[Bosco15]

Completely new to Grand Viatara and 4wd in general.
Please excuse my ignorance. I am trying to source a workshop manual.
The hose that goes into the bottom of the front diff runs to the front of the car. On my particular example the hose has been looped back on itself, bypassing the thing behind the bumper (I think)




Whilst I had the diff on the kitchen bench, I wrapped my lips around hose and blew. It seemed to activate something.
Is this an air locker?
Is the module behind the bumper a pump?
Any reason it has been bypassed?
How do I test front wheels are driving?

Thank you.

[alien]

vacuum hose for the front hubs?

[atari4x4]

you currently don't have 4wd unless someone's fitted vitara diffs, read this thread on how the front diff works on a SQ & how to fix it if it's the pump. viewtopic.php?f=17&t=19613

[Bosco15]

Thank you, Atari, for the link.
Very helpful.
It turned out that I had a combination of problems.
Once I hooked up the pump to the system again, I had a flashing 4wd light. This turned out to be a leak at the hose that links the pipe to the diff, and the last issue that I solved.
The pump pressure switch was turning off the pump at 5psi, when I had removed it and set up a guage to bench test it with. Same problem as discussed in the link.
The pressure switch is a very simple setup once you manage to take the assembly apart far enough to get to it. It is just a small diaphragm in a cylinder. As pressure builds the diaphragm expands and the rod that it's attached to pushes on a micro switch, when it overcomes the resistance of the return spring.
I stretched out the return spring to give a little more resistance and ended up getting 8 psi before the switch is activated.
The output signal on the pink wire was 10.2v and I wasn't getting a 4wd light. I spent a few hours scratching my head, thinking that the control unit would need 12v as a signal, before I found the leak at the diff.
Once I fixed the leak, with fishtank air hose, the system pressurised in two seconds and the 10.2v turned out to be enough of a signal to give me a light on the dash.

[henno]

I love a happy ending.

Especially a cheap one.

[Scrawny]

henno wrote:

I love a happy ending.

Especially a cheap one.

Don't we all!!

[sezed]

Just keep an eye on your fish tank air hose, if you are out wheeling and notice you lose traction and the 4wd light go off, you may have an issue, I predict the fish tank hose will eventually (1-2 years) work harden and fail. Any easy fix, but frustrating. I have had a lot of annoyance over the years with that air hose!

[henno]

Chuck a piece of hose in your toolbox/glovebox/whatever. Problem solved.