| Vibration [message #341083] |
Sat, 16 February 2019 18:44  |
Nicholls
Messages: 36
Registered: January 2008
Location: Pensacola, FL
Karma: 0
|
Member |
|
|
I am stumped. Severe vibration at 35 which goes away at 45. Quite violent. Ran with the hatch open today and it is the engine. Had thought it was tires but complete balance Friday killed that theory. What would make the engine shudder so and then go away. Comments and suggestions most appreciated.
John Nicholls,
78 Royale w/455
Pensacola, FL
|
|
|
|
| Re: [GMCnet] Vibration [message #341084 is a reply to message #341083] |
Sat, 16 February 2019 18:46  |
Dolph Santorine
Messages: 1236
Registered: April 2011
Location: Wheeling, WV
Karma: -41
|
Senior Member |
|
|
Did you check the CV shafts? I’m thinking one of the inners.
Dolph
DE AD0LF
Wheeling, West Virginia
1977 26’ ex-PalmBeach
Howell EFI & EBL, Reaction Arms, Sullybilt Bags, Manny Transmission
“The Aluminum and Fiberglass Mistress"
> On Feb 16, 2019, at 7:44 PM, John Nicholls via Gmclist wrote:
>
> I am stumped. Severe vibration at 35 which goes away at 45. Quite violent. Ran with the hatch open today and it is the engine. Had thought it was
> tires but complete balance Friday killed that theory. What would make the engine shudder so and then go away. Comments and suggestions most
> appreciated.
> --
> John Nicholls,
> 78 Royale w/455
> Pensacola, FL
>
> _______________________________________________
> 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
|
|
|
|
| Re: [GMCnet] Vibration [message #341086 is a reply to message #341084] |
Sat, 16 February 2019 19:05 |
bdub
Messages: 1578
Registered: February 2004
Location: Central Texas
Karma: 5
|
Senior Member |
|
|
Very possible. At Amana a guy had that same situation. Sure enough, got
it outta there and it was falling apart with dried up grease.
John Lebetski can tell ya more. I think it was on the passenger side.
Gotta lift it up and listen to both sides with a hose or screwdriver
(hillbilly stethoscope).
bdub
On Sat, Feb 16, 2019 at 6:47 PM Dolph Santorine via Gmclist <
gmclist@list.gmcnet.org> wrote:
> Did you check the CV shafts? I’m thinking one of the inners.
>
>
> Dolph
>
> DE AD0LF
>
> Wheeling, West Virginia
>
> 1977 26’ ex-PalmBeach
> Howell EFI & EBL, Reaction Arms, Sullybilt Bags, Manny Transmission
>
> “The Aluminum and Fiberglass Mistress"
>
>> On Feb 16, 2019, at 7:44 PM, John Nicholls via Gmclist gmclist@list.gmcnet.org> wrote:
>>
>> I am stumped. Severe vibration at 35 which goes away at 45. Quite
> violent. Ran with the hatch open today and it is the engine. Had thought
> it was
>> tires but complete balance Friday killed that theory. What would make
> the engine shudder so and then go away. Comments and suggestions most
>> appreciated.
>> --
>> John Nicholls,
>> 78 Royale w/455
>> Pensacola, FL
>>
>> _______________________________________________
>> 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
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
bdub
'76 Palm Beach/Central Texas
www.bdub.net
www.gmcmhphotos.com
www.gmcmotorhomemarketplace.com
www.gmcmhregistry.com
www.facebook.com/groups/classicgmcmotorhomes
www.facebook.com/groups/gmcmm
|
|
|
|
| Re: Vibration [message #341087 is a reply to message #341083] |
Sat, 16 February 2019 19:10 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
Tire(s) out of round. Put front tires on rear and rear tires on front.
Front ride height can cause some strange things like that. At least measure it to see if it is way off.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
|
|
|
|
|
|
| Re: Vibration [message #341091 is a reply to message #341083] |
Sun, 17 February 2019 09:45 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
|
Senior Member |
|
|
With an assistant, hatch off, drive through that speed range and observe the axle shafts for any eliptical (out of round) motion. If the needle bearings on the inner joint have failed the shaft can run off center and bind as far as free in and out telescopic motion. This will bind and cause the entire powertrain to waddle on it's mounts. Also inspect the pass side support bearing to be sure the 3 bolts are snug. Also inspect that the flange bolts are all present on both axle to final drive flanges. These can come loose if not installed correctly and cause excentric motion before failure.
John Lebetski
Woodstock, IL
77 Eleganza II
|
|
|
|
| Re: Vibration [message #341097 is a reply to message #341083] |
Sun, 17 February 2019 13:21 |
C Boyd
Messages: 2629
Registered: April 2006
Karma: 18
|
Senior Member |
|
|
Hi John. It seems if the vibration was in the engine it would be an rpm vibration and would vibrate at that rpm in each gear. A mph only vibration seems would be between the engine and the wheels. Physically get your hands on the shafts and joints and mid shaft bearings and try hard to find loose motion. Check the differential mounts and bolts. Inner cv bolts..
Nicholls wrote on Sat, 16 February 2019 19:44I am stumped. Severe vibration at 35 which goes away at 45. Quite violent. Ran with the hatch open today and it is the engine. Had thought it was tires but complete balance Friday killed that theory. What would make the engine shudder so and then go away. Comments and suggestions most appreciated.
C. Boyd
76 Crestmont
East Tennessee
|
|
|
|
|
|
| Re: [GMCnet] Vibration [message #341106 is a reply to message #341099] |
Sun, 17 February 2019 19:07 |
Nicholls
Messages: 36
Registered: January 2008
Location: Pensacola, FL
Karma: 0
|
Member |
|
|
Thanks all.
No loose bolts connecting inner cv joint to final drive, FD,. Did try to move the joints and there was some looseness on the drivers side at the FD but all FDs that I have touched have some movement where the axle connects.
Checked tires for out of round while having them balanced. Ride height is low (3/8) on both sides and hace adjusted rears down also but has been like that for years.
Would a slipped harmonic balancer affect only a specific speed range?
Removal of the axle is the next step but prior to that I am going to run a compression test to rule out anything like a misfire although one would expect that to be worse at idle ( I think ).
John Nicholls,
78 Royale w/455
Pensacola, FL
|
|
|
|
| Re: [GMCnet] Vibration [message #341108 is a reply to message #341106] |
Sun, 17 February 2019 19:32 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
John,
You haven't stated whether the vibration occurs when you rev the engine
through the 35 mph rpm range. Seems to me that might narrow the problem to
engine or running gear.
Ken H.
On Sun, Feb 17, 2019 at 8:22 PM John Nicholls via Gmclist <
gmclist@list.gmcnet.org> wrote:
> Thanks all.
> No loose bolts connecting inner cv joint to final drive, FD,. Did try to
> move the joints and there was some looseness on the drivers side at the FD
> but all FDs that I have touched have some movement where the axle connects.
> Checked tires for out of round while having them balanced. Ride height is
> low (3/8) on both sides and hace adjusted rears down also but has been like
> that for years.
> Would a slipped harmonic balancer affect only a specific speed range?
> Removal of the axle is the next step but prior to that I am going to run a
> compression test to rule out anything like a misfire although one would
> expect that to be worse at idle ( I think ).
> --
> John Nicholls,
> 78 Royale w/455
> Pensacola, FL
>
> _______________________________________________
> 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
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
|
|
|
|
| Re: Vibration [message #341115 is a reply to message #341083] |
Mon, 18 February 2019 08:37 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
|
Senior Member |
|
|
Try using a different gear when it happens. That will help determine if engine or after engine.
John Lebetski
Woodstock, IL
77 Eleganza II
|
|
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
