Internet Armchair Diagnosis: transmission

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Eric Wills
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Re: Internet Armchair Diagnosis: transmission

#16 Post by Eric Wills »

No guarantees on old parts that have been through a major failure, even if Magnafluxed. Had another customer that had the same initial problem of snapped off diff housing cover. Mag did clearly show a crack on one of the pinion teeth.

David--this was the trans I shipped back and you did final assembly? This is the first I have heard of your ring gear failure.

EW
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David Jones
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Re: Internet Armchair Diagnosis: transmission

#17 Post by David Jones »

Eric, I did not call you because it was not something I could attribute to your repair. I happened to be talking to Vic and at that time he was able to slip me in and I was able to take it up to him and get it repaired quickly. When you did it I had the luxury of time as the car was still being reconstructed. I had no complaints about your work.
If you remember all I did was put the axles in and the planet gears. Those I did not ship to you.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
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Thom Fitzpatrick
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Re: Internet Armchair Diagnosis: transmission

#18 Post by Thom Fitzpatrick »

Installed the new wheel bearing, spacers, and seal on one side today. I thought I'd share a trick I have to getting the backing plate and bearing cover lined up and installed more easily: I thread a couple of studs into the axle tube and bolt down the backing plate using the other two holes. Then I gently remove the bolts, and slide the cover on.
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2018-08-18 15.32.55.jpg
1956 VW Single Cab
1957 Porsche 356A Sunroof Coupé
1957 VW 23-window Deluxe
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Thom Fitzpatrick
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Re: Internet Armchair Diagnosis: transmission

#19 Post by Thom Fitzpatrick »

When I originally took the drum off (a year or so ago, when I did the brakes) there was this spacer in this position as you see here. I'd never seen one like this and I left it out when I re-assembled everything. I didn't see this in the manuals - is this meant to tighten up the drum or am I missing something?
2018-08-18 16.51.15.jpg
1956 VW Single Cab
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Vic Skirmants
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Re: Internet Armchair Diagnosis: transmission

#20 Post by Vic Skirmants »

It's not original to that location. Probably installed to add some clearance.

Thom Fitzpatrick
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Re: Internet Armchair Diagnosis: transmission

#21 Post by Thom Fitzpatrick »

Ok, over the past week or so, I installed new wheel bearings (the old ones looked great, though) new seals, tightened up the axle boots, put in new gear oil (generic GL4 - didn't want to waste $100 worth of Swepco) and changed the oil. While I had it in the shop and the A/C was going, I installed some headlight guards I had laying around.

Today I took it for a little test drive.

Nope - the sound is still there. It's a sort of "kla-klunk" and is loudest when making right turns. I tried to take a video to capture the noise; I'll see if I can edit something useful out of it.

So, any recommendations for a shop in the Sacramento area to rebuild a transmission for me?
2018-08-26 12.14.55.jpg
1956 VW Single Cab
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Geoff Fleming
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Re: Internet Armchair Diagnosis: transmission

#22 Post by Geoff Fleming »

It is very easy, when working with the axles, to pull one out a bit too far, allowing one or both trunion blocks to become dislodged at the inner axle end. This will result in klunking on turns.
The trunion blocks are flat on the side that lays against the flattened ends of the axle and a half-round on the outer side. Not too hard to correct but annoying, requiring opening the side plates of the trans. and gently easing the blocks into place. Care must be taken not to pull the axles outward when re-assembling everything.

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Re: Internet Armchair Diagnosis: transmission

#23 Post by Thom Fitzpatrick »

Geoff Fleming wrote:It is very easy, when working with the axles, to pull one out a bit too far, allowing one or both trunion blocks to become dislodged at the inner axle end. This will result in klunking on turns.
The trunion blocks are flat on the side that lays against the flattened ends of the axle and a half-round on the outer side. Not too hard to correct but annoying, requiring opening the side plates of the trans. and gently easing the blocks into place. Care must be taken not to pull the axles outward when re-assembling everything.
trunion blocks

Aka fulcrum plates?

I've dislodged one before, while assembling a bus transmission, but the symptom in that case was the axle would not spin at all.

Is there not a big circlip holding down a spacer, like there is in VW Type I/II/III transmissions?
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Vic Skirmants
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Re: Internet Armchair Diagnosis: transmission

#24 Post by Vic Skirmants »

Thom; no circlip in a 356 or early VW split case trans.

Thom Fitzpatrick
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Re: Internet Armchair Diagnosis: transmission

#25 Post by Thom Fitzpatrick »

Here's the sound clip of the transmission noise: https://www.youtube.com/watch?v=v3kKKWWa5ZI
1956 VW Single Cab
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Thom Fitzpatrick
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Re: Internet Armchair Diagnosis: transmission

#26 Post by Thom Fitzpatrick »

So, before I go and rip my axle tubes off - what are the chances that the issue really is the axle falling out of the fulcrum plates? Everything was hunky-dory until it just started making the whining and clunking out of nowhere.
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Re: Internet Armchair Diagnosis: transmission

#27 Post by Vic Skirmants »

If everything was fine, and then the noise started, then it is not a fulcrum plate issue. If a fulcrum plate was dislodged, then the axle tube hex flange would get distorted when tightening the nuts.

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Re: Internet Armchair Diagnosis: transmission

#28 Post by Thom Fitzpatrick »

Is there anything worse than when someone starts a thread and then never follows up?

It turned out that my differential housing was broken.
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1956 VW Single Cab
1957 Porsche 356A Sunroof Coupé
1957 VW 23-window Deluxe
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Ron LaDow
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Re: Internet Armchair Diagnosis: transmission

#29 Post by Ron LaDow »

Thom Fitzpatrick wrote: Fri Apr 26, 2019 9:30 pm Is there anything worse than when someone starts a thread and then never follows up?
It turned out that my differential housing was broken.
There must be, but the guys who come back later and let us know get special dispensation.
Those fulcrum plates have been mod'ed for additional lube; you?
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Thom Fitzpatrick
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Re: Internet Armchair Diagnosis: transmission

#30 Post by Thom Fitzpatrick »

Ron LaDow wrote: Fri Apr 26, 2019 9:38 pm Those fulcrum plates have been mod'ed for additional lube; you?
Not me; as far as I know those are 356 fulcrum plates. I'm tempted to use this style in my next VW transaxle install
1956 VW Single Cab
1957 Porsche 356A Sunroof Coupé
1957 VW 23-window Deluxe
1957 Mercedes Unimog 411
1963 Mercedes Unimog 404
1965 Jaguar E-Type
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