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JLG 40H w Ford & Zenith carb: choke electric characteristics?

BrownBear

Member
Joined
Jan 28, 2020
Messages
10
Location
Wawa, Ontario
Got a Zenith 15080, Ford part # F8JL-TA, with an electric choke. Removing the carb for cleaning, the choke terminal thumbscrew was seized and trying to force it loose I felt something snap inside the choke. Opening it I found fragments of a plastic stop for the terminal bolt head and two very delicate coils one of whose leads was ripped off. I gingerly stretched out a couple loops of the broken coil to fashion a new lead and used a blob of epoxy to take the place of the stop (see photo).

I don't really understand the operation of this electric choke but presumably those coils are heating elements. I feel a bit unsure about my hack but thought I could at least compare its electrical characteristics against spec. I measure 16 ohms between the terminal and ground, seems like that's the resistance of the two coils in series. I thought I saw the expected resistance in a troubleshooting doc somewhere, but can't find it now. Does anyone know what resistance a good electric choke circuit should present?
 

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BrownBear

Member
Joined
Jan 28, 2020
Messages
10
Location
Wawa, Ontario
At ambient temp 65F, if I apply 12V to the terminal, the choke gradually goes from fully closed to fully open in about 1 minute. Seems qualitatively right anyway according to my reading on electric+bimetal chokes, so I'm going to call this a successful repair.
 

walkerv

Senior Member
Joined
Jan 21, 2016
Messages
1,125
Location
wingate nc
At ambient temp 65F, if I apply 12V to the terminal, the choke gradually goes from fully closed to fully open in about 1 minute. Seems qualitatively right anyway according to my reading on electric+bimetal chokes, so I'm going to call this a successful repair.
Sounds about rite to me and if your repair breaks well you got a link for parts now
 
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