Club 80-90 Forums

Before I start I checked on the syncro naughts website and followed the diff fault diagnosis but nothing described my fault.

Basically I'm not getting a vacuum to the air actuator (3 baseball sized tank).

I disconnected the pipe off the inlet manifold which cut the vehicle out so no air leaks. I have blown and sucked through the one way valve (cheers Jed) and that works.

The only thing I think it could be is a mix match of pipework from the air tank which may have a small hole?

I pulled the air line off the air tank and there is no vacuum there but it only branches off air pipework from the one way valve.

I am getting nothing either from the diff lock knobs in the cab or at the diff lock actuators.

My servo functions as it should so there shouldn't be a fault along that line?

I'm stumped any ideas?
Cheers all

There is no none return valve near the tank under the van, Cant be right can it? I wasnt sure as its a 1.9 petrol on a carb so not 100% familiar its this set up.

jed

probally a blocked t piece in the servo line phill

But surely the servo wouldn't recieve air as the diff locks are before the servo? That's what's got me wondering?

It has been butchered before by the look of it. But never having seen this system before I'm not to certain.

ok main vac pipe runs to the servo from inlet manifold / pump. there is a little t off close to the vac reservoir. that is the start of the vac system for the doff locks. i`ve seen that t block so no vac is allowed in to the diff lock system. there`ll be vac in the brake system as the pipe is a larger dia. use a little pic or drill bit and make sure the t piece is clear.

once thats clear its just a case of progressing through the system slowly making sure all leaks are banished.

Anyone got a working link to the Troubleshooting the Diff-Lock Actuator Vacuum System (detailed) – Dr Rainer Woitok?

Its not working for me, thuis link takes me to an expired page..

http://www.club80-90syncro.co.uk/Syncro ... System.pdf" onclick="window.open(this.href);return false;

E D I T, this link works, the top link in the help page is dead..

http://www.club80-90syncro.co.uk/Syncro ... System.pdf" onclick="window.open(this.href);return false;

Right I've picked up a new one way valve and a new vacuum tank. I'm still not getting a vacuum anywhere.
I've cleaned out all pipe work now I'm at a loss.

I'm getting good suction from the inlet manifold to the servo but along the main feed pipe there's a small t-piece that takes the line off to the one-way valve nothing?

Am I missing something?

I just want them working now I even dreamt about them last night.

Well you did wan,t a syncro !!!

I was up at 7 outside looking at it, downloading faults, diagrams and it's still a no show

Got any vacuum pipe and connectors you can use to short circuit bits of the existing set up to soundness check it?

You have vacuum at the manifold but its not getting to the reservoir?

Run a temporary pipe from your manifold to the new reservoir via the new one way valve and then cobble that up to the feed to the diff-lock knobs on the dash. If you now have vacuum at the reservoir you can concentrate on the pipe that runs from the engine bay to the reservoir, it may be crushed or split or blocked.

If you still have no vacuum at the reservoir check you have the one way valve the right way round and if thats all good start double checking the vacuum source.

Mudlark wrote:
You have vacuum at the manifold but its not getting to the reservoir?
.

Yes but it's getting to the servo? So in theory it should just be the blocked T-piece? I've been on it all day now so I've just ordered a new servo pipe,vacuum pipes and T-pieces I just hope that cures it otherwise it will be a non diff locked syncro

2wd is so much easier lol

Have you tried running a small drill bit in to the t piece. It's probably blocked with gunge.

One-way valve around the wrong way if its been messed about with... ?

And as lee... says, doesn't take much to block those small pipes and connectors, yet they're quite sufficient to transmit sufficient vacuum to the actuators via the switche valves.

However, everything has to be right for the actuators (throttle units) to work... aligned exactly with push rods (not overtightened to brackets either, which distorts them). etc etc. Then they work pretty reliably and consistently

The grommet that seals the pipe as it enters the three ball reservoir had gone on mine, showed good vacuum but would not hold it or create enough stored vacuum to operate the diff-locks. My favorite way is to use the spare actuator that everyone should have in the garage to hook up to your vacuum lines and see what kind of a pull you get. They are quite powerful, and this test will only take a few minutes to do, and will show if it is the internals of the diff-lock that are seized, or a problem with the pipework.

I also had a diff-lock knob pull (for want of a better name) fail, it was an aftermarket one though, but it kept me guessing for 6 months as vacuum was shown on the system, but not enough to pull the de-coupler. I figured it out by switching the rear diff-lock pipes to the de-coupler and it engaged straight away.

Simon.

phill you say your not getting vacumn to the vacumn reservoir. there is only a short pipe, 1 way valve and that t piece situated in the main servo pipe before the reservoir.