Swapping gearboxes: how to? ['81 DIESEL]

[dobryan]

Looks pretty normal to me.
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Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[epowell]

OK, most likely this post will wind up this little adventure with swapping trannies and testing out the 2 used boxes I purchased last year in Poland.

Just to recap, I put in SWAP#1 which was a very dirty box... but it worked very well. Then I put in SWAP#2 which was a very clean and more expensive box - this also works but seems to have some "thunking" issues going into 2nd gear... I decided to put SWAP #1 back in for the long haul since this seems like the best that I have... so after swapping #1 back in and driving it felt like suddenly this box was also experiencing this same kind of "thunking" going into 2nd gear.

So this made me suspect that the "thunking" for both #1 and #2 might have more to do with some other factors.... so I bleed some fluid (NO AIR) out of my SLAVE (and replaced a stripped bleeder)... then did quite a lot of tinkering and tweeking to linkage. I finally got fed up with how the linkage rod runs so high and rubs against the frame that I decided to take a grinder to the rod and shave off at least 3mm from it's height _ then I epoxied on to the under size a section of pipe to make up the lost strength... then painted it white It's amazing - I realize that that rod has been chronically rubbing against the frame, and now that it is finally free there is a whole lot less noise and vibration from the engine... it has made a big difference.

I also swapped on there a totally straight pin which in itself majorly improves shifting. Previously I had a somewhat bent pin and I would adjust the pin so that it would be bending downwards - that way it would lower the rod and thereby enable it to clear the frame >>> but with a straight pin the rod was smack up tight against the frame making it mandatory to take some other corrective action to remedy the rubbing.

You can see from the fotos another defect I have in the linkage... the rear rod section is 5cm too short therefore the male coupler end only goes about 2mm into the female coupler of the front rod section... I solved this by bridging the 2 couplers with a bent piece of sheet metal and a big 'ol clamp stolen from a bicycle seat. It works.

Shifting is now pretty good again with SWAP#2 in there... I think I have it about as good as it can get, and it's time to stop obsessing on this and get on with some other things like TRIP PLANNING!!!

After getting this piggies out > here is a foto of the NEW throw-out bearing... seems that in just a few days it has worn somewhat (see the orange metal exposed) - my guess is that the silver metal is just a thin coating... OR... does this indicate something wrong?

Here are fotos of the new painted and ground down linkage rod.

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[dobryan]

Good job. Now go traveling.


_________________
Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[epowell]

[epowell]

I think I might have discovered the shifting problem into 2nd.

What I noticed, when looking at the balls when shifting, is that to go "over" to 2nd takes a lot of sideways pressure from the rod.

I have a "ghetto fix" for the connection between the front and rear sections of the rod... the rear section is too short so it only slides into the front section about 2mm, and I bridged the space with a piece of sheet metal.

What I think is happening is that because of this weak connection it is not providing enough stability to support the "sideways push" over to 2nd... so therefore the ball is not quite far enough over.

I think the reason why this problem "appeared" late (by SWAP#2) is probably because when I left the linkage rod hanging... on - off - on - off... this LOOSENED that ghetto fix connection too much...

I go now to take some vids of the shifting... and then probably to try to strengthen the middle rods connection.
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[Zeitgeist 13]

Yes, these shifters are very sensitive to any shaft rotation away from a precise optimal position. I found this out when I combined an 091/1 front section with an 091 rear section. It took lots of fiddling before I dialed it in. I finally figured out which way to rotate the shaft after staring up at the forward shift box and seeing what was hanging up during shifts. I then crawled back and rotated the assembly to reduce these hangups.
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Casey--

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

[epowell]

[epowell]

In my quest to solve my rough shifting issue... I have noticed brake fluid - tiny amounts, but increasingly more - collecting up by my feet near the pedals... all year this has been collecting and I finally had a good look there, and see that there seems to be a kind of secondary clutch cylinder down by the pedals - I don't even know what it is, but it is definitely leaking. So obviously this is a real problem and certainly can affect shifting... now I need to learn what this is and likely just go and order a new one - THEN reassess my shifting.

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[epowell]

OK, so I changed the clutch MASTER and SLAVE cylinders and shifting has improved noticeably. It is still not 100% perfect so I will keep tweeking. I have a feeling there is too much sloppiness in the stick shift base... but, all in all, it is now acceptable and the whole issue is slipping lower on my list of priorities.

So, in looking back and deriving accurate conclusions from these 3 swaps I think I can be happy that all 3 of my DMs are working (I also have that 4th one which won't go into 1st). SWAP#2 has a pronounced issue with 2nd thunking, but certainly this had to have had something to do with the failing clutch MC that I had not noticed. Actually that is a pity that I noticed the bad MC too late because in fact SWAP#2 might well have turned out to be much better. The sad thing is that I still don't really know - I do know that that box worked quite well, but it's defects might be simply because of that bad clutch.

Anyway, the end result is that I have SWAP#1 in there permanently now, and I have SWAP#2 and the ORIGINAL sitting in the attic ready to be used again if necessary. So the result, it seems, is that I probably have many years of DMs at my disposal with just these spares that I have now.

But still, looking into the future, I want to have a good plan in place. My next major step is to rebuild my spare JX block and get that installed. I intend to have that done by this time next year.

So my long term plan for my gearboxes is as follows:
1) keep SWAP#1 in there permanently
2) consider SWAP#2 as a permanent backup
3) take my ORIGINAL and my broken-DM and consolidate these 2 boxes into a rebuild. I will use the housing from the broken-DM (which is excellent) and I will sacrifice the housing on the ORIGINAL (because it is bad) to use as a rebuild jig.

....sound like "a plan"?
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[epowell]

I have noticed since the weather started getting colder that the tranny is grinding again more than usual at least until the van really warms up - I guess this is because with the cold weather the tranny is getting a lot more cold, and it seems that when it is cold the synchronizers are not working as well as they should.... when it is cold I need to wait between shifts and then shift SUPER SLOW - if and when I am VERY careful I can actually shift without grinding - but it is really finicky... I guess I have to accept that the synchronizers are all toast - and this tranny really needs a re-build.

But otherwise it is working great.

...well, except for when I reverse a long stretch it makes a pretty ugly low frequency noise. I am not so concerned about this because I rarely reverse long stretches AND other than the noise it functions perfectly.
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[Gizmoman]

Glad to read that you're getting a handle on your tranny issues.
Not to start a gear oil debate but, have you considered running synthetic gear oil? I'm running Swepco 202 in mine and it's smooth even at 17° F.
My synchros are all fairly new though. I do believe oil viscosity plays a huge role.
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82 Vanagon Westy - AAZ 1.9 TD, HE200 Holset, WAIC, 27.75 dia tires, Electric power steering, 5-speed AAP w/.078 5th
Oversize spare carrier - stock location (no longer for sale).

[epowell]

[MarkWard]

How cold is cold?
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[beach_creature]

When the temps drop, shifting is more difficult. I notice this in the winter for sure. Shifting becomes smooth as the gear oil warms up.
I use Swepco 202 as well. I believe there was discussion on the 202 with difficult shifts when cold, especially shifting into 2nd.
I would shift very slow when the oil is still cold. Don’t force things. Hold the clutch in a little longer when shifting while cold. Do this and you shouldn’t have grinding.

I would also always use a high quality synthetic.
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84 Westy
1.9TD AAZ
5spd manual with Locking Peloquin TBD

[epowell]

I put this tranny in in May so I have not yet experience real cold. Right now it is still over 10*C !! ...hardly cold at all, but I can feel it.

Yeah I just need to be very very slow.

But to be honest, with the original tranny I had in there I never noticed any shifting problems at all - even into 2nd. Maybe I should put that one back in??
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[MarkWard]

For the synchronizer ring to get the gear up to speed for a smooth shift, it needs to “grab” it. The gear has a cone shaped face that matches the taper of the synchronizer ring. As the synchronizer wears, it has trouble grabbing the gear. It needs to grab the gear through a film of lube. When the transmission is cold, the lube is thicker and gets in the way of the “grab”. It’s not a serious problem, but does indicate normal wear. A thinner lube in cold climates helps the grab take place. Once the oil is up to temp, it thins and shifts improve. It’s not uncommon to use a lube with less viscosity in cold weather. Slower shifts and even double clutching as suggested will get you many more miles.

Disclaimer. This is an over simplified explanation. You Tube surely has some good videos of how a brass Syncro works.
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[Gizmoman]

[epowell]

Summary of my tranny test:
#1 - was the original box that I had in there for 3 years before doing anything - I drove this box in all seasons and I never ever noticed any hint of hard shifting into 2nd (going up or down) even in cold weather. There was a tiny bit of roughness sometimes going up to 3rd if I was not slow and careful. The PO made a big big point of telling me that this is a "great box" - even tho the case is badly corroded.

#2 - I bought this one cheaply in Poland and swapped it in May 2019 (6 months ago) and it worked fine but has always been a bit "brittle" going into 2nd - especial when cold (however it is almost always smooth shifting DOWN to 2nd). It has exactly the same kind of 'sensitivity' going up to 3rd, like box #1 [but I won't complain about this because it is minor and solvable with slow shifting.

#3 - I also bought this in Poland and it was a bit more expensive and very clean and nice... I had very high hopes for this box but after putting it in realized that the cruchiness of 2nd gear was really TOO MUCH. So I put #2 back in there - but was still concerned about 2nd gear even tho #2 was better than #3.... however right at that time I came out of my DENIAL regarding my clutch master cylinder - I had been ignoring the little puddle of brake fluid under the clutch pedal for about a year (!) I didn't even know there was another cylinder under there (!), so I replaced that and also the ball under my stick shift, and did extensive tweeking on the shift linkage in all areas... this DID IMPROVE shifting into 2nd but it did not totally eliminate the problem.
>>> so the pity is that when swapping in #3 there were several other problems I had not yet resolved therefore I can't say with total certainty that it is worse than #2.

I wonder why the PO insisted that #1 is "great" and in fact it did not have any problems with 2nd gear? Maybe this box was recently rebuilt? ...or maybe the oil was so old that all the grit in it was helping to grab? --- however I do remember, with #1, checking the gear oil level and noticed that the oil was super clear and clean - looked brand new (at least that was at the TOP of the box... maybe all the dirt and crap was at the bottom?)

Anyway, I am told that it is even possible to shift WITHOUT a clutch! ...and when I drive this thing cold, it really almost feels like I am having to do that. It takes a very sensitive and slow hand, when cold, to get from 1st to 2nd without grinding. I CAN do it. But it takes an inordinate amount of skill and concentration. In fact, every single shift I make I do with the same care you would have to take installing purflings around a violin's edge.
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