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• U1 U2 U4 U6 Debut Whatsa Matter U?

U1 U2 U4 U6 Debut Whatsa Matter U?

The U series appeared briefly. The U1 and U2 were used on some stationary engine installations, one being the 110 Volt Delco light plant. The U4 was used on some Fordson tractors. It looked like the drive end was pointing the wrong way. When in repair, they were a hot reliable magneto. As others with a wound armature, beware of sticky goo seeping from the armature. As always, check condensers for electrical leakage and make sure that the points have shiny smooth contacts and move freely. The breaker rocker pivot pins can grow corrosion and hang up or float causing an intermittent spark. If the armature is seized and not rusted solid, bringing the mag up to 250 or 300 degrees in the oven will make the goo let go. When they get gooey, it is time to rewind. Beware when removing the armature to remove the collector brush and the tiny pointy brass screw under the front housing pointing at the collector spool. It serves as a safety gap and will break the collector spool if not removed when removing the armature. 

Here is an introductory brochure with  some helpful service and parts information to keep yours alive and well.