Sat Feb 1 05:11:55 1997 - Message No. 340
From: Marcel_Sieling@kr.maus.de (Marcel Sieling)

Subject: Fuel pump


Hi,

>Now to the AT-diagram:
OK. [getting all of my engineering knowledge out of the back of my head] ;-)

>Here you have also the fuel pump and the preasure switch
Aeh, I may correct you: This is not a pressure switch, it is a fuel cut 
relay. It has no pressure sensor(!). So it is different from the Yamaha.

>and the CDI black box
Yes.

>The fuel pump is connected on one side directly to ground (G).
Correct...

>The 2nd cable (+12V (Bl/Bu)) is going to the switch I mentioned above
To the relay, yes.

>On this switch are 2 more cables (Bl/R and Bl/Y).
         ^^^^^^ relay
You're right.

>is connected to fuse "D" in the fuse box and also the the start/stop
>switch.
Correctly: Power is supplied via the ignition switch, which you operate 
using the key. This supplies the voltage for the fuel cut relay, whitch 
operates the pump. Without ignition no fuel pumping.

>From the other side of the start/stop switch it is going to several
>points on the diagram
It goes past a fuse to the battery.

>(Bl/Y) is going to the CDI.
>The question now, does somebody know what the CDI does?

Yes. It operates the motor (good joke ;-). Seriously: The B/Y cable 
operates two of the four ignition coils. So it delivers a pulse signal, 
which is dependent on the rate of revolution (Drehzahl). BTW: This signal 
also goes to the tachometer (Drehzahlmesser) at the cockpit.

>My idea is to connect the preasure switch directly to the ignition. As
>soon as you turn the key, the fuel pump is running and contolled by the
>preasure switch (same as FZR 1000). So you do not need a time relais.

This would be very bad IMHO, because at times, where ignition is on and the 
motor is not running, (in front of the ice shop e.g. ;-)) the fuel pump 
would continue pumping the fuel into the carburetor. Unexpectend things 
could happen. ;-)

>Is somebody expirienced enough, to tell me what functions are in the CDI
See above. (At least, what concernes the Black/Yellow cable).

I do not exactly know, how the time relay is installed (does anybody have 
an exact description? Please post it here!) but I think, Stefan, your way 
of changing the installation will cause more problems than solutions. ;-)

If nobody posts here the time relay application, I will try a provisory 
installation, where I connect the Black/Blue cable going from the relay to 
the pump directly (via a small pushbutton) to the ignition cable 
(black/red). So I can operate the fuel pump if I want and check, if it 
helps. If that works, I'll install that time relay (every car with fuel 
injection has that, e.g. listen to the back of a mercedes when the ignition 
is switched on and notice the short running of the fuel pump).

It would be very interesting, if anybody could post here the circuit layout 
of that time relay and explain how it is connected to the @ wiring.

take care - Marcello (rrr#52, ATIC#9, 13,486% Squid, KotFBL - Africa Twin)


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