johnson 85ESL72R Control box Smokin!

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whatshisname

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Mar 31, 2010
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This week i fired up my 72 85 hp Johnson only to find smoke coming out of the shift box. opened it up and found the blocking diode "hot". bought a replacement fired it up and the insulation melted off the wires of the new diode. Any thoughts?
 
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F_R

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Re: johnson 85ESL72R Control box Smokin!

There must be an excessive current flowing through the diode.
That suggests a short circuit to ground in the shift circuit. Hm.m.m., wonder why the fuse doesn't blow?
 
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whatshisname

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Re: johnson 85ESL72R Control box Smokin!

Thanks for the info .... after the new diode wires (insul) melted i had nothing at the turn of the key. ithought maybe the switch fried too. After your post i located the fuse which broke when i tryed to remove it i looked like it blew.
I'd appreciate any advice on what to do nest

THANK YOU!
 
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whatshisname

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Re: johnson 85ESL72R Control box Smokin!

found more problems today, more bare wires (melted probably) under the horn inside the control box. seperated them and replaced the 30 A fuse with a 20A that i think is the proper size. turned the key and eventually blew the fuse. i disconnected the wires going down to the shift solonoids and tryed again with new fuse and everything seems to be ok. (at least the fuse didn't blow and nothin gets hot. I'm thinkin something could be shorted inside the
lower unit . Any advice on electrical testing without taking it apart?
 
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