091/1 rebuild project

[Zeitgeist 13]

Like Mark stated, there's significant parts crossover between the 094 and 091/1, but technically speaking an '87 factory four speed trans would be an 091/1 using VAG nomenclature. Using that same nomenclature an 094 would be a factory five speed/Syncro. An 091 is a completely different beast altogether. Look in your Bentley, which clearly shows three separate transmissions in the T3 range; 091, 091/1 and 094.

Weddle and perhaps other builders/suppliers have obviously chosen to see the nomenclature break as the distinct point in '83 when the WBX engines/five speed diesels were introduced, and thus have opted to just call everything from that point an 094. That's fine for lots of the internal items, but it can get a little confusing when referencing other variations on the theme.
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Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[?Waldo?]

[DanHoug]

Tool Tip #2: lock ring tool - i was having a bugger of a time getting the 3 lock rings off under the gear carrier cover. made this tool out of a Swix ski wax scraper and it works perfectly to pop the lock rings off, especially the 3 lobed one. the notch was made from the bench grinder wheel.

trying to drive the pinon shaft back now and it seems VERY solid. used a thick brass drift and a 3lb hammer and didn't beat too hard but it also didn't move. need to mull a bit and try it again. shift shaft removed, gear carrier screws out, reverse gears removed. am i misisng something?

-dan

[DanHoug]

more progress... got the pinion bearing out of the housing by tapping it out from the race using a sleeve from a front hub installation kit.

then pressed the mainshaft out of the gear carrier by suspending the gear carrier on 2 - 12" 4x4 posts. worked just fine and was completely stable. had to apply more ram pressure than i expected so i heated the inner bearing race a bit with a propane torch and put a small bolt in the dimple in the end of the mainshaft. then it pushed out fine. despite my best attempt and padding and being ready to catch the gear cluster, i dumped it on the floor! no pictures

beginning disassembly of the mainshaft, i come the to 3-4 slider hub which was the whole goal of this pre-emptive rebuild on a perfectly functioning but high mile transaxle. it was cracked and i felt vindicated for taking apart a perfectly good unit.

all the synco teeth look good with sharp edges and no wear patterns. you still replace all those regardless while in the tranny?

and another question... GoWesty talks about always replacing 4th gear to reduce warranty comebacks on 4th popping out of gear. here's mine, what are the three slight cuts across the top of each gear tooth??

[gears]

Looks like your timing was excellent, Dan. That hub was just about to come unglued.

I believe the three marks quickly indicate the 4th gear ratio. While your idler looks in pretty good shape, the drive flanks show a lot of miles. Sleep easy by changing it along with slider & hub. Synchronizer gaps can be measured, but it's usually smart to just change those out, too.
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aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

[DanHoug]

so i was delayed in my rebuild... a combination of intimidation, parts ordering, and busy with other things. firing it back up. last couple days i assembled the pinion and mainshaft strings, using new synchros, 3-4 slider hub, and circlips. here's a shot of the Weddle thrust plate i installed. it seems to be the bargain part in the 091 world as it is around $100 for the plate and machined cover.

the bearing had pounded the old thrust plate a little and the old cover was a little hammered, probably should have sleeved the mainshaft gear carrier but i've used Loctite 609, this Weddle thrust plate, and the machined cover. i think it will be fine. the new bearing still had to be pressed into the gear carrier.

[DanHoug]

the pinion bearing intimidated me for a spell... popped it off with the press but broke the inner race carrier as i mistakenly applied pressure on the threaded section. here's a tool i made to get the inner race off. a 2" thrust washer, cut in 1/2, suspended on a 2" plumbing coupler (grubbed out the threads for pinion clearance), and held together with a hose clamp. worked wonderfully.

[DanHoug]

well, the transaxle is done! lots of space between my last photo/post and the conclusion. it was intimidating, fun, expensive, slow, and hopefully successful!

it shifts nice on the bench with a clean neutral but we'll see how it actually runs once i do an engine refurb. bought all the parts thru Weddle, used the Rick Long CD of advice on the 091 (mostly the info transferred, and it was well worth the cost), bought a few tools but not that many, borrowed a couple, and overall was worth doing.... IF the thing works!

the cases were extremely corroded as this is a MN van. but i painted them with aluminum primer then topcoated with Rustoleum oil based enamel. Thermally it would be best to paint the transaxle black, but the dominant mode of cooling is conduction to externally propelled air, and the radiative proportion is insignificant. so gray it is because i like the color.

-dan

[DanHoug]

transaxle in and been driving it. all seems good, shifts nicely and is quiet. drained the el cheapo gear oil at 250 miles, plug is this:

wasn't too bad, some bronze colored swirlies in the oil pan. refilled with Swepco 202, tho i sorta felt like i should wait for one more oil change. too impatient. shifting after the Swepco was somewhat better, not "Holy Cow!" better.

interestingly, the Swepco 202 was the same color-- a blue-green with dark moly undertones, as the expensive Schaeffer oil in use in my BMW airhead trans. in THAT application, the Schaffer is proven to drop transmission temps and at least one BMW transmission rebuilder won't let his rebuilds run on anything but. i'd love to know if the Schaeffer and Swepco are the same stuff.

-dan

[Vanagon Nut]

Thanks for those images, information and report back Dan; that's impressive that the JB held up for tool use (albeit only this job but maybe it would do more?). I used JB to bolster up some areas on my '88 transaxle case including the threads for the 11 mm head bolt for the clutch cross shaft bushing set; about 1/2 of the threads were gone. Though the areas were not high stress per se, I really thought the JB would at least crack a little. Haven't closely inspected but so far, the JB has held. (in some cases a washer was used in conjunction with the JB)

Nice to see that a DIY type can do this job. I have the Long Enterprises DVD and frankly it all seems overwhelming but who knows; maybe someday I'll tackle a transaxle rebuild.

Neil.
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1981 Westy DIY 15º ABA

1988 West DIY 50º ABA

VE7TBN

[DanHoug]

many of us here have done our own 091/1 and while it intimidated the heck out of me, it really proceeded in a fairly linear manner. at a minimum, you absolutely need a hydraulic press, the pinion bearing socket, the 1st gear collar holder + splined socket (or an old gear that fits on the end of the pinion shaft), and a Visa card.

i'm happy i did my own, but it also made me appreciate the value of a good rebuilder. i think their fees are reasonable after doing one!

it's funny how my mind pictures the assembly now while driving down the road. that's part of the return for me in doing stuff that has marginal payback over paying someone that can do it way quicker.

-dan

[DanHoug]

just an update... i'd had somewhat balky shifting into the gates and could feel the shift lever seemed slightly too far to the passenger side. had adjusted the shifter coupler right after the rebuild but yesterday i did it again to fine tune the position. holy cow, what a difference one spline makes. 2 or 3 finger shifting now, incredibly easy to get into all gears. makes me feel better about the rebuild.

-dan

[Vanagon Nut]

[Zeitgeist 13]

I had a similar experience with the shift gates on my hybrid 091/1 (front section) and 091 (rear section) shift rod. I was having real difficulties with getting it into third and fourth, and seriously thought I would need to radically alter my rear shift rod section to fix the issue. I crawled under the shift box and stared at it for a while, and attempted to move the shifter into third and fourth. Seeing where the interference was, I visualized what needed to be adjusted back at the splines. I rotated the rear section two splines and everything cleared right up. Really nice crisp and clean gates with no notchiness or grinding. Proper adjustment is the key.
_________________
Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[DanHoug]

[Vanagon Nut]

[DanHoug]

one more data point after the linkage adjustment.... my 4th gear rattle transmitted thru the shift knob went away!!!

ever since the rebuild, i've had the common high frequency rattle heard thru the shift knob. it'd quiet down with my hand on the knob or moving the lever around but it bugged me, thinking i may have overlooked a failing bearing. well, that noise is now gone. i hear it in 3rd gear but as soon as i shift into 4th it is quiet and stays quiet on a drive of 60+ miles. this was a very happy discovery!

-dan

[DanHoug]

ok, i did it. in a moment of indulgence, i ordered ANOTHER gallon of Swepco 202. i'm going to drain the current fill of 202, save it in a jug to settle out over the next year, and put in a fill of fresh 202. this'll keep me going with clean oil for the fore seeable future for annual oil exchanges.

i do like the 202... super nice shifting, no cold weather issues, no gear grinding.

-dan

[DanHoug]

did a 2500 mile gear oil change today with another gallon of Swepco 202. i'll let the previous gallon settle out over the next year and put that back in for annual changes. plug looked great, there was some slight bronze irridescence to the oil but it didn't bother me, as i have all new bronze syncros and they have to scrub in.

here's what i used for a gear oil filler. TOTALLY worth the $9 as i didn't spill a drop. i suffered thru one of those tiny gear oil hand pumps last time and never again.

-dan

[jberger]