some effort.
The original bolts that I removed in 2013 took heat to break them.
Not sure why these broke loose easier.
Maybe the Russians used something stringer?
Or maybe I filled mine with oil right away and it didn't cure as strongly?
I will be using high strength and let it cure overnight before assembly this time.

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Here are the bolts.
Difference #9 between the 2005 and 2010 FDs.
The 2005 bolts are a smidge longer because they have to go through the locking tabs.
Not sure how long they are, didn't measure but the new bolts are М8x20 10.9 ZN DIN 933.
I'm guessing the old ones were M8x22 from the looks of them.
See previous disassembly of the 2005 above for pics of the locking tabs.
Both FDs will get new MBx20 bolts.
They are probably reusable, but why risk it?

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Detailed above and not depicted here...
-Pull the 2WD engagement coupler and 2WD fork forward, and slip the engagement coupler off the splines.
- Get your needle nose pliers and pull the cotter pin out of the 2WD fork pivot, then slip pivot out of case and remove fork.
-As mentioned above the 2010 has a circlip, not a split ring. Get your GOOD circlip pliers and remove it.
-Flip over case cover and tap the 2WD splined hub on the bench, pushing it out of the outer case.

Take the rear axle and use it to tap out the 2WD splined hub bearing.
make sure you have it set on the vice so that the flange of the hub is supported but the bearing can slip out.

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Go back to the outer case and using a punch from the outside, tap the bearing out.
This one was very gritty with rough spots when spun and it will be replaced.
Then tap out the big Viton case seal in the background.

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That concludes the disassembly of the 2010.
At this point I called it a night.

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Joined: Thu May 06, 2010 2:35 pm
Location: South Jersey NJTP exit 6

Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Mon Aug 31, 2020 12:01 pm

So after disassembly, all bearings were examined, almost all were discarded for either excessive slop, being gritty, or having inner races and/or balls falling out.
I'm reusing the large halo bearing that backs up the ring gear and the large outer case bearing from the 2005. They were was cleaned with brake cleaner.
All other bearings will be new.

Everything was pre-w@$#ed in water based degreaser, then sat in #2 heating oil and nylon brushed clean.
Some rough spots from rust or wear and scratches on sealing surfaces (I scratched some stuff removing bearings or seals) were smoothed out with 3m green pad.
Everything got a final rinse with acetone or brake cleaner.

With everything cleaned up, the splined drive hub teeth on the 2010 (left) are looking very pointy (bad).
The ones on the 2005 are still flat on top (good).

Hub spline teeth do not wear in a linear fashion; meaning once they get pointy they tend to wear faster.
There is less material to engage the other set of splines, so wear of BOTH sets of splines is accelerated.
If you let the drive hub get pointy, it will accelerate the wear of the wheel hub on it until the point either the hub or wheel splines fail.
If you rotate tires on the pusher, you are only spreading that accelerated wear around.
So it's up to you, replace the hub or keep rotating wheels until you have three worn wheels AND a worn hub, or replace the hub and slow the wear on the wheels.
As a result, I will be replacing the hub on the 2010.

Image

While I'm waiting for the new 2010 splined hub to arrive, I will most likely finish the 2005 FD first and install that in the bike.
I can do some sub-assembly work on the 2010 while waiting for parts.

I decided to go ahead and stamp the cases with their respective years.
Here are the outer cases, 2010 above and 2005 below.
(uggh I missed brushing/blasting that detente screw on the 05)

Image

Here are the other halves of the cases.
I never noticed the factory marks on the cases.
I thought they were just scuffs or scratches, but when I put them alongside each other it became evident they were intentional marks.
The 2010 on the left has two marks like check marks.
The 2005 on the right has a single mark.
I don't know if this is a mold designation to ID a specific mold position, if it signifies some difference in the case dimensions or just a QC thing, that it was inspected and passed.

Image

I started doing some assembly work.
On the right is the 2010 outer case with what Ural calls "Collar VITON 55x80x10" outer case seal installed.
Left is the 2005 with the same seal and the re-used "Bearing 7000111."

Image

More to come!
Last edited by BinDerSmokDat on Mon Aug 31, 2020 12:36 pm, edited 1 time in total.

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BinDerSmokDat
Hero of the Soviet Union - 2020
Hero of the Soviet Union - 2020
Posts: 3874
Joined: Thu May 06, 2010 2:35 pm
Location: South Jersey NJTP exit 6

Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Mon Aug 31, 2020 12:28 pm

Quick note on the detent assemblies visible above at the 5 o'clock position in their respective cases.
The detent is basically a hollow, flat head set screw, with a spring and ball bearing crimped into the end.
101070506400.jpg
If you are having trouble with the FD slipping unintentionally from 1WD into 2WD, you may want to check that the ball moves freely in the detent and doesn't push in too easily.
If the ball is loose, with no spring pressure behind it, replace the detent.
If the ball seems to be firm in the detent with spring pressure behind it, check for any other issues and if none found, screw the detent in slightly (tighter).

DO NOT adjust the detent to get the bike to go into 2WD easier.
It is suppose to have a certain amount of pressure to hold the engagement fork back in the 1WD position.
If the detent is shot OR you adjust it outward (looser) to make 2WD easier to engage, the fork can slip into "partial 2WD" and trash the teeth on the engagement coupler and/or the splines on the back of the ring gear carrier hub.

So far I've had to neither replace nor adjust either detent.
My detents are screwed in VERY firmly, they won't budge so it may be loctited or otherwise thread sealed.
You may need to break it loose and remove it and reapply loctite when adjusting.
This is one of those "if it ain't broke don't fix it" assemblies, messing with it can only lead to headaches with no upside.
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BinDerSmokDat
Hero of the Soviet Union - 2020
Hero of the Soviet Union - 2020
Posts: 3874
Joined: Thu May 06, 2010 2:35 pm
Location: South Jersey NJTP exit 6

Re: Final Drive Surgery with Pics

Post by BinDerSmokDat » Mon Aug 31, 2020 5:08 pm

I ordered some FD gaskets in May 2019, but being the world class procrastinator I am, I only opened them today.
They were sealed between two pieces of cardboard so I left them like that to keep them flat and unmolested.

What the fnarg? These aren't FD gaskets.

Image

Any clue what they are?

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