Onan trouble shooting

Looks like my BRIDGE RECTIFIER just also went south.
I looked at the location of it. One screw may come out OK I hope. The wires i'm not so sure.
After I get the new rectifier I'll give it another look.

I've looked at a few on Amazon and fleebay.

I have a question.
would a 50A be better than a 25A?
Both are 1000v.
I assume so but we all know what that means.
--
1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
 
>
> Looks like my BRIDGE RECTIFIER just also went south. I looked at the location of it. One screw may come out OK I hope. The wires i'm not so sure. I have a question. would a 50A be better than a 25A? Both are 1000v. I assume so but we all know what that means.

There is only one screw in it if it is the original.

The bridge delivers 4A to the field assembly at full load. A 1kV 25A replacement is fine. Don’t assume things when it comes to engineering.

Be EXTREMELY careful with the wires as you pull them off the old bridge. Label them and do not flex nor pull on them any more than necessary.

Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
 
Mike,
You can reach out to me as when you get the part, it will not fit the
plastic housing.

On Wed, Jun 19, 2019 at 6:29 PM Jim Miller via Gmclist <

> > On Jun 19, 2019, at 9:22 PM, Mike Hamm via Gmclist <

> >
> > Looks like my BRIDGE RECTIFIER just also went south. I looked at the
> location of it. One screw may come out OK I hope. The wires i'm not so
> sure. I have a question. would a 50A be better than a 25A? Both are 1000v.
> I assume so but we all know what that means.
>
> There is only one screw in it if it is the original.
>
> The bridge delivers 4A to the field assembly at full load. A 1kV 25A
> replacement is fine. Don’t assume things when it comes to engineering.
>
> Be EXTREMELY careful with the wires as you pull them off the old bridge.
> Label them and do not flex nor pull on them any more than necessary.
>
>
> Jim Miller
> 1977 Eleganza
> 1977 Royale
> Hamilton, OH
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
> Here's an excellent troubleshooting guide for Onans: https://www.flightsystems.com/troubleshooting/

Quite a bit of that document - in particular the control board operation and generator section description/troubleshooting - is not at all valid for the Onans used in the GMC coaches and could cause confusion and frustration for a GMC owner.

Duane Simmons and several others have written very good troubleshooting documents that are directly applicable to the NH and BF models found in our GMCs.

I have installed Flight Systems’ control board on several GMC Onans including my own and am happy with it. I have not (yet) seen it exhibit the smoked relay/smoked resistor failure mode related to the run latch circuit that some Dino boards have suffered.

—Jim
Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH
 
We have been supplying the Dyno Boards for few years and have not run into
any issues at all in the last couple years.
We must supply at least 60-80. Units a year and our customers know we
extend the warranty for three years or more as I feel an average owner does
not use the Mh that much.
We also give technical support to All callers.

On Fri, Jun 21, 2019 at 5:40 AM Jim Miller via Gmclist <

> On Jun 21, 2019, at 8:20 AM, Todd Snyder via Gmclist <

>
> > Here's an excellent troubleshooting guide for Onans:
> https://www.flightsystems.com/troubleshooting/
>
> Quite a bit of that document - in particular the control board operation
> and generator section description/troubleshooting - is not at all valid for
> the Onans used in the GMC coaches and could cause confusion and frustration
> for a GMC owner.
>
> Duane Simmons and several others have written very good troubleshooting
> documents that are directly applicable to the NH and BF models found in our
> GMCs.
>
> I have installed Flight Systems’ control board on several GMC Onans
> including my own and am happy with it. I have not (yet) seen it exhibit the
> smoked relay/smoked resistor failure mode related to the run latch circuit
> that some Dino boards have suffered.
>
> —Jim
> Jim Miller
> 1977 Eleganza
> 1977 Royale
> Hamilton, OH
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
I got the new BR 50a 1000v from Amazon 3for $7.00.

One problem that may not matter, the original BR has marking for AC but not for + and -.
Everyone that i have seen has a marking but that Onan part does not.
Does the + and - matter with this?
50/50 chance i may just give it a try.
--
1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
 
It does matter

On Sat, Jun 22, 2019 at 2:42 PM Mike Hamm via Gmclist <

> I got the new BR 50a 1000v from Amazon 3for $7.00.
>
> One problem that may not matter, the original BR has marking for AC but
> not for + and -.
> Everyone that i have seen has a marking but that Onan part does not.
> Does the + and - matter with this?
> 50/50 chance i may just give it a try.
> --
> 1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
"Duane Simmons and several others have written very good troubleshooting documents that are directly applicable to the NH and BF models found in our
GMCs."

That's great!

But where are they?
--
Todd Snyder, Buffalo NY
1976 Eleganza II
 
I went with the bent pin method to keep that white connector.
Didn't work on the first try. Rotated 180 deg and all is good.

--
1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
 
> "Duane Simmons and several others have written very good troubleshooting documents that are directly applicable to the NH and BF models found in
> our GMCs."
>
> That's great!
>
> But where are they?

Here's a link from b'dub's page... https://www.gmcmi.com/generators/ Lots of almost anything you might want on the Onan. Duane Simmons is among
them. This is one from GMCWS http://gmcws.org/Tech/dsimmons/onan/onan.html specifically on the control board.

Most of it is beyond me at this point in time... But I'm getting there.
--
Deb McWade
Logan Lake, BC, CAN
"Li'l Sister"
'77 Kingsley, 403, EBL EFI;
TZE167V101404
It's Bigger on the Inside!
 
There are few newer trounlevshooting steps that the H

On Sun, Jun 23, 2019 at 8:47 AM Deb McWade via Gmclist <

> > "Duane Simmons and several others have written very good troubleshooting
> documents that are directly applicable to the NH and BF models found in
> > our GMCs."
> >
> > That's great!
> >
> > But where are they?
>
> Here's a link from b'dub's page... https://www.gmcmi.com/generators/
> Lots of almost anything you might want on the Onan. Duane Simmons is among
> them. This is one from GMCWS
> http://gmcws.org/Tech/dsimmons/onan/onan.html specifically on the control
> board.
>
> Most of it is beyond me at this point in time... But I'm getting there.
> --
> Deb McWade
> Logan Lake, BC, CAN
> "Li'l Sister"
> '77 Kingsley, 403, EBL EFI;
> TZE167V101404
> It's Bigger on the Inside!
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
Sorry, I slipped my finger on my phone.
There are more issues that come up as the units get older.
One is lower oil pressure as they units get older.
Core for that is to replace pressure sender with a lowevrsted sender.
Lot of the units no longer have the rubber air seal around the oil filter.
I know back in 1980 we were told how important they are.
Also the hot cooling are deflector as it serves to do two function; to keep
air from blowing dirt and drawing it through the armature and field and
sand blasting them.
We now have a Catalitic Muffier for them so it avoids the smell we get as
these Onan does no burn clean. People love them as it doesn't send out
offensive odor.

> There are few newer trounlevshooting steps that the H
>
> On Sun, Jun 23, 2019 at 8:47 AM Deb McWade via Gmclist <

>

>> > "Duane Simmons and several others have written very good
>> troubleshooting documents that are directly applicable to the NH and BF
>> models found in
>> > our GMCs."
>> >
>> > That's great!
>> >
>> > But where are they?
>>
>> Here's a link from b'dub's page... https://www.gmcmi.com/generators/
>> Lots of almost anything you might want on the Onan. Duane Simmons is among
>> them. This is one from GMCWS
>> http://gmcws.org/Tech/dsimmons/onan/onan.html specifically on the
>> control board.
>>
>> Most of it is beyond me at this point in time... But I'm getting there.
>> --
>> Deb McWade
>> Logan Lake, BC, CAN
>> "Li'l Sister"
>> '77 Kingsley, 403, EBL EFI;
>> TZE167V101404
>> It's Bigger on the Inside!
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.appliedgmc.com
> 1-800-752-7502
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
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