diagram for tubes on difflocks

[wimwolf]

Hi,

can anyone help me out with an electric diagram from the shift-valves - lights- for the diff.lockers on my syncro?
I have the Bentley manual but the info about this is pour.
I already found a diagram for the tubes but it is only to see how it works (understood).

Is there someone who has a nice drawing of how the airtubes must be, both front and rear locks.
I think my tubes are badly connected.
Would be great. Thank you.

I found a small printplate(?) wich was protected with a foam cover? What's this again?

[jebiga41]

look on the syncronauts website all there

[toomanytoys]

Do you suspect the dash has been apart and not put back together correctly? normally the problems come from the other ends..

WHats happening/not happening to make you think the control panel is at fault?

[jed the spread]

I found a small printplate(?) wich was protected with a foam cover? What's this again?

It makes your light on front diff lock flash.

jed

[wimwolf]

ok, i'll start with the syncronauts website and start from the beginning.
I always thought the valves worked with air pressure instead of vacuum

Knowing this i checked the vacuum reservoir (tripple bal underneath the bus) and the small non-return valve seems to be stuck, so it starts from the beginning. Even after removing the valve, the big tube (collector towards brake)
didn't seem to suck air? I suppose this must be the case?

So a lot to be learned over here.

grts from Belgium

[Aidan]

Petrol or diesel ?
Engine must be running to generate vacuum, which is used by the brake servo and a little bit for the vacuum system for the difflocks.
One way valve is still available from VW , they often fail, but can be revived sometimes with wd40

if you have no vacuum on the main line then your brakes will be hard to apply
The diesel has a pump, the petrol uses manifold vaccum and there's a one way valve in the engine bay, big yellow/black one

[wimwolf]

I see…
Engine is a petrol 1.9 DG, I tried to clean the small one way valve near the reservoir and used WD40.
If I blow on it, air won’t pass. Air do passes trough (one way) if I use the compressor. (then it goes “klick”) Broken?
The valve in the engine bay is found and tested. If I remove the tube from the manifold the engine stops. (normal I assume?)

So I first check if there is a vacuum in the main line + the small tube going to the difflock reservoir?

Brakes are quite hard indeed, but no problems with braking (I think) but I only did small testdrives.

@Jed, is it only the frontdiff that flashes?

Grts. Wim

[Aidan]

yes only the front flashes when you pull the knob out before it actually comes on when the light comes on and stays on, rear is only off or on, the flashy thing doesn't matter really it's just an idiot warning, ie" did you really mean to select front diff lock ?", but once they are working well then the come on so quick you barely notice the flashing and because of the manual interlock that means you have to rotate the switch before pulling it on you are unlikely to pull front instead of rear
however not all vans have the mechanical interlock , I've seen factory set up without and also modified set up without

[wimwolf]

Fixed,

tubes were ok, I only replaced the non return valve.
Rear diff light goes on when I activate the knob.
Fornt diff is not connected for the moment so this one is on HOLD for the moment

thanks for the advice.