Syncro vacuum diagram for front/rear diff-lock controls?

[syncrodoka]

[syncrodoka]

Exploded view

The vertical fork on the right is attached to the other side of the pin that will not allow it to twist.

[davevickery]

I now have my locker installed (on my 2wd van) and I tapped into the brake booster line upfront under the removable panel. My question is, did the stock setup tap into the same line, and was there a pressure reducer somewhere in the system? I can't find anything in the Bentley. Mine works fine, but it seems like there is a lot of vacuum on that line and I am wondering if that is the same amount of vacuum the stock system would normally see. I am not using the cannister, just tapping straight into the brake booster under the dash. It hisses when I switch on/off and locks/unlocks very quickly compared to my previous syncro which always worked well. I just want to make sure I am not putting too much pressure to the system as it is constantly under vacuum and judging by my previous stock syncro it doesn't seem to need much vacuum to activate the locker .

If anyone knows I would appreciate a reply or if it is covered in the Bentley and you know where, I can look it up. Thanks very much,
Dave

[tencentlife]

Dave, even if a restrictor were inline, it would't reduce the peak head of vacuum available in the system at rest, which when applied will quickly equalise to the same head once the air is displaced due to servo movement. More simply, it's all under the same negative head most of the time, and that is equal to peak manifold vacuum.

It only takes ~1 lb. of pressure to work a locker rod, but the servos can exert ~30 lb. of direct pressure.

I also tapped into the brake booster line and use the booster as the reservoir. Doesn't alter brake efficacy nor locker operation.
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[AIR_COOLED_EXPRESS]

[syncrodoka]

That connector is for the flashing unit for the front lockers. If you don't have front lockers and the flashing unit it is a non-issue.

[AIR_COOLED_EXPRESS]

[CaptTurbo]

I'm pleased to run across this thread. I've recently revived my '87 Syncro after a number of years because of vexing grounding issues caused her to be parked. My rear locker is not working and I suppose it isn't too surprising since they should be actuated once in a while to keep their function.

[dkonzy]

I just installed a decoupler and found the engage/disengage sensor connector on the decoupler itself...where do I plug the other end into on my dash so that the middle green indicator light will work and I finally can say i've got 2/3rds of the green lights I want on my dash?
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1987 Syncro

[syncrodoka]

Put a bulb into the middle position of the locker panel. The wiring is already there from the decoupler to the locker panel from the factory on locker equipped vans.

[dkonzy]

Awesome thanks! Bulbs already in there...

Having trouble locating the existing brown wires and plug...where does it split off? I want to be able to trace it from somewhere....
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1987 Syncro

[syncrodoka]

Having trouble understanding your question.
The wiring from the decoupler and lockers are all wired into the white plug that plugs into the simple circuit board behind the locker panel. The brown wire is just ground. Your van is a factory rear locker equipped van?
The picture above shows the plug just above the person's thumb.

[zeohsix]