Home » Public Forums » GMCnet » [GMCnet] Onan bumping/knocking sound?
| [GMCnet] Onan bumping/knocking sound? [message #240240] |
Sun, 16 February 2014 13:44  |
John Olson
Messages: 96
Registered: August 2013
Karma: 0
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Member |
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Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan Wash
BLM in Quartzite.
Today is running seemingly fine, but from inside the coach, I hear an
intermittent sound I can best describe as
*similar to a small shoe tumbling in a dryer. *
Irregular faint thump sound. Normal sound for 15-25 seconds, faint and
irregular thump for 5-10 seconds. Repeat.
NOT engine lope sound. Engine hum is consistent...no loping.
Onan links and info has been collected. Have read manuals, troubleshooting
guides.
The community guides to onan are great resources, but it seems to run fine
according to troubleshooter items (starting, power output, pressure, etc.).
Checked oil. Needs changing, but is full. Will change asap.
Air filter has some dust but is not caked. Will clean/replace.
Plugs are rusted in wrench collar area but seem to work ok. Will replace
asap.
John Olson
76 Edgemont (the one with the minor thumping Onan)
Chicago, IL (currently in Scaddan Wash BLM in Quartzite)
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76 Edgemonte
Fulltime traveler
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240243 is a reply to message #240240] |
Sun, 16 February 2014 16:13  |
 |
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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John,
Check the mounts, they collapse over time and the unit could be bumping into something in its compartment.
Regards,
Rob M.
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
PS - Add an "e" to the end of Edgemont. ;-)
-----Original Message-----
From: John Olson
Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan Wash BLM in Quartzite.
Today is running seemingly fine, but from inside the coach, I hear an intermittent sound I can best describe as *similar to a small
shoe tumbling in a dryer. * Irregular faint thump sound. Normal sound for 15-25 seconds, faint and irregular thump for 5-10 seconds.
Repeat.
NOT engine lope sound. Engine hum is consistent...no loping.
Onan links and info has been collected. Have read manuals, troubleshooting guides.
The community guides to onan are great resources, but it seems to run fine according to troubleshooter items (starting, power
output, pressure, etc.).
Checked oil. Needs changing, but is full. Will change asap.
Air filter has some dust but is not caked. Will clean/replace.
Plugs are rusted in wrench collar area but seem to work ok. Will replace asap.
John Olson
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Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240248 is a reply to message #240243] |
Sun, 16 February 2014 17:12 |
John Olson
Messages: 96
Registered: August 2013
Karma: 0
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Thanks Rob, I'll check those. I do remember the rubber mounts looking sad.
Not to mention the death rattle it causes to the rig on shut down...SOME
significant rattle was expected but this is like standing in a paint shaker
for 5-10 seconds.
John Olson
76 Edgemont (I'll add the E only when driving in the UK :-) )
On Sun, Feb 16, 2014 at 3:13 PM, Robert Mueller <robmueller@iinet.net.au>wrote:
> John,
>
> Check the mounts, they collapse over time and the unit could be bumping
> into something in its compartment.
>
> Regards,
> Rob M.
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
> PS - Add an "e" to the end of Edgemont. ;-)
>
> -----Original Message-----
> From: John Olson
>
> Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan Wash
> BLM in Quartzite.
>
> Today is running seemingly fine, but from inside the coach, I hear an
> intermittent sound I can best describe as *similar to a small
> shoe tumbling in a dryer. * Irregular faint thump sound. Normal sound for
> 15-25 seconds, faint and irregular thump for 5-10 seconds.
> Repeat.
>
> NOT engine lope sound. Engine hum is consistent...no loping.
>
> Onan links and info has been collected. Have read manuals, troubleshooting
> guides.
>
> The community guides to onan are great resources, but it seems to run fine
> according to troubleshooter items (starting, power
> output, pressure, etc.).
>
>
> Checked oil. Needs changing, but is full. Will change asap.
>
> Air filter has some dust but is not caked. Will clean/replace.
>
> Plugs are rusted in wrench collar area but seem to work ok. Will replace
> asap.
>
> John Olson
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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John Olson
76 Edgemonte
Fulltime traveler
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240254 is a reply to message #240240] |
Sun, 16 February 2014 18:33 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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First a silly, because I've had it happen on my big sets.... any chance you've got a mouse nest or (expired) rodent too big to fit between the blades bouncing around in the fan?
Reasonable - any chance the motor mounts are dying and under some conditions part of the set - usually the starter housing - is occasionally bumping the drawer?
Quick n dirty way to test - take a crowbar or large screwdriver, fire it up, and then lift and twist and pry and see if you can get it to make the sound. How you move it to do so will clue you as to what's hitting and you can go find it.
--johnny
________________________________
From: John Olson <johnolsondesign@gmail.com>
To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
Sent: Sunday, February 16, 2014 2:44 PM
Subject: [GMCnet] Onan bumping/knocking sound?
Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan Wash
BLM in Quartzite.
Today is running seemingly fine, but from inside the coach, I hear an
intermittent sound I can best describe as
*similar to a small shoe tumbling in a dryer. *
Irregular faint thump sound. Normal sound for 15-25 seconds, faint and
irregular thump for 5-10 seconds. Repeat.
NOT engine lope sound. Engine hum is consistent...no loping.
Onan links and info has been collected. Have read manuals, troubleshooting
guides.
The community guides to onan are great resources, but it seems to run fine
according to troubleshooter items (starting, power output, pressure, etc.).
Checked oil. Needs changing, but is full. Will change asap.
Air filter has some dust but is not caked. Will clean/replace.
Plugs are rusted in wrench collar area but seem to work ok. Will replace
asap.
John Olson
76 Edgemont (the one with the minor thumping Onan)
Chicago, IL (currently in Scaddan Wash BLM in Quartzite)
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Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240255 is a reply to message #240254] |
Sun, 16 February 2014 18:55 |
John Olson
Messages: 96
Registered: August 2013
Karma: 0
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Member |
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Thanks for the tip Johnny. Mouse nest is definitely possible. I'll add that
to the list to check.
We had a birds nest right inside the AC blower motor. Found a dormant
rodent nest on top of the 455. I think this one, like many, sat outside for
a spell a few years ago based on the nest evidence (dormant old looking).
JOhn
On Sun, Feb 16, 2014 at 5:33 PM, Johnny Bridges <jhbridges@ymail.com> wrote:
> First a silly, because I've had it happen on my big sets.... any chance
> you've got a mouse nest or (expired) rodent too big to fit between the
> blades bouncing around in the fan?
> Reasonable - any chance the motor mounts are dying and under some
> conditions part of the set - usually the starter housing - is occasionally
> bumping the drawer?
> Quick n dirty way to test - take a crowbar or large screwdriver, fire it
> up, and then lift and twist and pry and see if you can get it to make the
> sound. How you move it to do so will clue you as to what's hitting and you
> can go find it.
>
> --johnny
>
>
>
> ________________________________
> From: John Olson <johnolsondesign@gmail.com>
> To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
> Sent: Sunday, February 16, 2014 2:44 PM
> Subject: [GMCnet] Onan bumping/knocking sound?
>
>
> Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan Wash
> BLM in Quartzite.
>
> Today is running seemingly fine, but from inside the coach, I hear an
> intermittent sound I can best describe as
> *similar to a small shoe tumbling in a dryer. *
> Irregular faint thump sound. Normal sound for 15-25 seconds, faint and
> irregular thump for 5-10 seconds. Repeat.
>
> NOT engine lope sound. Engine hum is consistent...no loping.
>
>
> Onan links and info has been collected. Have read manuals, troubleshooting
> guides.
>
> The community guides to onan are great resources, but it seems to run fine
> according to troubleshooter items (starting, power output, pressure, etc.).
>
>
> Checked oil. Needs changing, but is full. Will change asap.
>
> Air filter has some dust but is not caked. Will clean/replace.
>
> Plugs are rusted in wrench collar area but seem to work ok. Will replace
> asap.
>
>
>
> John Olson
> 76 Edgemont (the one with the minor thumping Onan)
> Chicago, IL (currently in Scaddan Wash BLM in Quartzite)
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
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John Olson
76 Edgemonte
Fulltime traveler
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240258 is a reply to message #240240] |
Sun, 16 February 2014 19:28 |
John Olson
Messages: 96
Registered: August 2013
Karma: 0
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Member |
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Pics of oil leaking issues and a cracked Electric Choke (I think thats what
it is).
http://www.gmcmhphotos.com/photos/g6541-onan-issues.html
Ideas about how to stop the leaking and fix the broken choke part?
John Olson
76 Edgemont (the one with the messy onan)
Chicago, IL (currently in Qsite AZ)
On Sun, Feb 16, 2014 at 5:55 PM, John Olson <johnolsondesign@gmail.com>wrote:
> Thanks for the tip Johnny. Mouse nest is definitely possible. I'll add
> that to the list to check.
>
> We had a birds nest right inside the AC blower motor. Found a dormant
> rodent nest on top of the 455. I think this one, like many, sat outside for
> a spell a few years ago based on the nest evidence (dormant old looking).
>
> JOhn
>
> On Sun, Feb 16, 2014 at 5:33 PM, Johnny Bridges <jhbridges@ymail.com>wrote:
>
>> First a silly, because I've had it happen on my big sets.... any chance
>> you've got a mouse nest or (expired) rodent too big to fit between the
>> blades bouncing around in the fan?
>> Reasonable - any chance the motor mounts are dying and under some
>> conditions part of the set - usually the starter housing - is occasionally
>> bumping the drawer?
>> Quick n dirty way to test - take a crowbar or large screwdriver, fire it
>> up, and then lift and twist and pry and see if you can get it to make the
>> sound. How you move it to do so will clue you as to what's hitting and you
>> can go find it.
>>
>> --johnny
>>
>>
>>
>> ________________________________
>> From: John Olson <johnolsondesign@gmail.com>
>> To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
>> Sent: Sunday, February 16, 2014 2:44 PM
>> Subject: [GMCnet] Onan bumping/knocking sound?
>>
>>
>> Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan Wash
>> BLM in Quartzite.
>>
>> Today is running seemingly fine, but from inside the coach, I hear an
>> intermittent sound I can best describe as
>> *similar to a small shoe tumbling in a dryer. *
>> Irregular faint thump sound. Normal sound for 15-25 seconds, faint and
>> irregular thump for 5-10 seconds. Repeat.
>>
>> NOT engine lope sound. Engine hum is consistent...no loping.
>>
>>
>> Onan links and info has been collected. Have read manuals, troubleshooting
>> guides.
>>
>> The community guides to onan are great resources, but it seems to run fine
>> according to troubleshooter items (starting, power output, pressure,
>> etc.).
>>
>>
>> Checked oil. Needs changing, but is full. Will change asap.
>>
>> Air filter has some dust but is not caked. Will clean/replace.
>>
>> Plugs are rusted in wrench collar area but seem to work ok. Will replace
>> asap.
>>
>>
>>
>> John Olson
>> 76 Edgemont (the one with the minor thumping Onan)
>> Chicago, IL (currently in Scaddan Wash BLM in Quartzite)
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
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John Olson
76 Edgemonte
Fulltime traveler
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240269 is a reply to message #240240] |
Mon, 17 February 2014 18:18 |
 |
ljdavick
Messages: 3548
Registered: March 2007
Location: Fremont, CA
Karma: -3
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Senior Member |
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Could the thump be coming from somewhere else -maybe the water heater?
Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, CA
> On Feb 16, 2014, at 11:44 AM, John Olson <johnolsondesign@gmail.com> wrote:
>
> Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan Wash
> BLM in Quartzite.
>
> Today is running seemingly fine, but from inside the coach, I hear an
> intermittent sound I can best describe as
> *similar to a small shoe tumbling in a dryer. *
> Irregular faint thump sound. Normal sound for 15-25 seconds, faint and
> irregular thump for 5-10 seconds. Repeat.
>
> NOT engine lope sound. Engine hum is consistent...no loping.
>
>
> Onan links and info has been collected. Have read manuals, troubleshooting
> guides.
>
> The community guides to onan are great resources, but it seems to run fine
> according to troubleshooter items (starting, power output, pressure, etc.).
>
>
> Checked oil. Needs changing, but is full. Will change asap.
>
> Air filter has some dust but is not caked. Will clean/replace.
>
> Plugs are rusted in wrench collar area but seem to work ok. Will replace
> asap.
>
>
>
> John Olson
> 76 Edgemont (the one with the minor thumping Onan)
> Chicago, IL (currently in Scaddan Wash BLM in Quartzite)
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240273 is a reply to message #240254] |
Sun, 16 February 2014 21:45 |
|
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Senior Member |
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Johnny,
Outside of flywheel / fan
http://www.gmcmhphotos.com/photos/pitiful-gmc/p51682-bad-condition.html
I couldn't find a photo of the other side of the fan on the photo site. Basically it looks the same but air goes in a large central
hole and out through the finned OD.
John reported that the sound he's hearing is when the Onan is running I reckon centrifugal force would keep a rodent pressed up
against the fan blades when the Onan is running.
Regards,
Rob M.
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
-----Original Message-----
From: Johnny Bridges
First a silly, because I've had it happen on my big sets.... any chance you've got a mouse nest or (expired) rodent too big to fit
between the blades bouncing around in the fan?
Reasonable - any chance the motor mounts are dying and under some conditions part of the set - usually the starter housing - is
occasionally bumping the drawer?
Quick n dirty way to test - take a crowbar or large screwdriver, fire it up, and then lift and twist and pry and see if you can get
it to make the sound. How you move it to do so will clue you as to what's hitting and you can go find it.
--johnny
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Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240274 is a reply to message #240240] |
Mon, 17 February 2014 12:50 |
Carl S.
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
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Senior Member |
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"Oil leaks are 80% coming from the oil filter adapter, not the main crank
seal."
The most likely place for a leak in that area is where the oil filter adapter bolts to the engine. There is a mount sandwiched between the engine and the adapter with a gasket on either side of it. Both gaskets need to be replaced. One of the nuts is hard to get at, but it can be accessed with a distributor wrench (1/2" IIRC).
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Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240277 is a reply to message #240240] |
Mon, 17 February 2014 18:25 |
John Olson
Messages: 96
Registered: August 2013
Karma: 0
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Member |
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Carl - thanks for the tips, I'll keep both gaskets in mind when ordering
parts.
Larry - Nope, water heater was off. This was definitely Onan related.
John O
On Mon, Feb 17, 2014 at 5:18 PM, Larry Davick <ljdavick@comcast.net> wrote:
> Could the thump be coming from somewhere else -maybe the water heater?
>
> Larry Davick
> A Mystery Machine
> 1976(ish) Palm Beach
> Fremont, CA
>
> > On Feb 16, 2014, at 11:44 AM, John Olson <johnolsondesign@gmail.com>
> wrote:
> >
> > Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan
> Wash
> > BLM in Quartzite.
> >
> > Today is running seemingly fine, but from inside the coach, I hear an
> > intermittent sound I can best describe as
> > *similar to a small shoe tumbling in a dryer. *
> > Irregular faint thump sound. Normal sound for 15-25 seconds, faint and
> > irregular thump for 5-10 seconds. Repeat.
> >
> > NOT engine lope sound. Engine hum is consistent...no loping.
> >
> >
> > Onan links and info has been collected. Have read manuals,
> troubleshooting
> > guides.
> >
> > The community guides to onan are great resources, but it seems to run
> fine
> > according to troubleshooter items (starting, power output, pressure,
> etc.).
> >
> >
> > Checked oil. Needs changing, but is full. Will change asap.
> >
> > Air filter has some dust but is not caked. Will clean/replace.
> >
> > Plugs are rusted in wrench collar area but seem to work ok. Will replace
> > asap.
> >
> >
> >
> > John Olson
> > 76 Edgemont (the one with the minor thumping Onan)
> > Chicago, IL (currently in Scaddan Wash BLM in Quartzite)
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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John Olson
76 Edgemonte
Fulltime traveler
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240281 is a reply to message #240240] |
Mon, 17 February 2014 01:57 |
John Olson
Messages: 96
Registered: August 2013
Karma: 0
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Member |
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Rob - great analysis and explanation. Your dogged dedication to the GMC
community and specifically my problem has not gone unnoticed by this one.
Motor mounts, while visibly checked, still seem tightly intact and somewhat
functional. Ill jury rig the choke magnet in place and see how the Onan
improves.
Will check behind the air cooler shroud for the items you mentioned.
Jim - yes, the origin of oil weeping does appear to be centered from
business end of oil filter, now that you mention it. I'll have a look.
Thanks for the help.
On Sunday, February 16, 2014, Jim Kanomata <jimkanomata@gmail.com> wrote:
> check the muffler for bumping noise.
> Oil leaks are 80% coming from the oil filter adapter, not the main crank
> seal.
>
>
>
> On Sun, Feb 16, 2014 at 7:47 PM, Robert Mueller <robmueller@iinet.net.au<javascript:;>
> >wrote:
>
> > John,
> >
> > Yes that is the electro magnet part of the electric choke. I would
> suggest
> > you disconnect the wire that is going to it and connect
> > that tab to 12 vdc positive and ground the case to see if the center pole
> > becomes magnetic. If it does you could then figger out how
> > to reattach it to the body that is still mounted to the exhaust manifold.
> > Keep in mind that it gets HOT!
> >
> > Remove the air cooling shroud over the rear cylinder
> >
> >
> >
> http://www.gmcmhphotos.com/photos/1976-gmc-mobile-city-hall/p51309-image100.html
> >
> > and you will expose the oil filter mount and oil pressure switch, it is
> > quite common for the oil pressure switch to develop a leak
> > where the phenolic material meets the metal base.
> >
> > New / old Onan mounts:
> >
> >
> >
> http://www.gmcmhphotos.com/photos/onan-mount-replacement/p43907-onan-mounts.html
> >
> > Regards,
> > Rob M.
> > Sydney, Australia
> > AUS '75 Avion - The Blue Streak TZE365V100428
> > USA '75 Avion - Double Trouble TZE365V100426
> >
> > -----Original Message-----
> > From: John Olson
> >
> > Pics of oil leaking issues and a cracked Electric Choke (I think thats
> > what it is).
> >
> > http://www.gmcmhphotos.com/photos/g6541-onan-issues.html
> >
> > Ideas about how to stop the leaking and fix the broken choke part?
> >
> > John
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> >
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com <javascript:;>
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
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>
--
John Olson
Cell | 773.315.9220
Skype | johnolsondesign
http://www.linkedin.com/in/johnolsondesign
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John Olson
76 Edgemonte
Fulltime traveler
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240282 is a reply to message #240240] |
Sun, 16 February 2014 23:55 |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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Senior Member |
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check the muffler for bumping noise.
Oil leaks are 80% coming from the oil filter adapter, not the main crank
seal.
On Sun, Feb 16, 2014 at 7:47 PM, Robert Mueller <robmueller@iinet.net.au>wrote:
> John,
>
> Yes that is the electro magnet part of the electric choke. I would suggest
> you disconnect the wire that is going to it and connect
> that tab to 12 vdc positive and ground the case to see if the center pole
> becomes magnetic. If it does you could then figger out how
> to reattach it to the body that is still mounted to the exhaust manifold.
> Keep in mind that it gets HOT!
>
> Remove the air cooling shroud over the rear cylinder
>
>
> http://www.gmcmhphotos.com/photos/1976-gmc-mobile-city-hall/p51309-image100.html
>
> and you will expose the oil filter mount and oil pressure switch, it is
> quite common for the oil pressure switch to develop a leak
> where the phenolic material meets the metal base.
>
> New / old Onan mounts:
>
>
> http://www.gmcmhphotos.com/photos/onan-mount-replacement/p43907-onan-mounts.html
>
> Regards,
> Rob M.
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
> -----Original Message-----
> From: John Olson
>
> Pics of oil leaking issues and a cracked Electric Choke (I think thats
> what it is).
>
> http://www.gmcmhphotos.com/photos/g6541-onan-issues.html
>
> Ideas about how to stop the leaking and fix the broken choke part?
>
> John
>
> _______________________________________________
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240294 is a reply to message #240282] |
Mon, 17 February 2014 21:30 |
tphipps
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
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Senior Member |
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Replacement gasket for oil filter is easy to obtain. Go to Wal-Mart and buy new Fram filter for engine. Remove rubber ring, toss away filter. Remove mount, replace rubber ring, tighten oil filter adapter. Use real oil filter for engine. Remember to refill with oil.
Tom, MS II
2012 Phoenix Cruiser model 2552
KA4CSG
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240300 is a reply to message #240240] |
Mon, 17 February 2014 22:03 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
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Senior Member |
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| John Olson wrote on Sun, 16 February 2014 12:44 |
Our Onan 6kw ran fine for a couple hours yesterday. Parked in Scaddan Wash
BLM in Quartzite.
Today is running seemingly fine, but from inside the coach, I hear an
intermittent sound I can best describe as
*similar to a small shoe tumbling in a dryer. *
Irregular faint thump sound. Normal sound for 15-25 seconds, faint and
irregular thump for 5-10 seconds. Repeat.
NOT engine lope sound. Engine hum is consistent...no loping.
Onan links and info has been collected. Have read manuals, troubleshooting
guides.
The community guides to onan are great resources, but it seems to run fine
according to troubleshooter items (starting, power output, pressure, etc.).
Checked oil. Needs changing, but is full. Will change asap.
Air filter has some dust but is not caked. Will clean/replace.
Plugs are rusted in wrench collar area but seem to work ok. Will replace
asap.
John Olson
76 Edgemont (the one with the minor thumping Onan)
Chicago, IL (currently in Scaddan Wash BLM in Quartzite)
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I had a similar problem and it was the outer front cover of the Onan hitting the generator door. I ran it with the Onan pulled out and it went away. It can also be the Onan hitting the frame rail. Again, run it with the generator pulled out and check again.
Bob de Kruyff
78 Eleganza
Chandler, AZ
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240301 is a reply to message #240240] |
Mon, 17 February 2014 22:08 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
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Senior Member |
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Your choke is definitely toast. You can still find them on Ebay and I recently saw 2 new ones for sale. I just sold my 1 yr old choke. As far as leaks, make sure you also check the governor housing bolts. mine were finger tight.
Bob de Kruyff
78 Eleganza
Chandler, AZ
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| Re: [GMCnet] Onan bumping/knocking sound? [message #240313 is a reply to message #240309] |
Tue, 18 February 2014 00:49 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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| John Olson wrote on Mon, 17 February 2014 23:11 |
Thanks Bob. You may be right about the thumping being interference with gen
door. Last run, I opened the door to see the onan front panel vibrating
baaadly. Shut it down and thats when I found the broken choke wedged
against the outer onan door.
I did find a Sisson manufacturing replacement NOS choke after a quick look
on ebay but had no idea they were made of gold ($225...at least they give
free shipping!).
http://www.ebay.com/itm/153-0233-ONAN-SISSON-CHOKE-12-volt-PIERCE-GOVERNOR-CO-New-Old-Stock-/141184724573?pt=LH_DefaultDomain_0&hash=item20df43ee5 d
Anyone want a mostly running Onan? It's not about the $225...I've been
considering alternatives for power generation and that Onan space for a bit
now.
John Olson
76 Edgemont
Chicago, IL (currently in Lake Pleasant ST Park AZ)
On Mon, Feb 17, 2014 at 9:08 PM, Bob de Kruyff <NEXT2POOL@aol.com> wrote:
>
>
> Your choke is definitely toast. You can still find them on Ebay and I
> recently saw 2 new ones for sale. I just sold my 1 yr old choke. As far as
> leaks, make sure you also check the governor housing bolts. mine were
> finger tight.
> --
> Bob de Kruyff
> 78 Eleganza
> Chandler, AZ
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John, Do not scrap that Onan.
I could use some parts off of it.
Are you giving it away or trying to sell it?
I'll Gladly travel to Chicago but, not Arizona, I'll even help you remove it. I have an engine hoist that we could use to snatch it out of there.
What are you thinking of replacing it with?
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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