Shock mount failure

[Pete Masterson]

Sounds exactly like what happened when my shock mount failed. Bent the shock upper fitting and took out the air line. Fortunately for me, the failure actually occurred at the CCW facility while moving the coach from one service point to another. (I had noted an odd "popping" sound that seemed like it was coming from the passenger side suspension -- but that was an illusion as the "popping sound" was probably the last bit of the shock mount giving way on the left... Of course, the CCW folks had thoroughly checked the right side finding nothing significant...)

Be sure that the welder adds a couple of gussets to strengthen the weld -- Henderson's in Grants Pass had earlier welded the crack (short of complete failure) 6 months earlier, but their weld was insufficient.

I've subsequently inspected the rewelded mount several times, and it looks clean and appears to be holding.

I guess the caution here is for all the Wide Body owners to check the driver's side front shock mount and carefully examine the area around the mount for cracks. If the issue is caught before failure, you're likely to avoid having to pay for a new shock, because the failure mode seems to always bend the top of the shock.

The failure is in a Ridewell component that, frankly, was of insufficient strength for the loads applied.

Pete Masterson

'95 Blue Bird Wanderlodge WBDA 42 (For Sale)

<http://www.aeonix.biz/BBforsale.html>

El Sobrante CA

"aeonix1@mac.com"

On Feb 18, 2009, at 1:50 PM, Don Bradner wrote:

I'm the latest victim of a driver's side front shock mount failure. It took out the brake line when it went. I was not far from home on the way back from Q, so I limped on in (I know, in retrospect it was too dangerous, but I kept a lonnnng following distance!)

I've used the local Detroit dealer in Arcata (Trinity Diesel) a couple of times now for service, so I called them, and the service manager said he would swing by for a look, no charge. He ended up removing the shock and the air line, and said that he would come by the next time he was this way with a new airline. A new shock will have to be ordered (the top bent/caved in) and they will schedule an appointment to get it welded after they have that. Shock was 17 months old.


Don Bradner
90 PT40 "Blue Thunder"
My location: www.bbirdmaps.com/user2.cfm?user=1

[Pete Masterson]

Ernie, it's not the shock, it's the upper shock mount. See the photos on my web page:

<http://homepage.mac.com/aeonix1/PhotoAlbum11.html>

One photo 01, 02, and 04, I've outlined the added gussets in blue and drawn a line in yellow showing the crack that developed.

Note: For those who notice, the locknut was replaced since the photos. The technician put 2 washers on when only one should have been used*, making the locknut not fully engage. A new locknut should always be used in this application.

*The shock mount has a smooth, round landing zone for the shock to press against. Only one washer, on the outside is needed. But the inclination would be to use two washers, but then the locknut won't tighten fully to engage the locking threads.

===============================================

Pete Masterson, Author of

Book Design and Production: A Guide for Authors and Publishers

"Aeonix1@Mac.com"

Aeonix Publishing Group http://www.aeonix.com

===============================================

On Feb 18, 2009, at 1:59 PM, Ernie Ekberg wrote:

Don, that is a first for me hearing that. Is this a Koni? Ernie Ekberg 83PT40 Wanderlodge Weatherford, Tx http://autos.groups.yahoo.com/group/erni...gandrepair --- OnWed, 2/18/09, Don Bradner<"bluethunder@arcatapet.com">wrote: From: Don Bradner <"bluethunder@arcatapet.com"> Subject: [WanderlodgeForum] Shock mount failure To:"WanderlodgeForum@yahoogroups.com" Date: Wednesday, February 18, 2009, 3:50 PM I'm the latest victim of a driver's side front shock mount failure. It took out the brake line when it went. I was not far from home on the way back from Q, so I limped on in (I know, in retrospect it was too dangerous, but I kept a lonnnng following distance!) I've used the local Detroit dealer in Arcata (Trinity Diesel) a couple of times now for service, so I called them, and the service manager said he would swing by for a look, no charge. He ended up removing the shock and the air line, and said that he would come by the next time he was this way with a new airline. A new shock will have to be ordered (the top bent/caved in) and they will schedule an appointment to get it welded after they have that. Shock was 17 months old. Don Bradner 90 PT40 "Blue Thunder" My location: http://www.bbirdmaps. com/user2. cfm?user= 1

[Pete Masterson]

Looks damn near identical to the one I had... Only I was lucky and it happened in CCW's parking lot.

Pete Masterson

'95 Blue Bird Wanderlodge WBDA 42 (For Sale)

<http://www.aeonix.biz/BBforsale.html>

El Sobrante CA

"aeonix1@mac.com"

On Feb 18, 2009, at 2:24 PM, David Brady wrote:

Wow Don, did you really drive like that? That's gotta be the most
severe case of the dreaded shock mount crack that I've ever
seen on a Wide Body. There must have been symptoms, creaks,
popping sounds, etc. Oh, keeping some paint on the frame definitely
prolongs the life of those welds. I'd get on the phone with Ridewell
to procure a replacement for the spring perch and shock mount
component. I think that piece is a bolt on.

David Brady
'02 LXi, NC

-----Original Message-----
From: Don Bradner
Sent: Feb 18, 2009 5:13 PM
To:"WanderlodgeForum@yahoogroups.com"
Subject: Re: [WanderlodgeForum] Shock mount failure

Yes, it is Koni. The failure is similar to ones described by others here.

Photo:http://www.arcatapet.net/image/shockmount.jpg

On 2/18/2009 at 1:59 PM Ernie Ekberg wrote:

>Don, that is a first for me hearing that. Is this a Koni?
>
>
>Ernie Ekberg
>83PT40
>Wanderlodge
>Weatherford, Tx
>http://autos.groups.yahoo.com/group/erniesremodelingandrepair
>
>--- On Wed, 2/18/09, Don Bradner <"bluethunder%40arcatapet.com"> wrote:
>
>From: Don Bradner <"bluethunder%40arcatapet.com">
>Subject: [WanderlodgeForum] Shock mount failure
>To:"WanderlodgeForum%40yahoogroups.com"
>Date: Wednesday, February 18, 2009, 3:50 PM
>
>
>
>
>
>
>I'm the latest victim of a driver's side front shock mount failure. It
>took out the brake line when it went. I was not far from home on the way
>back from Q, so I limped on in (I know, in retrospect it was too
>dangerous, but I kept a lonnnng following distance!)
>
>I've used the local Detroit dealer in Arcata (Trinity Diesel) a couple of
>times now for service, so I called them, and the service manager said he
>would swing by for a look, no charge. He ended up removing the shock and
>the air line, and said that he would come by the next time he was this way
>with a new airline. A new shock will have to be ordered (the top
>bent/caved in) and they will schedule an appointment to get it welded
>after they have that. Shock was 17 months old.
>
>Don Bradner
>90 PT40 "Blue Thunder"
>My location: http://www.bbirdmaps. com/user2. cfm?user= 1

[Pete Masterson]

This is a "known issue" with the wide body 'birds. Might not affect the BMC since they use the Spartan chassis.

Pete Masterson

'95 Blue Bird Wanderlodge WBDA 42 (For Sale)

<http://www.aeonix.biz/BBforsale.html>

El Sobrante CA

"aeonix1@mac.com"

On Feb 18, 2009, at 2:58 PM, martingregg598 wrote:

Hi Don, sorry to here about the failure, can't help but wonder if
putting on shocks that dial-up the compression and rebound to improve
ride and handling, exceeds the design specification of the bracket, or
maybe it was a bad weld procedure. I know one thing, I will be keeping
an eye on mine!
Marty Gregg
95 BMC 37
Kennewick WA

[Don Bradner]

I went in and looked from the underside when I didn't know what the problem was,
but my best look at things came with blind camera shots over the top of the
tires. I took many pictures at various angles, and also did this on the
passenger side. This is an example of the way that side looks, and demonstrates
the significant differences: http://www.arcatapet.net/image/goodmount.jpg

On 2/18/2009 at 3:13 PM Leroy Eckert wrote:

>I agree David. When it dries out around here I am gonna take a look at
>mine..
>Leroy Eckert
>1990 WB-40 Smoke N Mirrors
>Dahlonega, GA
>Royale Conversion
>
>--- On Wed, 2/18/09, David Brady wrote:
>From: David Brady
>Subject: Re: [WanderlodgeForum] Shock mount failure
>To: WanderlodgeForum@yahoogroups.com
>Date: Wednesday, February 18, 2009, 5:51 PM
>
>
>
>
>
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>
>
>
>
> I'm not a metallurgist, but from the looks of the rust on the
>crack
>edges, this failure has been developing for some time. Okay
>everyone, it's time to crawl under your bus to check the steer
>axle, street side shock mount for cracks.
>
>David
>'02 LXi, NC
>
>
>-----Original Message-----
>
>From: Don Bradner
>
>Sent: Feb 18, 2009 5:47 PM
>
>To: WanderlodgeForum@ yahoogroups. com
>
>Subject: Re: [WanderlodgeForum] Shock mount failure
>
>
>
>
>
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> I'm not sure it is worse than others. The thing is I don't
>think anyone has shown theirs pre-fix before. If you look at Pete
>Masterson's http://homepage. mac.com/aeonix1/ Sites-Pages/ Image2.html you
>will see that the tear is almost identical in location and scope as mine.
>In the Bumpersbird album I can't really tell where the tear was (and it
>may not have torn off).
>
>
>
>On 2/18/2009 at 5:24 PM David Brady wrote:
>
>
>
>>That's gotta be the most
>
>>severe case of the dreaded shock mount crack that I've ever
>
>>seen on a Wide Body.
>
>
>
>Don Bradner
>
>90 PT40 "Blue Thunder"
>
>My location: http://www.bbirdmaps. com/user2. cfm?user= 1

[Kurt Horvath]

Welcome to the club Don.
There are a few photos of the welded mount in my album ( Bumpersbird )
Look for #22, #44
Did it smash the brake line or did it tear off.
Running without one brake is dooable with care as you said.
Not an uncommon occurance according to some shops. just plug the line
and go, slower of course.
The cheepest new Konis were at BB. Now that's not an option, If time
allows shop around, prices varied by 50 -60% when I went shopping to
replace mine.

Kurt Horvath
95 PT-42
10AC

[Don Bradner]

I wouldn't call it smash or tear - it was a very sharp edge on that contact
point that gouged the line.

List for that shock is $197 - I suspect that will be a lot less than the labor
of the fix!

On 2/19/2009 at 1:04 AM Kurt Horvath wrote:

>Welcome to the club Don.
>There are a few photos of the welded mount in my album ( Bumpersbird )
>Look for #22, #44
>Did it smash the brake line or did it tear off.
>Running without one brake is dooable with care as you said.
>Not an uncommon occurance according to some shops. just plug the line
>and go, slower of course.
>The cheepest new Konis were at BB. Now that's not an option, If time
>allows shop around, prices varied by 50 -60% when I went shopping to
>replace mine.
>
>Kurt Horvath
>95 PT-42
>10AC
>
>
>
>------------------------------------
>
>Yahoo! Groups Links
>
>
>

[david brady]

Don,



If you send a pic to Ridewell they may give you a new piece.



The curb side upper shock mount is different due to the location

of the panhard rod frame pivot.



David Brady

'02 LXi, NC







Don Bradner wrote:

I went in and looked from the underside when I didn't know what
the problem was, but my best look at things came with blind camera
shots over the top of the tires. I took many pictures at various
angles, and also did this on the passenger side. This is an example of
the way that side looks, and demonstrates the significant differences: http://www.arcatapet.net/image/goodmount.jpg



On 2/18/2009 at 3:13 PM Leroy Eckert wrote:



>I agree David. When it dries out around here I am gonna take a look
at

>mine..

>Leroy Eckert

>1990 WB-40 Smoke N Mirrors

>Dahlonega, GA

>Royale Conversion

>

>--- On Wed, 2/18/09, David Brady <"dmb993%40earthlink.net">
wrote:

>From: David Brady <"dmb993%40earthlink.net">

>Subject: Re: [WanderlodgeForum] Shock mount failure

>To: "WanderlodgeForum%40yahoogroups.com"

>Date: Wednesday, February 18, 2009, 5:51 PM

>

>

>

>

>

>

>

>

>

>

>

>

> I'm not a metallurgist, but from the looks of the rust on the

>crack

>edges, this failure has been developing for some time. Okay

>everyone, it's time to crawl under your bus to check the steer

>axle, street side shock mount for cracks.

>

>David

>'02 LXi, NC

>

>

>-----Original Message-----

>

>From: Don Bradner

>

>Sent: Feb 18, 2009 5:47 PM

>

>To: WanderlodgeForum@ yahoogroups. com

>

>Subject: Re: [WanderlodgeForum] Shock mount failure

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

> I'm not sure it is worse than others. The thing is I don't

>think anyone has shown theirs pre-fix before. If you look at Pete

>Masterson's http://homepage.
mac.com/aeonix1/ Sites-Pages/ Image2.html you

>will see that the tear is almost identical in location and scope as
mine.

>In the Bumpersbird album I can't really tell where the tear was
(and it

>may not have torn off).

>

>

>

>On 2/18/2009 at 5:24 PM David Brady wrote:

>

>

>

>>That's gotta be the most

>

>>severe case of the dreaded shock mount crack that I've ever

>

>>seen on a Wide Body.

>

>

>

>Don Bradner

>

>90 PT40 "Blue Thunder"

>

>My location: www.bbirdmaps. com/user2. cfm?user= 1

No virus found in this incoming message.

Checked by AVG. Version: 7.5.552 / Virus Database: 270.10.23/1952 - Release Date: 2/13/2009 6:29 PM

[timvasqz]

I think the crack was there from off-camber HWH jack parking in the
past. looks like the temper of the weld proved a brittle spot that
under normal conditions would not have issue. Then the new shock
absorbed more bounce but reacted equally agressive causing much more
stress on the mount. I think the mount post should have less strength
and be a point that can bend at failure. the tripod gussettes are a
bad idea.

I think problems arise when the bus air bags are dropped to be
leveled but the spot is too off camber. the HWH push one side up
and tilt the axle too much. at that point raising the front is
effortless and and the 30 foot lever post all the stress on the
tucked tire.

If I was to repair that mount I would remove two bolts and make a
trapazoid shape cut and replace the plate with a butt weld then build
the post mount back no better than before.

If you lose an airline and must drive. there is a screw set in the
maxicam to turn off the parking brake. you can then plug the airline
and fold it over then tape it.
Greg ofTim&Greg
94ptca





.--- In WanderlodgeForum@yahoogroups.com, "Don Bradner"
wrote:
>
> I'm the latest victim of a driver's side front shock mount failure.
It took out the brake line when it went. I was not far from home on
the way back from Q, so I limped on in (I know, in retrospect it was
too dangerous, but I kept a lonnnng following distance!)
>
> I've used the local Detroit dealer in Arcata (Trinity Diesel) a
couple of times now for service, so I called them, and the service
manager said he would swing by for a look, no charge. He ended up
removing the shock and the air line, and said that he would come by
the next time he was this way with a new airline. A new shock will
have to be ordered (the top bent/caved in) and they will schedule an
appointment to get it welded after they have that. Shock was 17
months old.
>
>
> Don Bradner
> 90 PT40 "Blue Thunder"
> My location: http://www.bbirdmaps.com/user2.cfm?user=1
>

[david brady]

Greg,



I don't think the axle tilt puts undo stress on the shock. If you

consider the steer axle in full droop on one side and full bump on

the other. The angle of the axle is roughly 5 deg to the horizon,

and this turns out to also be the angle of the shock.

(inverse sine of (8 inches / 96 inches)). The rubber bushings

in the shock can easily comply without transferring

excessive forces to the mounts. I'm sure Ridewell did this basic

calculation. If this were the cause then we'd be seeing similar

failures on the drive axles. The cause could be shocks that bottom

before bump stops (shocks too long), folks retracting their

HWH jacks w/o first airing up the suspension, folks raising the

front off the ground w/o first dumping air, or simply and inferior

Ridewell design. After year 2000 or so, I was informed by

the engineering staff at Ridewell that all their suspension systems

underwent finite element analysis and subsequent redesign;

consequently the LXi uses a different shock mount system than

the WB's. Could be that Ridewell addressed an inherent weakness.



David Brady

'02 LXi, NC







timvasqz wrote:

I think the crack was there from off-camber HWH jack parking in
the

past. looks like the temper of the weld proved a brittle spot that

under normal conditions would not have issue. Then the new shock

absorbed more bounce but reacted equally agressive causing much more

stress on the mount. I think the mount post should have less strength

and be a point that can bend at failure. the tripod gussettes are a

bad idea.



I think problems arise when the bus air bags are dropped to be

leveled but the spot is too off camber. the HWH push one side up

and tilt the axle too much. at that point raising the front is

effortless and and the 30 foot lever post all the stress on the

tucked tire.



If I was to repair that mount I would remove two bolts and make a

trapazoid shape cut and replace the plate with a butt weld then build

the post mount back no better than before.



If you lose an airline and must drive. there is a screw set in the

maxicam to turn off the parking brake. you can then plug the airline

and fold it over then tape it.

Greg ofTim&Greg

94ptca



..--- In "WanderlodgeForum%40yahoogroups.com",
"Don Bradner"

...> wrote:

>

> I'm the latest victim of a driver's side front shock mount
failure.

It took out the brake line when it went. I was not far from home on

the way back from Q, so I limped on in (I know, in retrospect it was

too dangerous, but I kept a lonnnng following distance!)

>

> I've used the local Detroit dealer in Arcata (Trinity Diesel) a

couple of times now for service, so I called them, and the service

manager said he would swing by for a look, no charge. He ended up

removing the shock and the air line, and said that he would come by

the next time he was this way with a new airline. A new shock will

have to be ordered (the top bent/caved in) and they will schedule an

appointment to get it welded after they have that. Shock was 17

months old.

>

>

> Don Bradner

> 90 PT40 "Blue Thunder"

> My location: www.bbirdmaps.com/user2.cfm?user=1

>

No virus found in this incoming message.

Checked by AVG. Version: 7.5.552 / Virus Database: 270.10.23/1952 - Release Date: 2/13/2009 6:29 PM