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U1300L - help identifying switches

1406 Views 11 Replies 3 Participants Last post by  TRUKTOR
I got switches where the gear levers are and I can't figure out what they are for....

(1) - I can pull out to about 3 inches, but it doesn't seem to make any difference
(2) - is a momentary dial, if I turn it 90degrees I can hear air releasing

Do you know what they are?


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No.1 looks like the Start Pilot pump.
It is missing the knob.
You can pump it up and down like a bicycle pump, to give a shot or two of ether into the intake circuit for cold weather starting.
No. 2, I believe, is the Diff lock-
Should be 3 positions -
2 Drive
4 Wheel Drive
4 Wheel Drive, Diffs locked

I have a civilian truck, so my switch is on the dash, but I ‘Think’ that Military Unimogs had them on the shift plate for a while.

If you don’t know which position is which, when in 4WD Locked, your turning radius will increase substantially.
I’m not so sure about No 2.
While that is a position where the Diff Lock switch was placed on Civilian and Military trucks, the shape of the knob was usually different - either a lever, like the dash version, or a daisy shaped knob with a pointer molded into it.

Sometimes a PTO switch had the shape shown, and a U1300L with a winch would have something like that.
However, peering at the sticker by your switch, I think I can make out
“Emergency Release”.

I don’t know the military trucks very well, and.... I’m rusty.
Since it is momentary, and a 90 degree action, you hear a hiss, and I Think it says Emergency Release, I think it is a
(Secondary) brake release, maybe.

Definitely not a Diff Lock switch.
Ah....good, but the “Emergency Release” would not seem to relate to powering up a sweeper.

As far as the start pilot, you won’t have to crawl under the truck.

If the system is intact, there will be a fill port on the front end of the engine, usually on the right hand side (LHD vehicle, at least).

It has a triangular shaped plastic cap, that is spring loaded.

You open the cap and charge the system with an aerosol can, specific to Mercedes Benz, more or less.

Less expensive cans of ether have been tried with varying degrees of success.
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After reviewing the photos, I’d like to correct my previous statement regarding the “Triangular “ cap.

The cap is actually circular, and the plan view of the receptacle is roughly triangular .

It looks like an egg hanging off the side of the engine - the reservoir below the fill port being translucent white plastic.
I don’t have that one, but the part number for the Cold Start knob I have is :

A 000 555 04 40
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