I'm having trouble...

Syncro 4&4 Discussion and Q&A last answered over 2 years ago.
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Aidan
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Re: I'm having trouble...

Post by Aidan »

when you fitted the new spigot bearing did you ensure that is is recessed 1.6mm from flush with the end of the flywheel ?
If the spigot bearing is not fitted deeply enough then the outer cage of the bearing can run against the sloped shoulder of the input shaft and the needles run out of parallel and catch meaning that the engine will still be turning the input shaft even though the clutch is fully disengaged
late diesel input shafts have parallel spigot surface with a recessed stress relief and so are not as critcal as with early versions - it would seem that this possible issue became apparant to VW over the years and they fixed it - all the aftermarket input shafts have the late type spigot end.

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Essex Nige
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Re: I'm having trouble...

Post by Essex Nige »

Aidan wrote:when you fitted the new spigot bearing did you ensure that is is recessed 1.6mm from flush with the end of the flywheel ?
If the spigot bearing is not fitted deeply enough then the outer cage of the bearing can run against the sloped shoulder of the input shaft and the needles run out of parallel and catch meaning that the engine will still be turning the input shaft even though the clutch is fully disengaged
late diesel input shafts have parallel spigot surface with a recessed stress relief and so are not as critcal as with early versions - it would seem that this possible issue became apparant to VW over the years and they fixed it - all the aftermarket input shafts have the late type spigot end.

the spigot bearing is flush with the flywheel, so this might be the issue then
1988 syncro 1.9 AAZ, 1984 Doka 1.9 1Y, 1980 Aircooled camper 1.6CT (resting)

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Syncrobaz
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Re: I'm having trouble...

Post by Syncrobaz »

Re prop, thanks for your info Aiden I guess old habits die hard!! I will carry on though 'cos I love the smell of tipex in the morning I gather you are having a sabbatical, will you still be contactible to share your knowledge with us lesser mortals? Regards Baz.
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Aidan
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Re: I'm having trouble...

Post by Aidan »

oh yes I'll still be around jut not 24/7

and I know you've probably forgotten more than I'll ever know more

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syncroandy
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Re: I'm having trouble...

Post by syncroandy »

Sorry to troll, but FWIW I think there are two part nos for that bearing, possibly there's some combination of bearing and crankshaft that results in this problem.

A

Aidan wrote:when you fitted the new spigot bearing did you ensure that is is recessed 1.6mm from flush with the end of the flywheel ?
If the spigot bearing is not fitted deeply enough then the outer cage of the bearing can run against the sloped shoulder of the input shaft and the needles run out of parallel and catch meaning that the engine will still be turning the input shaft even though the clutch is fully disengaged
late diesel input shafts have parallel spigot surface with a recessed stress relief and so are not as critcal as with early versions - it would seem that this possible issue became apparant to VW over the years and they fixed it - all the aftermarket input shafts have the late type spigot end.
Syncrosport (taking a break as of summer 2024)
Volkswagen Transporter, reloaded.

252 GC5 EJ25 AAN L90D

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Essex Nige
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Re: I'm having trouble...

Post by Essex Nige »

I would just like to say thanks for the help you fellas have given me in this thread, The SYNCRO is now mobile, after dropping the box again and tweaking i got the fella next door to dip the clutch so i could see what it was doing.... Bugga all is what it was doing so after a quick bleed i'm sorted... Its strange how it needed bleeding tho even tho i never touched the slave, anyhow its sorted...


A big THANK YOU
1988 syncro 1.9 AAZ, 1984 Doka 1.9 1Y, 1980 Aircooled camper 1.6CT (resting)

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"We are each of us angels with only one wing, and we can only fly by embracing one another..."- Luciano de Crescenzo

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syncropaddy
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Re: I'm having trouble...

Post by syncropaddy »

Go off and get it dirty ....
syncropaddy


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toomanytoys
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Re: I'm having trouble...

Post by toomanytoys »

Clutch
Really important to make sure the clutch fork ends are nicely rounded and NOT flatted.. dress them down with a file and if really bad, build them up with a little weld and dress back..

Prop...
My prop has been on and off more times than I can remember (prob 8-10 times a year) over the last 6 years of ownership (tight VC, not fitted the lovely decoupler) and never had a vibe problem until an enthusiastic crest (read as flew up, front wheels in the air and crashed down on prop bars and prop) of a steep climb and bent it....

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syncropaddy
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Re: I'm having trouble...

Post by syncropaddy »

syncropaddy wrote:Makes no difference whatsoever as the prop is balanced off the vehicle. It would make a difference if the prop was balanced on the vehicle but it isnt!


Syncrobaz wrote:Marking prop standard practice in this country!! Been doing it for over 40 years!!

Toomanytoys, you must be Irish ... I know Aidan is cuz you two do the prop thing the way we do it over here! Either that or you fly against convention!
syncropaddy


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Aidan
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Re: I'm having trouble...

Post by Aidan »

syncropaddy wrote: you must be Irish ... I know Aidan is cuz

born at Croke Park as the saying is

Syncrobaz
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Re: I'm having trouble...

Post by Syncrobaz »

Can we move on from the prop thing? Its getting a bit anal now!!!
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94 RHD jx doka 16"

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