Farm Equipment - Magneto

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Magneto

Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=202099
Printed Date: 23 Nov 2024 at 6:02pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: Magneto

Posted By: Kiwi
Subject: Magneto
Date Posted: 03 Jul 2024 at 5:05am

Hi all what would make a Bosch magneto go bad one minute I hav spark next none what do I need to look for is it the points or condenser or coil any help would be greatly appreciated

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Tractors Allis EB,two C,diesel G

Replies:

Posted By: steve(ill)
Date Posted: 03 Jul 2024 at 9:02am

condenser are the most common failure for cutting in and out when cool or hot....... A COIL will work when COLD, then cutout when HOT.. or fail completely .... if the point face is clean, you should not have a problem with it.

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Like them all, but love the "B"s.

Posted By: ac fleet
Date Posted: 04 Jul 2024 at 8:15am

I DESPISE mags! ---- The biggest problem I run into is the coils are dead. I have also been told that the magnet bars inside the coils can lose charge and make a rebuilt mag go dead if not checked or recharged.

I am fighting one right on a bubcat 500 skidder and to take the mag off you have to take the motor out! Talk about stupid!!!!!!!!!!

This thing is about 1 step from getting dumped in the hole and buried with a bunch of other stuff.

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http://machinebuildersnetwork.com/

Posted By: Alberta Phil
Date Posted: 04 Jul 2024 at 8:55am

First I would check the points for corrosion and clean them. Just a little on the point faces could cause intermittent spark. Also, check point gap-- should be at about .020. I've got a lot of tractors with mags and find them pretty reliable. Never had to replace a condenser yet. Old coils can break down and have internal shorts in the windings, but in my experience, if the coil is bad there will be no spark.

Posted By: ac fleet
Date Posted: 04 Jul 2024 at 3:28pm

Never had a mag here yet that would ever work!--- changed all that I could over to dist. and the ones I cant change, get external coil hooked to 12-v batteries . Even then you are stuck with a stupid mag. but at least the coil problem is solved.

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http://machinebuildersnetwork.com/

Posted By: steve(ill)
Date Posted: 04 Jul 2024 at 3:37pm

most of these mags have been around for 50- 75 years.. the trouble with the ones that doen work is OLD BEAT UP PARTS... I have bought a couple new coils and a few condensers and ahve 4-5 of them working right now. i had one that had week throw our springs on the impusle weights and caused me some starting problems.... one of the BEST things i ever did was buy a COMPLETE REBUILD UNIT from one of the Vendors on this site. It had a new coil, NOS condenser and point and remagnetized magnet/ rotor and new parts in the impulse... It is basiclly NEW UNIT and works GREAT... Tractor fires up on 1 revolution of the motor and never misses a beat..... OLD WORN OUT PARTS are the cause of almost ALL magnito problems.

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Like them all, but love the "B"s.

Posted By: ac fleet
Date Posted: 05 Jul 2024 at 9:38am

The one I am fighting right now is in a bubcat 500 skidder. mag looks new inside,---no spark, cant get mag off without taking the air shroud off and to get it off motor gotta come out of the loader! YA! aint gonna happen on my watch! Probably end up shovin the thin in the hole and bury it along with other stuff!

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http://machinebuildersnetwork.com/