1986 740GLE TurboDiesel Ignition Switch????

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fred - 26 Feb 2006 21:36 GMT

Anyone, please.

The diesel fuel injection is mechanical and there's no electrical fuel
pump. The engine is a diesel so there's no ignition system involved
once it's running.

SO when one switches OFF the 'ignition switch', the engine stops.
Therefore what is the control that the 'ignition switch' turns off??
It must be something electromechanical?? Anyone know the details of
how all that works??? Is there a fuse in this chain??

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M-gineering - 27 Feb 2006 07:40 GMT

> Anyone, please.
>
[quoted text clipped - 6 lines]
> It must be something electromechanical?? Anyone know the details of
> how all that works??? Is there a fuse in this chain??

there is a solenoid on the diesel injection pump (look for a single
(brown?) wire

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---
Marten

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fred - 28 Feb 2006 01:20 GMT

Does this engine use an electrical fuel pump? A Chilton shows possibly
two electrical fuel pumps for the turbo diesel. Anyone, please.

> > Anyone, please.
> >
[quoted text clipped - 9 lines]
> there is a solenoid on the diesel injection pump (look for a single
> (brown?) wire

Thanks.

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Peter K L Milnes - 28 Feb 2006 02:12 GMT

The only electrical fuel device is the fuel solenoid mounted in the pump.
This has a wire which is energised with ignition "on" and enables high
pressure fuel to reach the fuel distributor on the end of the pump. The only
warning re this device is do not rev the engine as you switch off. The
solenoid will be sucked down onto it's seat and you will not be able to get
it to release until you take it out of the pump and clean/free-up/replace
the solenoid. The only fuel pump is the mechanical one. I had thought of
putting a small one at the tank outlet as a backup for when the fuel runs
out before you can refuel. Perhaps Chilton refers to the 850 series and
later diesels which have electronic fuel control and can be "chipped" to
produce similar power/torque increase to tuniong the mechanical pump.

All the best, Peter.

700/900/90 Register Keeper,
Volvo Owners Club (UK).

> Does this engine use an electrical fuel pump? A Chilton shows possibly
> two electrical fuel pumps for the turbo diesel. Anyone, please.
[quoted text clipped - 14 lines]
>
> Thanks.

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fred - 28 Feb 2006 21:49 GMT

> The only electrical fuel device is the fuel solenoid mounted in the pump.

Any chance of a picture, diagram or precise description of exactly
where that solenoid is located? How does the wire attach and how does
the wire get there(bundling/routing)?)

> This has a wire which is energised with ignition "on" and enables high
> pressure fuel to reach the fuel distributor on the end of the pump. The only
> warning re this device is do not rev the engine as you switch off. The
> solenoid will be sucked down onto it's seat and you will not be able to get
> it to release

Are you saying the solenoid will be stuck in the on(run engine) or off
position??

> until you take it out of the pump and clean/free-up/replace
> the solenoid. The only fuel pump is the mechanical one. I had thought of
> putting a small one at the tank outlet as a backup for when the fuel runs
> out before you can refuel. Perhaps Chilton refers to the 850 series and

Chilton (8786) 72300 clearely shows in figure 120 on page 6-86 two
electric fuel pumps...but I've seen ambiguous and erroneous Chilton
stuff before.

> later diesels which have electronic fuel control and can be "chipped" to
> produce similar power/torque increase to tuniong the mechanical pump.
[quoted text clipped - 22 lines]
> >
> > Thanks.

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Peter K L Milnes - 01 Mar 2006 02:48 GMT

Solenoid will be stuck in off position. If you look at the adjustment tower
on the top of the pump the solenoid position is in front of the tower on the
main body. The wire (may be part of a loom if EGR is fitted) routes between
the pump and the block from below (loom may be attached to dipstick
support).

All the best, Peter.

700/900/90 Register Keeper,
Volvo Owners Club (UK).

>> The only electrical fuel device is the fuel solenoid mounted in the pump.
>
[quoted text clipped - 49 lines]
>> >
>> > Thanks.

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