| Problem #1 Odd noise [message #218676] |
Fri, 16 August 2013 21:09  |
kerry pinkerton
Messages: 2565
Registered: July 2012
Location: Harvest, Al
Karma: 15
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Today I made a 100 mile shakedown trip to have lunch with Tom and Mark. The new 403/tranny/diff ran great. HOWEVER...
There is the odd noise at about 2700 RPM UNDER LOAD. It's kind of a chuff chuff sound....a bit like a small steam engine...a couple three per second. In the driveway there is no noise at any RPM other than the engine just running. Dropping in neutral at speed stops the noise but revving the motor will bring it back. Don't understand why I can get it freewheeling down the highway in neutral but not parked in the driveway.
It's an odd sound. Not that loud but annoying.
Suspects are loose or faulty spark plugs letting air out. Doubtful but I'll pull them tomorrow and check.
Exhaust leak...I'll re-torque and verify the bolts are not bottoming out.
I don't have the wheel liners and thought it might be some kind of acoustic thing but that would not fit with it going away when I shifted to neutral.
I'll get someone to drive and I'll pull the hatch and listen with a piece of heater hose to my ear.
Anyone run into anything like this or have any thoughts????
Kerry Pinkerton - North Alabama
Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
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| Re: Problem #1 Odd noise [message #218685 is a reply to message #218676] |
Fri, 16 August 2013 21:51  |
Dennis S
Messages: 3046
Registered: November 2005
Karma: 2
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Senior Member |
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The exhaust donuts (between the manifold and the down pipe) sometimes seem difficult to seat -- I had to rotate one on mine several degrees in order to get a good seal.
Dennis
| Kerry Pinkerton wrote on Fri, 16 August 2013 21:09 |
Today I made a 100 mile shakedown trip to have lunch with Tom and Mark. The new 403/tranny/diff ran great. HOWEVER...
There is the odd noise at about 2700 RPM UNDER LOAD. It's kind of a chuff chuff sound....a bit like a small steam engine...a couple three per second. In the driveway there is no noise at any RPM other than the engine just running. Dropping in neutral at speed stops the noise but revving the motor will bring it back. Don't understand why I can get it freewheeling down the highway in neutral but not parked in the driveway.
It's an odd sound. Not that loud but annoying.
Suspects are loose or faulty spark plugs letting air out. Doubtful but I'll pull them tomorrow and check.
Exhaust leak...I'll re-torque and verify the bolts are not bottoming out.
I don't have the wheel liners and thought it might be some kind of acoustic thing but that would not fit with it going away when I shifted to neutral.
I'll get someone to drive and I'll pull the hatch and listen with a piece of heater hose to my ear.
Anyone run into anything like this or have any thoughts????
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Dennis S
73 Painted Desert 230
Memphis TN Metro
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| Re: Problem #1 Odd noise [message #218760 is a reply to message #218676] |
Sat, 17 August 2013 13:15 |
kerry pinkerton
Messages: 2565
Registered: July 2012
Location: Harvest, Al
Karma: 15
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Senior Member |
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At the moment Bo and I (my neighbor) are thinking it's acoustical resonance of some type. It could have been there all along but the other motor was louder and we just couldn't hear it. Or it could be something with the fender liners. We drove with the hatch down and heard it. We the hatch off, same road, same speed, and could not.
Alternator fan not scraping. Fan not hitting the shroud. Can't see or find any exhaust leaks.
I'm just going to drive it a while.
Kerry Pinkerton - North Alabama
Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
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