Onan Still a Mystery

[mr.c]

Duane Simmons provided some of us at one of the rally's with a set of easy to
understand explanations of the onan. If you don't have one of these, let me know
and I can try to scan it and send it to you. It explains all the board parts in
a simple way. Or as an alternative, call Duane. He is an expert on the onan

Al Chernoff mr.c

> The GMC Maintenance Manual(s) I ordered arrived yesterday; about 10 pounds of
> them (3 volumes). $146.42 with S&H.
>
> I rushed to the section on the Onan, only to be disappointed by the
> incomplete, difficult to decipher, so-called schematics of the control system.
> However, I did find that the strake with no wire on my circuit board is pin
> #6, not pin #11. It supplies power to the lamp and RTM (running time meter),
> apparently from another #6 strake at the top of the board. If you think this
> sounds confusing, try reading section 24C, pages 47-49 in the X-7525B volume.
>
> Now if I can just figure out what happens when I press S3 to make current flow
> through K1 and K2 contacts and S3 to GND, maybe I'll be able to figure out
> where the cut wire from my starter motor solenoid is supposed to go to. By
> the time I get through with this project, I expect to be the world's foremost
> expert on Onan circuit boards.
>
> All I really wanted to know is where the original connection was for that
> #@%#*^&(^* wire that goes to the starter solenoid; not have to go to
> electrical engineering school.
>
> Does anyone know? The wire in question is the one connected to the inner
> terminal at the rear of the starter motor solenoid. It is a small wire, and
> that's the one that was cut.
>
> The starter motor solenoid has two terminals. The outer terminal has a heavy
> (#4?) wire going to it, presumably from the battery, plus a small wire that
> connects to the rear terminal on a solenoid switch just below the circuit
> board. That solenoid has 4 terminals; the front end terminal has 2 small
> wires going to it; the front side terminal has a small wire going to pin #7 on
> the circuit board; the rear side terminal has no wire; and the rear end
> terminal has 2 small wires going to it.
>
> Complicated? Seems like it, but probably has a real simple answer.
>
> Glenn

 

[dick kennedy]

Al,

I would also appreciate a copy of any info that you may have on the Onan.
The schematic in the book book is rather cryptic. Just a redraw of the
schenatic to make it more legible would be a big help. It's a pretty simple
circuit but the documentation is difficult to follow. Usually when I tackle
something like this I just start redrawing until I get it in a form where
the function is clear but I haven't had time to do that on this. Since I
haven't had time to do this myself I hope that someone else has.

On my unit the connections are corroded and all of the wiring is getting old
and marginal. This aspect was only one of the minor problems in my most
recent difficulties but I had to reconnect a broken wire on one of the
terminals and the big connector is marginal.

When I'm working on something like this I always apply a little dab of
vaseline to terminals or wherever there is corrosion. I've done this ever
since I was a kid and it seems to minimize future problems. (Nuts & bolts
get antisieze)

Thanks

Dick

>Duane Simmons provided some of us at one of the rally's with a set of easy to
>understand explanations of the onan. If you don't have one of these, let
me know
>and I can try to scan it and send it to you. It explains all the board
parts in
>a simple way. Or as an alternative, call Duane. He is an expert on the onan
>
>Al Chernoff mr.c
>

>
>> The GMC Maintenance Manual(s) I ordered arrived yesterday; about 10 pounds of
>> them (3 volumes). $146.42 with S&H.
>>
>> I rushed to the section on the Onan, only to be disappointed by the
>> incomplete, difficult to decipher, so-called schematics of the control
system.
>> However, I did find that the strake with no wire on my circuit board is pin
>> #6, not pin #11. It supplies power to the lamp and RTM (running time meter),
>> apparently from another #6 strake at the top of the board. If you think this
>> sounds confusing, try reading section 24C, pages 47-49 in the X-7525B volume.
>>
>> Now if I can just figure out what happens when I press S3 to make current
flow
>> through K1 and K2 contacts and S3 to GND, maybe I'll be able to figure out
>> where the cut wire from my starter motor solenoid is supposed to go to. By
>> the time I get through with this project, I expect to be the world's foremost
>> expert on Onan circuit boards.
>>
>> All I really wanted to know is where the original connection was for that
>> #@%#*^&(^* wire that goes to the starter solenoid; not have to go to
>> electrical engineering school.
>>
>> Does anyone know? The wire in question is the one connected to the inner
>> terminal at the rear of the starter motor solenoid. It is a small wire, and
>> that's the one that was cut.
>>
>> The starter motor solenoid has two terminals. The outer terminal has a heavy
>> (#4?) wire going to it, presumably from the battery, plus a small wire that
>> connects to the rear terminal on a solenoid switch just below the circuit
>> board. That solenoid has 4 terminals; the front end terminal has 2 small
>> wires going to it; the front side terminal has a small wire going to pin
#7 on
>> the circuit board; the rear side terminal has no wire; and the rear end
>> terminal has 2 small wires going to it.
>>
>> Complicated? Seems like it, but probably has a real simple answer.
>>
>> Glenn
>
>
>

>
>

 

[jim bounds1]

Yea, you hit it on the head when you said vague! Actually, they make it
much harder with their explaination than it needs to be. I haven't said
anything regarding your situation before now because I really like to
have more of a one on one when solving generator problems! A crossed
wire here or there will make things much worse! I've got a level 3 Onan
tech. working with me now. If you would like, call and I'll put him on
with you. 1-877-275-4462

>
> The GMC Maintenance Manual(s) I ordered arrived yesterday; about 10 pounds of
> them (3 volumes). $146.42 with S&H.
>
> I rushed to the section on the Onan, only to be disappointed by the
> incomplete, difficult to decipher, so-called schematics of the control system.
> However, I did find that the strake with no wire on my circuit board is pin
> #6, not pin #11. It supplies power to the lamp and RTM (running time meter),
> apparently from another #6 strake at the top of the board. If you think this
> sounds confusing, try reading section 24C, pages 47-49 in the X-7525B volume.
>
> Now if I can just figure out what happens when I press S3 to make current flow
> through K1 and K2 contacts and S3 to GND, maybe I'll be able to figure out
> where the cut wire from my starter motor solenoid is supposed to go to. By
> the time I get through with this project, I expect to be the world's foremost
> expert on Onan circuit boards.
>
> All I really wanted to know is where the original connection was for that
> #@%#*^&(^* wire that goes to the starter solenoid; not have to go to
> electrical engineering school.
>
> Does anyone know? The wire in question is the one connected to the inner
> terminal at the rear of the starter motor solenoid. It is a small wire, and
> that's the one that was cut.
>
> The starter motor solenoid has two terminals. The outer terminal has a heavy
> (#4?) wire going to it, presumably from the battery, plus a small wire that
> connects to the rear terminal on a solenoid switch just below the circuit
> board. That solenoid has 4 terminals; the front end terminal has 2 small
> wires going to it; the front side terminal has a small wire going to pin #7 on
> the circuit board; the rear side terminal has no wire; and the rear end
> terminal has 2 small wires going to it.
>
> Complicated? Seems like it, but probably has a real simple answer.
>
> Glenn