| Whine [message #268168] |
Wed, 24 December 2014 14:02  |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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I noticed on the way back from The Mouse, a whine coming from someplace. My impression is left forward area, but I haven't had time to run the coach and pin it down. I am puzzled because it appears around 45 MPH, disappears around 50+. It does >not< change with engine load which to me discounts the differential and transmission. It also doesn't change when the coach is side loaded, which to me discounts a wheel bearing. But, I'm open to suggestions. The tires are unchanged from my last trip down there which didn't whine, so I don't think they're culprits either. I was towing a Kia Soul instead of the Ranger pickup, again both about the same weight.
I propose to change the differential oil, it's probably due, I'll note if things change. I've added flating backing plates on the rear drums, I don't >think< I screwed up the bearings beyond the one which failed. Checking is in order even though none are running hotter than the others.
What might cause a whine at a particular speed which loading doesn't affect?
--johnny
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: Whine [message #268199 is a reply to message #268186] |
Wed, 24 December 2014 21:00  |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Two things.
Most noises like that I eventually track down to be tires.
Second, I have an outside mirror that does something like that. The mirror is easy to check. Just drive it until it makes noise and then open the window Put your hand on it to dampen the vibration and see if it goes away. Mine is the right side Ramco mirror that does it.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: Whine [message #268213 is a reply to message #268199] |
Thu, 25 December 2014 02:57 |
Bullitthead
Messages: 1411
Registered: November 2013
Karma: 5
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My thick CB antenna makes a low hum that sounds like a bearing and the thin CB antenna makes a higher pitched sound that some might think was 2 gears meshing at high RPMs. Either one of them only does it at certain speeds above a threshold of about 39 MPH.
One time I got a plastic bag stuck on the front of the grille on the car and it changed the normal sound for me, nobody else in the car noticed the change.
A lot of times a vacuum leak can cause those sounds too.
Terry Kelpien
ASE Master Technician
73 Glacier 260
Smithfield, Va.
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| Re: Whine [message #268220 is a reply to message #268168] |
Thu, 25 December 2014 09:18 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Senior Member |
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No change to the roof or mirrors (Ramcos) so I doubt them as a source. Same tyres and wheels. HOWever, I did change the CB antenna at Bean Station. And it's on the left mirror arm. Tests are scheduled.
Thanks!
--johnny
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] Whine [message #268225 is a reply to message #268223] |
Thu, 25 December 2014 10:15 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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If you think it is the CB antenna, put something on it to change it's resonate audio, not RF, frequency. A 2" piece of shrink tubing on the top would do. For a test just install a piece of tape on it.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: Whine [message #268228 is a reply to message #268168] |
Thu, 25 December 2014 10:53 |
midlf
Messages: 2212
Registered: July 2007
Location: SE Wisc. (Palmyra)
Karma: 1
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Senior Member |
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My wind wing shifted and was hittting the loose toll window. repositioning the wing, until it moved back, killed the noise. replacing the weather strip cured it.
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
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