Problem with diesel "kill" switch!

Hello,
I recently purchased a boat with a BMW D150, 6 cylinder, turbocharged marine diesel. The wiring was a mess and when I attempted to clean it up I created a problem with the ignition system. The “kill” switch is a lighted two position switch with three terminals 1 marked ground, 2 marked Acc, 3 marked power. When I remove and meter the wire going to the fuel injection pump, I get continuity to ground. When I put it together with 1 to ground, 2 to the pump and 3 to 12 volts it blows the fuse. The wire to the pump connects to a part described as a magnet not a solenoid. The wiring examples I found in Payne’s book only have 2 connections on the switch and all go to a solenoid. The electrical schematic in the shop manual is written in German and the tiny English sub print is illegible, the information in it in regards to this circuit is vague anyway. It did show an 8amp fuse protecting the circuit and the one that was installed and blown was a 15 amp. How can I test to see if I damaged the magnet?
Any help is greatly appreciated.
Thanks, Michael

 

Interesting problem.

Have you tested the solenoid directly from the battery, completely bypassing the switch? I think that’s the first thing I would do. Maybe with an inline fuse to avoiding the arc-welding practice. I also think the “magnet” is just an electro-magnet, which we can still call a solenoid. Do you agree?

Let us know what happens with that test, then on to the switch.

Mike

 

Thanks Mike

Thanks for your reply Mike.
Yes, I agree that the magnet could be called a solenoid. The switch will be replaced anew in short order due to the mishap of letting the magic smoke out . You know, the smoke that makes electrical things work. You don’t even want to know about the attempted vcr/dvd repair. lol just kidding but I am capable and accomplished at the letting of magic smoke. I will try hooking a protected current to the solenoid but I fear that it will just blow the fuse. I suppose that will tell me if the solenoid is also burnt toast. There is no plunger or anything to watch move but it will be a good sign if it takes the current. merCruiser now deals the BMW marine product and you can bet, I will be in touch with them.

 

Good news update,
I wired from 24v to an inline fuse then through a new switch to the solenoid and yippy-ki-ay she started right up and purred like a kitten. Strange thing is and still a mystery to me is that before I smoked the old switch I had checked it with a meter for proper continuity. The only thing I can think is that it was shorting out under a load. I guess that the switch was the problem all along. From now on I will test switches with a current instead of just continuity.
Thanks for your help,
Michael