Noisy Onan

[Deb]

Got the Onan running, but not well I think. Sat for 4 days after getting it back, took about 15 seconds to start (sounded like wasn't getting fuel;
fine on re-start). Since I have never had it running, and haven't heard another, I can't be certain, but I don't think it should sound like
this....https://www.screencast.com/t/3dRknmXzB

Oil, filter, etc all good, new fuel filter.

Of course louder than is coming up here, like a metal fan striking the housing, but more intense. Any ideas about what I'm looking at here before I
take the next step? Or you tell me what that should be

Thanks for your insight... I have none naturally. Deb
--
Deb McWade
Logan Lake, BC, CAN
"Li'l Sister"
'77 Kingsley, 403, EBL EFI;
TZE167V101404
It's Bigger on the Inside!

 

[Jim Hupy]

The choke is kinda touchy when starting from cold. Usually, if you have a
problem on cold start, and you adjust for that, then when the unit is
warmed up, the choke is too rich. Touchy adjustment. Sometimes the ground
wire on the choke is rusty and corroded. A cleanup helps. Worth a try.
Jim Hupy

> Got the Onan running, but not well I think. Sat for 4 days after getting
> it back, took about 15 seconds to start (sounded like wasn't getting fuel;
> fine on re-start). Since I have never had it running, and haven't heard
> another, I can't be certain, but I don't think it should sound like
> this....https://www.screencast.com/t/3dRknmXzB
>
> Oil, filter, etc all good, new fuel filter.
>
> Of course louder than is coming up here, like a metal fan striking the
> housing, but more intense. Any ideas about what I'm looking at here before
> I
> take the next step? Or you tell me what that should be
>
> Thanks for your insight... I have none naturally. Deb
> --
> 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 Hupy]

Rattle when running could be the engine mount cushions. When they fail, the
starter bracket rattles against the frame. Not too difficult to change.
Applied has them in stock.

> The choke is kinda touchy when starting from cold. Usually, if you have a
> problem on cold start, and you adjust for that, then when the unit is
> warmed up, the choke is too rich. Touchy adjustment. Sometimes the ground
> wire on the choke is rusty and corroded. A cleanup helps. Worth a try.
> Jim Hupy
>

>
>> Got the Onan running, but not well I think. Sat for 4 days after getting
>> it back, took about 15 seconds to start (sounded like wasn't getting fuel;
>> fine on re-start). Since I have never had it running, and haven't heard
>> another, I can't be certain, but I don't think it should sound like
>> this....https://www.screencast.com/t/3dRknmXzB
>>
>> Oil, filter, etc all good, new fuel filter.
>>
>> Of course louder than is coming up here, like a metal fan striking the
>> housing, but more intense. Any ideas about what I'm looking at here before
>> I
>> take the next step? Or you tell me what that should be
>>
>> Thanks for your insight... I have none naturally. Deb
>> --
>> 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
>>
>

 

[Deb]

> Rattle when running could be the engine mount cushions. When they fail, the
> starter bracket rattles against the frame. Not too difficult to change.
> Applied has them in stock.

Thanks James. Sounds more like a rubbing sound than a rattle, but I will take a look at the mounts and also check the starter bracket. Hopefully
something simple like that. But I don't hold my breath on anything anymore
--
Deb McWade
Logan Lake, BC, CAN
"Li'l Sister"
'77 Kingsley, 403, EBL EFI;
TZE167V101404
It's Bigger on the Inside!

 

[SteveW]

On mine - the oil fill tube cap got a little loose and rattled...

I don't remember how I tightened it back up - might have been a rivet - but I know it was the source of rattling because when I pressed it into place
- the rattling stopped.

Good Luck !

Steve W
1973 23' Yellow
Southern California

 

[RJW]

> Got the Onan running, but not well I think. Sat for 4 days after getting it back, took about 15 seconds to start (sounded like wasn't getting
> fuel; fine on re-start). Since I have never had it running, and haven't heard another, I can't be certain, but I don't think it should sound like
> this....https://www.screencast.com/t/3dRknmXzB
>
> Oil, filter, etc all good, new fuel filter.
>
> Of course louder than is coming up here, like a metal fan striking the housing, but more intense. Any ideas about what I'm looking at here before
> I take the next step? Or you tell me what that should be
>
> Thanks for your insight... I have none naturally. Deb

My Onan developed a sound just like that on my last trip. Turned out the flywheel was loose and rubbing against the front of the Onan. Made a sound
just like your audio file. All I had to do was tightened the bolt back to spec and the rattle went away.
--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Manny Tranny etc.

 

[Will Albers]

Running on half the engine? Pull one plug wire, see if it dies vs no change
at all.

> > Rattle when running could be the engine mount cushions. When they fail,
> the
> > starter bracket rattles against the frame. Not too difficult to change.
> > Applied has them in stock.
>
>
> Thanks James. Sounds more like a rubbing sound than a rattle, but I will
> take a look at the mounts and also check the starter bracket. Hopefully
> something simple like that. But I don't hold my breath on anything
> anymore
> --
> 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
>

 

[jerry work]

The choke on the Onan is only pulled on while the starter is turning over. =
Once the starter stops turning the choke is not held closed electrically. =
I found that out while designing the kit that allows the Onan to run off e=
ither gasoline or propane at the flip of one DPDT toggle switch. I used th=
at same choke circuit to open the propane bypass valve to allow propane to =
flow around the demand regulator while the starter was engaged. The other =
side of the DPDT toggle switch either powered the fuel pump (while on gasol=
ine) or the propane shut off valve (while on propane). It is very easy to =
flood the Onan running on gasoline if the spark control is still via the ol=
d points. In that case the weak spark makes it hard to start keeping the s=
tarter motor engaged for longer than it was designed to be resulting in too=
much gas and wet plugs that do not fire well. Change out the spark contro=
l to a pertronics kit like the one developed by Gary Bovee and most Onan ru=
nning/starting issues will be a thing of the past, especially if you run it=
off propane. It just is not worth the hassle to try to make that old thin=
g run off gasoline unless you replace every rubber part that touched the et=
hanol laced junk now sold as gasoline. That includes the gaskets and o rin=
gs in the original fuel pump and carb, the line coming to the fuel pump, an=
d including the tiny o ring in the carb. Then make sure you have cleaned t=
he strainer in the carb and fiddle for way too long trying to get it adjust=
ed to where it will run properly at idle and under load. With propane it i=
s set, forget and enjoy unless something physically breaks inside the barba=
rian. Jerry Jerry Work The Dovetail Joint Fine furniture designe=
d and hand crafted in the 1907 former Masonic Temple building in historic K=
erby, OR glwork http://jerrywork.com =
Message: 5 Date: Thu, 7 Jun 2018 10:41:16 -0700 Fr=
om: James Hupy To: gmclist Subje=
ct: Re: [GMCnet] Noisy Onan Message-ID: =09 Content-Type: text/plain; char=
set "UTF-8" The choke is kinda touchy when starting from cold. Usual=
ly, if you have a problem on cold start, and you adjust for that, then wh=
en the unit is warmed up, the choke is too rich. Touchy adjustment. Somet=
imes the ground wire on the choke is rusty and corroded. A cleanup helps.=
Worth a try. Jim Hupy On Thu, Jun 7, 2018, 10:34 AM Deb McWade wrote: > Got the Onan running, but not well I think. Sa=
t for 4 days after getting > it back, took about 15 seconds to start (sou=
nded like wasn't getting fuel; > fine on re-start). Since I have never h=
ad it running, and haven't heard > another, I can't be certain, but I don=
't think it should sound like > this....https://www.screencast.com/t/3dRk=
nmXzB > > Oil, filter, etc all good, new fuel filter. > > Of cour=
se louder than is coming up here, like a metal fan striking the > housing=
, but more intense. Any ideas about what I'm looking at here before > I=
> take the next step? Or you tell me what that should be > > Th=
anks for your insight... I have none naturally. Deb > -- > Deb McWade=
> Logan Lake, BC, CAN > "Li'l Sister" > '77 Kingsley, 403, EBL EFI;=
> TZE167V101404 > It's Bigger on the Inside! > > > ___________=
____________________________________ > GMCnet mailing list > Unsubscrib=
e or Change List Options: > http://list.gmcnet.org/mailman/listinfo/gmcli=
st_list.gmcnet.org

 

[Ken H.]

Will,

Pulling either plug wire will ALWAYS kill an Onan because it uses a "lost
spark" ignition system. Maybe you've noticed that there is no distributor
on its engine -- merely two high voltage wires coming out of the ignition
coil. Those wires connect to each end of the coil's secondary winding.
Since the cylinders are opposed, one is on the exhaust stroke when the
other is on the compression stroke. The impedance (call it resistance if
you like) of the mixture in the exhaust cylinder is very low, so the
ignition voltage "interprets" that as a ground connection and generates
only a low voltage drop there. Conversely, the other cylinder's highly
compressed mixture presents a high impedance, across which the ignition
coil generates a high enough voltage to cause an ignition arc.
Disconnecting either plug wire disrupts that careful balance and the engine
cannot run. Now, if you connect the disconnected wire to ground, the other
cylinder CAN still fire and the engine run POORLY. But when you pull that
wire off, the engine will die immediately; it may or may not restart on
that single cylinder.

To check for spark at a removed spark plug, or a pulled plug wire, it's
always necessary to securely ground the other plug wire. Even then, the
Onan's spark will be very faint. One more good reason to install the
Pertronix upgrade pioneered by Lawrence Gaskins.

Ken H.

> Running on half the engine? Pull one plug wire, see if it dies vs no change
> at all.
>

>

> > > Rattle when running could be the engine mount cushions. When they fail,
> > the
> > > starter bracket rattles against the frame. Not too difficult to change.
> > > Applied has them in stock.
> >
> >
> > Thanks James. Sounds more like a rubbing sound than a rattle, but I will
> > take a look at the mounts and also check the starter bracket. Hopefully
> > something simple like that. But I don't hold my breath on anything
> > anymore
> > --
> > 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
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

 

[Deb]

Thanks Jerry - I do have the Bovee ignition system. Thought I would try to get it running before I went to the trouble of installing it in case she
was totally beyond repair. But that is on my list of things to try to do in the next 5 days before I head out.

And I am very interested in converting it to propane! Get through this season (or at least this one trip) and then I'll be in touch for some
information! Cheers. Deb
--
Deb McWade
Logan Lake, BC, CAN
"Li'l Sister"
'77 Kingsley, 403, EBL EFI;
TZE167V101404
It's Bigger on the Inside!

 

[Deb]

> > Got the Onan running, but not well I think. Sat for 4 days after getting it back, took about 15 seconds to start (sounded like wasn't getting
> > fuel; fine on re-start). Since I have never had it running, and haven't heard another, I can't be certain, but I don't think it should sound like
> > this....https://www.screencast.com/t/3dRknmXzB
> >
> > Oil, filter, etc all good, new fuel filter.
> >
> > Of course louder than is coming up here, like a metal fan striking the housing, but more intense. Any ideas about what I'm looking at here
> > before I take the next step? Or you tell me what that should be
> >
> > Thanks for your insight... I have none naturally. Deb
>
> My Onan developed a sound just like that on my last trip. Turned out the flywheel was loose and rubbing against the front of the Onan. Made a
> sound just like your audio file. All I had to do was tightened the bolt back to spec and the rattle went away.

Sounds like a definite possibility! Wouldn't it be nice if it turns out to be that simple?! What is the spec torque on the nut BTW? She's parked
tomorrow (have to head to work for the last day before I dedicate myself to getting everything set to go). But the weekend, Tues & Wed are GMC days!
Will be pulling the drawer and going over it - if we have time, maybe even put Gary's pertronix ignition in!!
--
Deb McWade
Logan Lake, BC, CAN
"Li'l Sister"
'77 Kingsley, 403, EBL EFI;
TZE167V101404
It's Bigger on the Inside!

 

[jack christensen1]

In addition to Gary's Pertronix ignition mod you might want to consider Jerry Work's propane conversion. My Onan starts and runs so much better with
it. You buy it as a kit from US Carburetion.
--
Jack Christensen - K6ROW,
'76 Glenbrook/Clasco - "The Silver Bullet",
Sebastopol, CA

 

[bdub1]

http://gmcws.org/blog/onan-on-propane-by-george-beckman/

> Thanks Jerry - I do have the Bovee ignition system. Thought I would try
> to get it running before I went to the trouble of installing it in case she
> was totally beyond repair. But that is on my list of things to try to do
> in the next 5 days before I head out.
>
> And I am very interested in converting it to propane! Get through this
> season (or at least this one trip) and then I'll be in touch for some
> information! Cheers. Deb

 

[Deb]

> http://gmcws.org/blog/onan-on-propane-by-george-beckman/
>
>

>
> > Thanks Jerry - I do have the Bovee ignition system. Thought I would try
> > to get it running before I went to the trouble of installing it in case she
> > was totally beyond repair. But that is on my list of things to try to do
> > in the next 5 days before I head out.
> >
> > And I am very interested in converting it to propane! Get through this
> > season (or at least this one trip) and then I'll be in touch for some
> > information! Cheers. Deb
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
Deb McWade
Logan Lake, BC, CAN
"Li'l Sister"
'77 Kingsley, 403, EBL EFI;
TZE167V101404
It's Bigger on the Inside!

 

[Deb]

> In addition to Gary's Pertronix ignition mod you might want to consider Jerry Work's propane conversion. My Onan starts and runs so much better
> with it. You buy it as a kit from US Carburetion.

Jerry mentioned that - also on my list. Hoping the noise is just the flywheel and an adjustment will help solve that. I'll know better Saturday...
Thanks for the link to the kit!
--
Deb McWade
Logan Lake, BC, CAN
"Li'l Sister"
'77 Kingsley, 403, EBL EFI;
TZE167V101404
It's Bigger on the Inside!

 

[RJW]

> > > Got the Onan running, but not well I think. Sat for 4 days after getting it back, took about 15 seconds to start (sounded like wasn't
> > > getting fuel; fine on re-start). Since I have never had it running, and haven't heard another, I can't be certain, but I don't think it should
> > > sound like this....https://www.screencast.com/t/3dRknmXzB
> > >
> > > Oil, filter, etc all good, new fuel filter.
> > >
> > > Of course louder than is coming up here, like a metal fan striking the housing, but more intense. Any ideas about what I'm looking at
> > > here before I take the next step? Or you tell me what that should be
> > >
> > > Thanks for your insight... I have none naturally. Deb
> >
> > My Onan developed a sound just like that on my last trip. Turned out the flywheel was loose and rubbing against the front of the Onan. Made a
> > sound just like your audio file. All I had to do was tightened the bolt back to spec and the rattle went away.
>
>
>
> Sounds like a definite possibility! Wouldn't it be nice if it turns out to be that simple?! What is the spec torque on the nut BTW? She's parked
> tomorrow (have to head to work for the last day before I dedicate myself to getting everything set to go). But the weekend, Tues & Wed are GMC
> days! Will be pulling the drawer and going over it - if we have time, maybe even put Gary's pertronix ignition in!!


According to my Onan "Major Service Manual for NH Power Drawer, 6KW Electric Power Plant for Recreational Vehicles" booklet, the flywheel mounting
screw torque is Min of 35 and Max of 40 foot pounds. Too much torque and you run the risk of cracking it.
--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Manny Tranny etc.