Bosch ZU4 Magneto

Today I dragged out one of the old magnetos that belonged to Dad's old Morris Cowley from over 60 years ago. It had a tiny bit of spark but was a bit dirty all over and inside. There are all sorts of numbers stamped under the base and I have no idea what they mean, maybe copyright numbers. After doing a quick clean up and gaping the points to 0.020" which maybe a bit wide, not sure I got a slightly better spark. I tried my best to get the last of the old HT leads out but I cannot undo the screw locking it in place as the groove is stripped out and at the moment I have no idea how to get it out. Again I'm not sure what the little round window is for just above centre of the dizzy cap. Directly behind it is the rotor button which has a small circular recess in it with a very narrow raised section in the circle. Just above this circle and out of sight of the window is the spring loaded carbon brush.

Any ideas?

So I hooked up the magnetiser and sat the maggy in place and gave it 3 good zaps and instantly I could feel a stronger resistance as I turned it over by hand. Even doing this by hand and slowly it made a good spark. So out came the battery drill and gave it a steady but slow drive and then a faster one and the spark missed a beat every now and then but I put that down to the filth on the body where the spark was suppose to jump. End result is in the video clip along with some pics.

View:



P.S. Not sure if I mentioned that I bought a small compass to identify the N & S poles of the magnetiser and the magneto as well but somehow, possibly left it too close to the magnetiser when I was charging some screw drivers I reversed the polarity of the compass. (I know, I'm a genius), but with the help of good old YouTube I have now corrected this stuff up and it now points North again.

Morris

I have the manual for the ZU4/DU4. I think they are the most common magneto of the pre-30 era. If you want something give me a shout.

A have a few that look pretty good including an unused fully overhauled one with a rebuild receipt for $650.

I had these on both my 1907 ITALA and 1915 Willys-Overland.

I became an expert rebuilding these on the Peking to Paris but eventually the tiny roller bearings gave up and they flopped around shorting out. We finished with a coil and condenser from a Lada just using the magneto points as a distributor.

Lang

Lang, thank you for your reply. Not sure if the manual is in PDF form but if it is could I please have a copy?
On the advance and retard there is a short raised section near the clip that holds the cap in place. What is this for?

I am about to start on the Lucas magneto that also went on the same car but at the moment it is totally dead so I will work my way through it and start testing condensor and coils and point gap. This one also has one stripped screw for the HT lead and is stuck solid at the moment. I have it soaking in some Lanox overnight.

Point gap 1/64 inch and plug gap 1/50 inch.

Sorry Cobba got Morris' name in there somehow.

From memory the raised bit is a rough guide to put the cap back where it came from. I will have a look at one of mine to see if it jogs my memory.

Just ask me what you want because I have the huge manual of every electrical system (full wiring diagrams) for every car up to 25? I am sure there will be Lucas stuff in there. Give me the numbers.

Lang

Lang I wondered how my name got a mention but all is now revealed. I have heard of and I think seen Morrises with Bosch ( I don't know if American or German, but mine has a Lucas G4 (I think, without looking at it/them).

If this is not enough I can't help further!

oldcroak.com/bosch-du1-du2-du4-du6-early-pre-ww1/

oldcroak.com/zu4-zu6-zf4-zf6/

And looks like the DU and ZU both came out in 1911

www.old-engine.ch/files/magnetzuender_bosch.pdf

Thank you so much for the links and pages for the Bosch. The Lucas is a G4 but will double check it tomorrow. I feel I will need to delve quite deep into the Lucas magy nick named by members on the engine Forum as the Prince of Darkness. I want to prove them wrong.

Cobba, I wonder if they are the part numbers for the bits which make up that magneto. On our old DC motors at work, all the part numbers for armature, field coils, brushes and holders, etc are stamped (although on a plate)

Lang, you're a trove of information!

Jarrod.

O Yes
the magic word 'LUCAS'




A4 Printer Friendly to nail up on the wall

LOL
cya