Bukh DV 10 - Switching Off

[spiller]

On purchase of 1980 Superseal, the switch panel had been "bastardised" and "switch off" was routed to a sprung switch.
The switch eventually went through the panel, one day, and an entire replacement panel and switch was purchased which required some careful thought in the rewiring of such ie back to original.
Pos 1 is Switch Off
Pos 2 is Off
Pos 3 is "Off"
Pos 4 is On with warning lights lit
Pos 5 is Start

To switch off ie Stop the engine, Pos1 is selected and usually works, but occasionally it doesn't and I suspect that there is a thermal input to this which prevents switch off while over a certain temperature (as this usually occurs after engine has been working hard).

Simple question - Am I correct, or is there another explanation?

Thanks in anticipation

 

[pvb]

Position 1 on the key switch just activates a stop solenoid. Don't think it's interlinked with temperature sensor. Could be sticky solenoid, or bad connection at stop solenoid, or in fuse panel which feeds it. There's a wiring diagram in the owner's manual, downloadable here.

 

[fibz99]

My original bukh manual was lost in the dusty past, thanks for that.

 

[oldharry]

My DV 20 the stop solenoid is activated by the switch with no interlinking anywhere.

Suspect 1 is the wiring - they take a surprisingly high current. Suspect 2 is the solenoid itself sticking when the engine is hot.

The manual comments that the stop solenoid must be set very precisely to work:

"Tighten the four fixing screws evenly. At the slightest disalignment due to the tightening the stop magnet will not work."

The precise length of the operating rod is adjusted by the large nut behind the cover. The manual unhelpfully says this must be adjusted to the same length as the one being replaced.... /forums/images/graemlins/frown.gif

 

[Twister_Ken]

I'll look in my DV10 manual later on today, see if it says anything useful - it's very rudimentary.

 

[philip_stevens]

I had a DV20 in our previous boat, and I inadvertently left the switch in the "stop engine" position, and burnt out the solenoid. The new one cost another "leg" (ref:arm and leg).

The solenoid also limits the top revs of the engine. So must be set up very precisely.

I quote from the manual.
"Stop Magnet - Make, Bosch Type: 0330 101 024.
In case of defects on the stop magnet, which cannot be repaired, the stop magnet must be replaced. When mounting a new stop magnet observe the following.

1. Tighten the four fixing screws A evenly. At the slightest disalignment due to the tightening the stop magnet will not work.

2. The stop button, which is activated by the stop magnet, determines the maximum position of the fuel pump control rod. Therefore, it is necessary to check that the distance X, which is adjustable by the nut B, is the same as the stop magnet previously used.

This is done easiest by dismounting the stop magnet together with the cover C."

If you need a copy of the drawing, email me with a PM.

 

[Twister_Ken]

From the book of words

The manual shows 5 switch positions, a-e. I'll use clock convention to describe them.

a. (1200) Switched off. The position before insertion and removal of the key.
b. (0100) Warning and instrument lights are alight
c. (0200) Thermostart (preheat?)
d. (0300) Start
e. (1100) Engine Stop.

Notes:
In order to reach positions d and e the key body must be depressed by means of the key
The switch should not be left in position e because of the heavy consumption of current by the stop solenoid.
The alarm functions are tested in position e
The starter must not be operated for more than 10 seconds. If further operation is necessary a pause of at least half a minute must be made before starting attempt is repeated.

There's also an immensely complex wiring diagram which mean ugger ball to me.

Does this do anything to help?

If not, PM me with a specific question and I'll see if the book has an answer.

 

[Twister_Ken]

Re: From the book of words

On procedure for turning off the book says:

1. Reduce the load gradually in the course of 15-20 mintes before stop
2. Reduce engine to idling and gear is put in neutral position
3. Turn the ignition key left to stop position, pushing it inwards slightly. The key must not be left in this position once the engine has stopped due to large current consumption of the stop solenoid. In this position, the acoustic alarm will function when the engine has stopped.

There's nothing at all about a 'hot stop' preventer. Maybe the secret lies in 'pushing it inwards slightly'.

 

[spiller]

Re: From the book of words

Thanks to all of you.

At least I have some confidence now.

When the key wont switch it off,I have resorted to the decompressor. I have been advised that this is not a good move. If so, why?