gmclist@list.gmcnet.org

GMC Motorhome Discussion List

View all threads

Who loves and understands their Original Onan ?

DS
dave silva
Fri, Sep 18, 2020 1:27 AM

Seems like most of the generator talk on this and other GMC forums is 'what to replace it with'

I became pretty enamored with the Onan CCK that came with my Revcon.  The coach has not moved in a long time  but every couple years a hurricane
threatens us and i get the Onan running and it runs FOR DAYS. Then i forget about it for another couple years.

My recently acquired Birch needed a generator.  I found an Onan Emerald 1 that will just fit with minor mods and should still use the power drawer
rails.

The guys on Smokstack.com understand these things at a very deep level.  THrough them i've had no trouble keeping my old CCK running and getting my
head around the Emerald.

From what i understand, the Power Drawer is not unique. Onan made a whole bunch of them with a different carb configuration.

Of course there are quieter more fuel efficient gensets but they ain't cheap and it seems like with a little patience the Original can be made ot work
pretty well.

Just curious if there other fans of the green anchor.

--
Dave & Ellen Silva

1972 Revcon Olds 455, toro drive train. All Stock

Seems like most of the generator talk on this and other GMC forums is 'what to replace it with' I became pretty enamored with the Onan CCK that came with my Revcon. The coach has not moved in a long time but every couple years a hurricane threatens us and i get the Onan running and it runs FOR DAYS. Then i forget about it for another couple years. My recently acquired Birch needed a generator. I found an Onan Emerald 1 that will just fit with minor mods and should still use the power drawer rails. The guys on Smokstack.com understand these things at a very deep level. THrough them i've had no trouble keeping my old CCK running and getting my head around the Emerald. >From what i understand, the Power Drawer is not unique. Onan made a whole bunch of them with a different carb configuration. Of course there are quieter more fuel efficient gensets but they ain't cheap and it seems like with a little patience the Original can be made ot work pretty well. Just curious if there other fans of the green anchor. -- Dave & Ellen Silva 1972 Revcon Olds 455, toro drive train. All Stock
JH
James Hupy
Fri, Sep 18, 2020 1:49 AM

Properly maintained, they will outlast their owners and their coaches. I
would not get rid of one that was working well. Cast iron is good.
Aluminum/zinc alloys, start turning back into the ores they were created
from as soon as they are cast. Corrosion is a 4 letter word in my book.
Fixed many kehin and mikuni carbs after they sit with gas in them. Mucho
junk in my world.
Jim Hupy
Salem, Oregon

On Thu, Sep 17, 2020, 6:28 PM dave silva via Gmclist <
gmclist@list.gmcnet.org> wrote:

Seems like most of the generator talk on this and other GMC forums is
'what to replace it with'

I became pretty enamored with the Onan CCK that came with my Revcon.  The
coach has not moved in a long time  but every couple years a hurricane
threatens us and i get the Onan running and it runs FOR DAYS. Then i
forget about it for another couple years.

My recently acquired Birch needed a generator.  I found an Onan Emerald 1
that will just fit with minor mods and should still use the power drawer
rails.

The guys on Smokstack.com understand these things at a very deep level.
THrough them i've had no trouble keeping my old CCK running and getting my
head around the Emerald.

From what i understand, the Power Drawer is not unique. Onan made a whole
bunch of them with a different carb configuration.

Of course there are quieter more fuel efficient gensets but they ain't
cheap and it seems like with a little patience the Original can be made ot
work
pretty well.

Just curious if there other fans of the green anchor.

--
Dave & Ellen Silva

1972 Revcon Olds 455, toro drive train. All Stock


GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Properly maintained, they will outlast their owners and their coaches. I would not get rid of one that was working well. Cast iron is good. Aluminum/zinc alloys, start turning back into the ores they were created from as soon as they are cast. Corrosion is a 4 letter word in my book. Fixed many kehin and mikuni carbs after they sit with gas in them. Mucho junk in my world. Jim Hupy Salem, Oregon On Thu, Sep 17, 2020, 6:28 PM dave silva via Gmclist < gmclist@list.gmcnet.org> wrote: > Seems like most of the generator talk on this and other GMC forums is > 'what to replace it with' > > I became pretty enamored with the Onan CCK that came with my Revcon. The > coach has not moved in a long time but every couple years a hurricane > threatens us and i get the Onan running and it runs FOR DAYS. Then i > forget about it for another couple years. > > My recently acquired Birch needed a generator. I found an Onan Emerald 1 > that will just fit with minor mods and should still use the power drawer > rails. > > The guys on Smokstack.com understand these things at a very deep level. > THrough them i've had no trouble keeping my old CCK running and getting my > head around the Emerald. > > From what i understand, the Power Drawer is not unique. Onan made a whole > bunch of them with a different carb configuration. > > Of course there are quieter more fuel efficient gensets but they ain't > cheap and it seems like with a little patience the Original can be made ot > work > pretty well. > > Just curious if there other fans of the green anchor. > > > > -- > Dave & Ellen Silva > > 1972 Revcon Olds 455, toro drive train. All Stock > > > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org >
MC
Matt Colie
Fri, Sep 18, 2020 1:52 AM

Well, I have a BF (4.0) in my 73-23 that is just about DC3 reliable.  It gets almost 1/3 of the attention it deserves and I know it would start and
run right now if I push the inside button.

Matt

Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit

Well, I have a BF (4.0) in my 73-23 that is just about DC3 reliable. It gets almost 1/3 of the attention it deserves and I know it would start and run right now if I push the inside button. Matt -- Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms SE Michigan - Near DTW - Twixt A2 and Detroit
JH
James Hupy
Fri, Sep 18, 2020 2:08 AM

My 6K Onan has sat since early March without running. I went into the coach
yesterday for an all systems check, and hit the start button on the ONAN.
3ea 10 second bursts on the starter, and she fired up and settled right
down to her governed speed. 15 seconds later, the automatic transfer switch
changed from shore power to generator power, and I turned on the roof air.
Not a burp, or a stumble. Always does that, no issues. It has the
electronic ignition that is crank triggered by a magnet mounted on the
flywheel. Gary Bovee's kit. Works swell. No ignition points to foul. All
systems checked out. She is ready to roll. All we need now is to get rid of
Covid 19, and the wildfires and accompanied smoke.
Jim Hupy
Salem, Oregon

On Thu, Sep 17, 2020, 6:53 PM Matt Colie via Gmclist <
gmclist@list.gmcnet.org> wrote:

Well, I have a BF (4.0) in my 73-23 that is just about DC3 reliable.  It
gets almost 1/3 of the attention it deserves and I know it would start and
run right now if I push the inside button.

Matt

Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit


GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

My 6K Onan has sat since early March without running. I went into the coach yesterday for an all systems check, and hit the start button on the ONAN. 3ea 10 second bursts on the starter, and she fired up and settled right down to her governed speed. 15 seconds later, the automatic transfer switch changed from shore power to generator power, and I turned on the roof air. Not a burp, or a stumble. Always does that, no issues. It has the electronic ignition that is crank triggered by a magnet mounted on the flywheel. Gary Bovee's kit. Works swell. No ignition points to foul. All systems checked out. She is ready to roll. All we need now is to get rid of Covid 19, and the wildfires and accompanied smoke. Jim Hupy Salem, Oregon On Thu, Sep 17, 2020, 6:53 PM Matt Colie via Gmclist < gmclist@list.gmcnet.org> wrote: > Well, I have a BF (4.0) in my 73-23 that is just about DC3 reliable. It > gets almost 1/3 of the attention it deserves and I know it would start and > run right now if I push the inside button. > > Matt > -- > Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, > GMCES > Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum > Brakes with Applied Control Arms > SE Michigan - Near DTW - Twixt A2 and Detroit > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org >
JM
Jim Miller
Fri, Sep 18, 2020 12:35 PM

hertfordnc wrote on Thu, 17 September 2020 21:27

Just curious if there other fans of the green anchor.

Yes, count me as a fan of the Onan. I have them in my two coaches and love them. Add to that the many Onans that I have repaired at GMC work rallies
at my family's compound. Unless they have a rod hanging out the side (which I have never seen) then I can make any of them run. The design is perfect
for our coaches from the standpoint of being 1800 RPM, the cooling system which is intended for operation in the closed compartment and also the
simplicity of the generator section and its excitation circuit. What could be easier than a bridge rectifier, a voltage clamp and a PT/CT
transformer?

There are, of course, improvements that can be made to the ignition system which will help a lot and the original control boards are sketchy after 40
years of exposure to the elements. I have developed replacement choke mechanisms, electronic ignitions (not the Bovee kit), electronic voltage
regulation and also replacement field assemblies which are the common failure items.

I marvel at the negative attitude taken by some GMC owners - especially those on the fakebook group - toward the Onan. The troubleshooting process is
straightforward and logical however many get discouraged when they post about a problem and are rewarded with a cacophony of scattershot replies
ranging from "get rid of it" to any number of other "replace this, replace that" approaches of blindly trying to throw things at the wall and see what
sticks.

--
Jim Miller
1977 Eleganza II
1977 Royale
Hamilton, OH

hertfordnc wrote on Thu, 17 September 2020 21:27 > Just curious if there other fans of the green anchor. Yes, count me as a fan of the Onan. I have them in my two coaches and love them. Add to that the many Onans that I have repaired at GMC work rallies at my family's compound. Unless they have a rod hanging out the side (which I have never seen) then I can make any of them run. The design is perfect for our coaches from the standpoint of being 1800 RPM, the cooling system which is intended for operation in the closed compartment and also the simplicity of the generator section and its excitation circuit. What could be easier than a bridge rectifier, a voltage clamp and a PT/CT transformer? There are, of course, improvements that can be made to the ignition system which will help a lot and the original control boards are sketchy after 40 years of exposure to the elements. I have developed replacement choke mechanisms, electronic ignitions (not the Bovee kit), electronic voltage regulation and also replacement field assemblies which are the common failure items. I marvel at the negative attitude taken by some GMC owners - especially those on the fakebook group - toward the Onan. The troubleshooting process is straightforward and logical however many get discouraged when they post about a problem and are rewarded with a cacophony of scattershot replies ranging from "get rid of it" to any number of other "replace this, replace that" approaches of blindly trying to throw things at the wall and see what sticks. -- Jim Miller 1977 Eleganza II 1977 Royale Hamilton, OH
DK
Dave King
Fri, Sep 18, 2020 12:48 PM

This is specifically directed to Mr. ONAN Jim Miller. I find it truly amazing that Jim has developed a process
to rewind ONAN fields with copper wire. What is more amazing is that he will actually do this for
other people. Some GMC folks are truly special. My 1976 SOB may have come with an ONAN but when I
got the MH about 1990 the TROLL was gone, replaced with something else as a makeshift install.
Because of the info available on this forum and by extension from articles people on here have
created, I wish I had an ONAN every time my ***** won't start.

THANK YOU JIM M. and others on this forum !!!

DAVE KING
lurker, wannabe
Toronto, Ontario, Canada

This is specifically directed to Mr. ONAN Jim Miller. I find it truly amazing that Jim has developed a process to rewind ONAN fields with copper wire. What is more amazing is that he will actually do this for other people. Some GMC folks are truly special. My 1976 SOB may have come with an ONAN but when I got the MH about 1990 the TROLL was gone, replaced with something else as a makeshift install. Because of the info available on this forum and by extension from articles people on here have created, I wish I had an ONAN every time my ***** won't start. THANK YOU JIM M. and others on this forum !!! -- DAVE KING lurker, wannabe Toronto, Ontario, Canada
BW
Bill Wevers
Fri, Sep 18, 2020 4:17 PM

My 6KW Onan starts reliably. It has Bovee's ignition. It usually starts after a few seconds of cranking. The only problem is when the air temperature
gets over 115ºF it vapor locks with the alcohol gas. Maybe if I pull the drawer out it will cool better.

Bill Wevers  GMC49ers, GMC Western States
1975 Glenbrook - Manny Powerdrive, OneTon
455 F Block, G heads
San Jose

My 6KW Onan starts reliably. It has Bovee's ignition. It usually starts after a few seconds of cranking. The only problem is when the air temperature gets over 115ºF it vapor locks with the alcohol gas. Maybe if I pull the drawer out it will cool better. -- Bill Wevers GMC49ers, GMC Western States 1975 Glenbrook - Manny Powerdrive, OneTon 455 F Block, G heads San Jose
RJ
Robert J. Gogan
Fri, Sep 18, 2020 5:34 PM

At the last GMC international rally that I attended in Iowa, I polled the attendees at a generator lecture for the number of hours that they had on
their Onan's.  I hold the record for that poll at over 2000 hrs.  However, those hours certainly did not come painlessly.
I have made just about every imaginable repair possible and here are some highlights that others may have not seen:

  1. Some models of the facet electric fuel pump came without a grommet for the 12v wire power supply.  When running the generator, I would have
    intermittent failures especially when the generator would run rough and vibrate.  Eventually, the fuse would blow randomly for no diagnosable reason.
    One night I was looking at the fuel pump in the dark and noted arcing between the 12v supply and the case of the fuel pump.  The wire's insulation has
    worn through and the wire was grounding to the case causing the intermittent engine failure and eventually the fuse blowing.  Prior to this, it had
    actually burned out some printed circuit tracings on the control board when I tried to insert an oversized fuse.  I replaced the pump with a properly
    grommeted one and also the circuit board was upgraded to a new design totally covered with some type of silicon insulation. More happy times.

  2. More recently, I felt that irregular running and random stopping of the engine was related to the mechanical points.  I fooled around with every
    conceivable gap and filing the points without help. Finally I bought the point set from Applied GMC that allows adjustment when the engine is running.
    Still, I could not get a smooth operation no matter the gap or timing.  Finally found that the wire exiting the point box through a narrow slit in the
    box that was without a grommet, had its insulation worn through.  Replaced that wire and had excellent results.  I had ordered the electronic ignition
    upgrade but never bothered to install it after that problem was fixed. More happy times.

  3. The most challenging problem was the Walbro LMB 185 carb.  Experienced more problems with erratic operation that did not improve with a carb
    rebuild kit.  Still suspecting it was a carb problem, I sprayed light oil on the carb and intake manifold gasket and had a sudden change in the RPMs.
    Checked the intake manifold gasket and found it was not leaking.  Finally found that the shaft of the butterfly throttle had worn out the bushing in
    the housing.  I was lucky enough on Ebay to find an unused carb that had been sitting on an inventory shelf for 40yrs.  It was a  LMB 181 and
    externally was identical to the original Onan carb. I purchased and installed it, and despite all my previous problems, I am in love with this
    generator again.  The operation is unbelievable smooth and power has been restored.  Hardly any RPM change when both roof A/Cs kick in. This is even
    with the electric water heater in operation. Does anyone rebuild or rebush the throttle shaft?

This outlines some of my more unusual problems that can be easily averted with inspection of the wiring and regular lubrication of the throttle shaft
bushing.  If you would like to hear about the other 10 more common problems, let me know.
Bob Gogan

At the last GMC international rally that I attended in Iowa, I polled the attendees at a generator lecture for the number of hours that they had on their Onan's. I hold the record for that poll at over 2000 hrs. However, those hours certainly did not come painlessly. I have made just about every imaginable repair possible and here are some highlights that others may have not seen: 1) Some models of the facet electric fuel pump came without a grommet for the 12v wire power supply. When running the generator, I would have intermittent failures especially when the generator would run rough and vibrate. Eventually, the fuse would blow randomly for no diagnosable reason. One night I was looking at the fuel pump in the dark and noted arcing between the 12v supply and the case of the fuel pump. The wire's insulation has worn through and the wire was grounding to the case causing the intermittent engine failure and eventually the fuse blowing. Prior to this, it had actually burned out some printed circuit tracings on the control board when I tried to insert an oversized fuse. I replaced the pump with a properly grommeted one and also the circuit board was upgraded to a new design totally covered with some type of silicon insulation. More happy times. 2) More recently, I felt that irregular running and random stopping of the engine was related to the mechanical points. I fooled around with every conceivable gap and filing the points without help. Finally I bought the point set from Applied GMC that allows adjustment when the engine is running. Still, I could not get a smooth operation no matter the gap or timing. Finally found that the wire exiting the point box through a narrow slit in the box that was without a grommet, had its insulation worn through. Replaced that wire and had excellent results. I had ordered the electronic ignition upgrade but never bothered to install it after that problem was fixed. More happy times. 3) The most challenging problem was the Walbro LMB 185 carb. Experienced more problems with erratic operation that did not improve with a carb rebuild kit. Still suspecting it was a carb problem, I sprayed light oil on the carb and intake manifold gasket and had a sudden change in the RPMs. Checked the intake manifold gasket and found it was not leaking. Finally found that the shaft of the butterfly throttle had worn out the bushing in the housing. I was lucky enough on Ebay to find an unused carb that had been sitting on an inventory shelf for 40yrs. It was a LMB 181 and externally was identical to the original Onan carb. I purchased and installed it, and despite all my previous problems, I am in love with this generator again. The operation is unbelievable smooth and power has been restored. Hardly any RPM change when both roof A/Cs kick in. This is even with the electric water heater in operation. Does anyone rebuild or rebush the throttle shaft? This outlines some of my more unusual problems that can be easily averted with inspection of the wiring and regular lubrication of the throttle shaft bushing. If you would like to hear about the other 10 more common problems, let me know. Bob Gogan
MS
Mark Sawyer
Fri, Sep 18, 2020 8:55 PM

Another fan of the Onan here...  She does what she needs to do with a minimum of fuss.

As for the carb, I think up to a year or 2 ago, you could send it back to Walbro for a rebuild...  Though I believe the may have discontinued that
service.

I like my Onan even more with the Bovee ignition and dual fuel kit...  I can't think of the gentlemen's name who worked with US Carb on the kit a few
years back, but I picked mine up shortly after and I love it.

Generally run it on gas when going down the road for convenience sake... (Easier to fill the gas tank than the propane) but when I'm running it
stationary, propane is the way to go...

Mark S.  '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX

Another fan of the Onan here... She does what she needs to do with a minimum of fuss. As for the carb, I think up to a year or 2 ago, you could send it back to Walbro for a rebuild... Though I believe the may have discontinued that service. I like my Onan even more with the Bovee ignition and dual fuel kit... I can't think of the gentlemen's name who worked with US Carb on the kit a few years back, but I picked mine up shortly after and I love it. Generally run it on gas when going down the road for convenience sake... (Easier to fill the gas tank than the propane) but when I'm running it stationary, propane is the way to go... -- Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
JH
James Hupy
Fri, Sep 18, 2020 9:04 PM

Jerry Work is the gentleman's name.
Jim Hupy
Salem, Oregon

On Fri, Sep 18, 2020, 1:56 PM Mark Sawyer via Gmclist <
gmclist@list.gmcnet.org> wrote:

Another fan of the Onan here...  She does what she needs to do with a
minimum of fuss.

As for the carb, I think up to a year or 2 ago, you could send it back to
Walbro for a rebuild...  Though I believe the may have discontinued that
service.

I like my Onan even more with the Bovee ignition and dual fuel kit...  I
can't think of the gentlemen's name who worked with US Carb on the kit a few
years back, but I picked mine up shortly after and I love it.

Generally run it on gas when going down the road for convenience sake...
(Easier to fill the gas tank than the propane) but when I'm running it
stationary, propane is the way to go...

Mark S.  '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX


GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Jerry Work is the gentleman's name. Jim Hupy Salem, Oregon On Fri, Sep 18, 2020, 1:56 PM Mark Sawyer via Gmclist < gmclist@list.gmcnet.org> wrote: > Another fan of the Onan here... She does what she needs to do with a > minimum of fuss. > > As for the carb, I think up to a year or 2 ago, you could send it back to > Walbro for a rebuild... Though I believe the may have discontinued that > service. > > I like my Onan even more with the Bovee ignition and dual fuel kit... I > can't think of the gentlemen's name who worked with US Carb on the kit a few > years back, but I picked mine up shortly after and I love it. > > Generally run it on gas when going down the road for convenience sake... > (Easier to fill the gas tank than the propane) but when I'm running it > stationary, propane is the way to go... > -- > Mark S. '73 Painted Desert, > Manny 1 Ton Front End, > Howell Injection, > Leigh Harrison 4bag and Rear Brakes, > Fort Worth, TX > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org >