B100l 10hp 80's Honda no spark

JohnVH

Seaman
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Sep 6, 2010
Messages
72
I just acquired the motor not running, mid 80's. It seems to have no spark. I have new plugs coming, it had ngk d5hs plugs, pretty black. I have a set of dr5hs coming, I read that the non r plugs may cause problems?

Anyway. Is there some info on testing the electronic parts before just throwing parts at it? Not having much luck searching the Internet.

Thanks
John
 

Alumarine

Captain
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Feb 22, 2005
Messages
3,684
It can be very difficult to see the spark on some of those motors.
You virtually have to be in a pitch black environment to see the spark.

If you determine that there is spark then I'd guess the carb is gummed up.
That's a very common issue and requires a proper cleaning. Usually several the first time you do it!
 

JohnVH

Seaman
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Sep 6, 2010
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Thank you. Starting fluid won't even make it pop. I'll have new plugs Tuesday and will check spark again. I have a tester but couldn't see anything happening.
Appreciate the help.
 

JohnVH

Seaman
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Sep 6, 2010
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72
New plugs in, wont even pop on starting fluid.

Anyone have info on how to text the electronic parts? Been looking for days and cant find anything.
 

Sea Rider

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Sep 20, 2008
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12,345
Will need to get a Honda Service Manual to check electrical specs to troubleshoot every electrical component with a good analog or digital multimeter to find which part is causing trouble...

Happy Boating
 

JohnVH

Seaman
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Sep 6, 2010
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I have the multimeter, I was hoping someone had a book and could just tell me so I didnt have to wait longer... Someone out that has to have a manual with that info..
 

Rick Stephens

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Aug 13, 2013
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I bought the service manual for the BF75, BF100, BF8 motors for $35 off Amazon years back. Doesn't look like they have it listed any longer, but Honda Power Equipment Publications is still around and they were who sold them on amazon. You might call them - 770-497-6400
 

Alumarine

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I can't help with the manual but you could check to see if the kill switch or in gear switch is not causing it not to fire.
I would disable both and see.
 

JohnVH

Seaman
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Sep 6, 2010
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72
I can't help with the manual but you could check to see if the kill switch or in gear switch is not causing it not to fire.
I would disable both and see.


I thought of that too, have not found the in gear switch, but unhooked the kill switch, no dice yet. The guys I got it from said a few months ago it was fine, would something go bad from sitting?
 

Alumarine

Captain
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Feb 22, 2005
Messages
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The gear shift switch is activated by a cam on the horizontal shaft of the gear shift I believe.
It's a blue wire and a black/white on mine.
 
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