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American Bosch FB1ED1

TomBall

Subscriber
Last Subscription Date
12/25/2018
I have been working on an American Bosch FB1ED1 mag that I was going to try on my 10 HP Novo. I think the mag that shoul d be on it is a DU1. The FB1 is a mag that apparently was used on a marine engine and has a lever that changes point opening timing. I have great spark when the impulse trips and you can spin it by hand and also get good spark. When I put it on the engine, I only get spark when the impulse trips. I can't spin the engine fast enough to get the mag to spark without the impulse tripping. I know that the engine will run faster than I can crank it but I do have it set up to run slowly. Is it possible that this mag will not produce spark at the slow speed of a hit miss engine?
 

Junkologist

Subscriber
Last Subscription Date
12/28/2019
Have the magnets had a fresh charge? It usually takes very little rotational speed to get a good spark out of an old Bosch mag when everything is up to snuff.
 

TomBall

Subscriber
Last Subscription Date
12/25/2018
Yes, I have charged the magnet. The spark is hot at all speeds except slow
 

Kirk Taylor

Registered
I have been working on an American Bosch FB1ED1 mag that I was going to try on my 10 HP Novo. I think the mag that shoul d be on it is a DU1. The FB1 is a mag that apparently was used on a marine engine and has a lever that changes point opening timing. I have great spark when the impulse trips and you can spin it by hand and also get good spark. When I put it on the engine, I only get spark when the impulse trips. I can't spin the engine fast enough to get the mag to spark without the impulse tripping. I know that the engine will run faster than I can crank it but I do have it set up to run slowly. Is it possible that this mag will not produce spark at the slow speed of a hit miss engine?
Tom,
Have you tried it at different positions on the advance/retard. That changes the point opening time in relation to the armature position. There is an optimal armature position for point opening; either side of that will give a weaker spark.

Kirk
 

TomBall

Subscriber
Last Subscription Date
12/25/2018
I just had a detailed response wiped out by the computer, so this will be short. I have it set to open the points at maximum impulse. Wish I had a DU1 to try.
 

cobbadog

Registered
I'm not sure if I understand your issue.
The impulse is there so you can turn the engine slowly and get a good spark.
But you say you "can't spin the engine fast enough to get the mag to spark without the impulse tripping" the impulse should not trip when it is going fast.
Sorry if I am confused.
The other thing is how slow are you cranking the engine to get no spark?
 

TomBall

Subscriber
Last Subscription Date
12/25/2018
I fully understand that the impulse won't trip when the engine is running. What I stated was that if you turn the mag at a slower speed by hand without the impulse tripping, it will not spark. You have to turn it quite fast by hand to get a good spark. I'll just put some gas in the carb bowl and see if the engine will run fast enough for the mag to produce spark
 

Paul Ellzey

Subscriber
Last Subscription Date
01/04/2019
Can someone PLEASE tell me what magneto will bolt up to a NOVO Rollr TU engine. It has a wico on it now that is dead. no identifying model or type. Someone removed the serial number and ID plate on it. it is a base mount.
 
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