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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Mex-Busnut on November 07, 2011, 12:10:14 PM

Title: Need help identifying these sending units.
Post by: Mex-Busnut on November 07, 2011, 12:10:14 PM
Dear Friends,

Our vehicle electrical system was a big mess. In the bunch of cables running from the cockpit back to the engine compartment (under the center aisle floor), we had wires melted together, cables made up of as many as 4 splices, live wires with bare ends sparking off the chassis, and cable runs connected to nothing at either end. No wonder my batteries kept going dead!

We also had several non-functioning gauges on both the dash and the engine starter panels. Neither engine emergency cutoff switch does anything.

We have now run 16 lengths of brand new cable, for a start.

1. In the first pix, there is a row of three sending units, and a fourth can be seen underneath. What are they for? In the group of three, the middle one is busted.

2. The second pix is a sending unit on the bottom of the engine. Is this for reading oil temperature?

3. This third picture is an unidentified item. Would this be the kill switch?

Thanks in advance for all your enlightening responses!

Title: Re: Need help identifying these sending units.
Post by: Mex-Busnut on November 07, 2011, 12:15:15 PM
Let me clarify that in the third picture, I see a piston, and some kind of sending unit under that. I am wondering:

1. Is this piston the cutoff?

2. What is that sending unit do?

Thanks again!
Title: Re: Need help identifying these sending units.
Post by: luvrbus on November 07, 2011, 01:10:36 PM
The 3rd photo is of a Jake buffer switch under the old solenoid (top) from the old emergency shutdown that was on the old v71 Mexican engineering love it, no emergency shut off is needed for a 92 series.

Ist photo will be all for the temperature and shut down lights and gauges second photo is not clear but could a pulse generator for a tachometer


good luck
Title: Re: Need help identifying these sending units.
Post by: Mex-Busnut on November 07, 2011, 06:20:18 PM
Thanks, Luvrbus!

1. So can these be replaced with standard sending units?

2. Any idea where I can get wiring info?

Title: Re: Need help identifying these sending units.
Post by: Scott & Heather on November 07, 2011, 07:37:34 PM
Clifford strikes again. I seriously wonder if he has a bus tattoo. I was going to guess the first photo was alarm stat/idiot light sender. After that I was clueless  :-\
Title: Re: Need help identifying these sending units.
Post by: Busted Knuckle on November 08, 2011, 06:09:30 PM
Quote from: Scott Bennett on November 07, 2011, 07:37:34 PM
Clifford strikes again. I seriously wonder if he has a bus tattoo. I was going to guess the first photo was alarm stat/idiot light sender. After that I was clueless  :-\

Scott if you haven't already, you will discover Clifford is the YODA of buses and has probably forgotten more about buses than the rest of us will ever be lucky enough to learn! (and I assure you he's not forgotten much compared to what he knows!)
;D  BK  ;D
Title: Re: Need help identifying these sending units.
Post by: zubzub on November 09, 2011, 02:48:40 AM
Quote from: Mex-Busnut on November 07, 2011, 06:20:18 PM
Thanks, Luvrbus!

1. So can these be replaced with standard sending units?

2. Any idea where I can get wiring info?



see if they work first, temp senders tend to match the gage, so one of the temp senders may be functional with variable resistance, the other temp senders are probably on/off senders so it will be easy to test them if you pull them.  Basically one temp sender(the one to a gage) will present variable resistance to ground as it warms up.  the others (to light or buzzer) will either be on or off and when heated enough will then switch to off or on.
Can't help you with the wiring diagram, but if you work methodiaclly and make a diagram as you go it is not too hard to wire and engine, there just aren't that many wires....if you keep each basic component set seperated, it is possible to rewire a vehicle without getting lost ie; all engine control wires in one bundle, all gage and idiot light wires in the next, all rear lighting, etc...you then make a wiring diagram for each bundle....GM did it back this way in the 50's some car manufactures took longer....I have seen volvo diagrams form the 70's with everything on one sheet....what a mess.
   Speaking of which, if you cAN'T FIND THE WIRING DIAGRAMS FOR YOU BUS oops, try using the 4104 diagram (which is free online) as a template for the basics (it will still need editing as the 4104 had tons of extra wiring/engine shut down stuff that most don't use).