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JIM KELLER
06-03-2008, 12:09 PM
Thought I would start a Thread under this heading for future research. Jon and others have entered important information under Ah, Nice Coach.

It is my understanding many XLII"s have had an adhesion problem for years before it is discovered. In fact, the problem is usually uncovered by Prevost Facilities rather than owners. The panels start leaking water behind the adhesion and runs out the bottom side. Sometimes water leaks or stains are discovered inside the Coach as evidence of the compromise. Although the Techs are willing to talk about the procedures and repairs, I think they have been instructed to not divulge information.

ajhaig
06-03-2008, 12:25 PM
While our "rivet" coach is for sale, someday we would like to get another coach. I view this XLII panel issue as a huge problem and sense that XLII owners somewhat downplay the issue.

We saw several XLII coaches at Prevost in Cal. & FL. being re-skinned. I was told the it was 300 hours in labor to remove the panels and install the new ones. Then add in the cost of the parts and paint, not cheap.

When I dropped our coach off at Panterra Coach I watched two guys re-skin the rear quarter of a "rivet" coach, I was amazed at how quickly they did it.

My longer term concern about these coaches is that as these coaches age will the adhesive issue become more widespread and at what point will Prevost no longer pick up the tab?

Many XLII entertainer coaches don't have the stainless panels, perhaps this is the way to go?

AJ

Ray Davis
06-03-2008, 12:57 PM
We saw several XLII coaches at Prevost in Cal. & FL. being re-skinned. I was told the it was 300 hours in labor to remove the panels and install the new ones. Then add in the cost of the parts and paint, not cheap

Although certainly not cheap, am I not correct in that Prevost is handling this as a warranty item for customers. And, I believe they are also giving an allowance to the customers to pay for polishing and repainting. It seems that Prevost is bearing the brunt of this issue, not the customer (in terms of $$)

Ray

rickdesilva
06-03-2008, 01:34 PM
I wonder if they have published some sort of a technical bulletin regarding diagnosis and repair. Generally manufacturers are reluctant to print this info because it gets into the public domain. Perhaps Prevost could make some sort of a policy statement for us.

Jon Wehrenberg
06-03-2008, 02:07 PM
I have several comments to make, none of which are worth much.

For decades aircraft have used bonded construction. Adhesive bonding has been used on military, commercial and general aviation applications. Planes see more temperature extremes, and thus more movement of the affected parts than a bus will ever see. Why is Prevost having issues? Did they try to re-invent the wheel?

The bonding problem could be for a variety of reasons, or even combinations of reasons. The wrong material could have been selected. The engineering could have been faulty and the surfaces to be bonded should not have been bonded, such as two surfaces or materials that expand at different rates as temperature rises. Or there could have been a faulty manufacturing process. Is there a vintage coach that Prevost used as a test mule running around out there with bonded side skins that has no bonding problems or did Prevost just stick what they thought was a good idea out into the market to allow owners to be part of a massive field test?

Do seated coach operators have a bonding problem on their XLII coaches? If not, why not. At one time the word on the street was Prevost had no problems except those caused by converters that used excessive heat polishing the coach skins, causing the bond to fail. If seated coach operators are having problems also the converters are not the cause of the problem.

Why isn't Prevost sharing with owners the techniques to detect bond failure? Yes this alerts the marketplace to a problem, but in today's world with the internet does Prevost really think this is a secret?

While the lack of rivets makes the exterior look great and eliminates the usual paint lifting around rivets, and eliminates the skin buckling between rivets has anybody considered the use of riveted panels as replacements for bonded panels? Unless Prevost had an accelerated test program involving thousands of heat up and cool down cycles to test the adhesive now being used I would only feel comfortable with mechanically fastening the skins to the frame. It will take a lot of drill bits to get holes into the frame (the skins can be prepunched), but once the skins are bonded and riveted you could call the repairs a permanent fix.

What happens to the insulation behind the bonded skin. I was always of the opinion that after the panels on the exterior are installed, the entire shell is subjected to a spray foam insulation application from the inside which would further bond the skin to the tubular frame. When the outer panels are removed does this rip apart the foam insulation, and if it does should the entire skin be assembled without rebonding the insulation?

What kind of record keeping is being done by Prevost QC to correlate the failure of the bond to a specific production period, to the age of the coach, to how the coach is used and stored, to where the coach is typically used? Wouldn't this pin point with some degree of accuracy which coaches may be susceptible to bonding problems and which may never have problems?

Will the repercussions of this problem affect how Prevost stands behind their customers on this and other problems. The cost to repair a single bus has to be enormous. At what point does the burden of the repairs shift from Prevost to the coach owner? I can envision where this issue takes real value from every single coach owner whether there is a bonding failure issue or not.

What happens to the buyer of a coach who is not a POG member and who does not read or participate in forums? Is that buyer totally screwed?

JIM KELLER
06-03-2008, 05:10 PM
Jon, Outstanding ! And this is why this Topic needed it's own Thread.

Kevin Erion
06-04-2008, 03:32 PM
When I found the 01 Marathon with bunks and looked at it to buy, I also checked each panel to verify if it had any that might be loose. I did find one that I felt would qualify as loose, I called Bill Jensen before the purchase to see what Prevost would be willing to do. He told me that I would have to take it to a Prevost center for inspection before he was willing to say anything but he did say that if a panel was loose, they would change them all. I belive the feeling with that is that why do them one at a time, it is more cost effective to just get it all done.
Prevost Mira Loma agreed that a panel was loose so we scheduled for the time needed to do them all. It is my opinion that the sika-flex glue that they originally used would get hard and brittle and the new style sika-flex stays more flexible and able to "give" with the expansion and contraction of the materials.
Is the bus as good as new, time will tell. Is Prevost going to stand behind every loose panel bus out there, time will tell, I have to wonder after 10 years from manufacture date how they will handle it, I hope the same way as now. Would I go thru the process again if I had to knowing what I know, I guess that depends on the bus conversion and if it is what you are looking for, this Marathon is what we wanted and they only made 4 of them. One of the 4 I passed on because it was so bad from the inside out that no amount of work would get it back to what I wanted, the other 2 had some different interior colors that would not work for us.
I know that there are some 05 shells that have a similar problem as the early shells, something to do with a shift change at the factory and the new crew that did the glue didn't clean the metals correctly and the bond did not stick. I guess it is also very important that both materials are cleaned with the correct solvents before the glue is applied.
I also understand that there are some Prevost factory slides that the roof of the slide needs more reinforcements so they have to remove the roof skin, add the additional bracing and reinstall the roof skin.
So all this information has to make you wonder if newer is better, in my opinion it is if the gains outweighed the down side. We had a 99 XL45 Marathon that was a great bus but I wanted the bunks for my girls and I also like the looks of the new shell with the awnings on the roof. We also enjoy the larger windows, it gives a feel that the inside is much larger. But all these nice things come with the trade off, I can only hope that now that the side skins have been replaced, they won't come loose in the future, time will tell and if they do, will they do it again? Will I want to go thru it again, I guess we will see!
These are my opinions and the information I described above is from my observations and are not quotes from Prevost, Prevost spent a lot of money to fix my bus. I am the 3rd owner and I could not ask for better customer service from the Company! I do have a different story to tell about the service center that did all the work!

rickdesilva
12-02-2008, 06:16 AM
I thought I would bump up this thread again to get some more info. I ran my coach from NJ to Florida a few weeks ago and noticed a few panels had a slight "bulge" in some areas, nothing extreme. Just a very slight "bulge" about 2x12 inches in the middle of the panel on the flat section between the creases . Nothing that I would suspect that there was a problem. Nothing seems to be loose nor do I have any water leakage. They probably have always been there but I never paid attention to them. Based on the discussion here, I thought I may have the beginning of the dreaded XLII panel adhesion problem, what should I be looking for?

Kevin Erion
12-02-2008, 09:19 AM
Rick,
I discovered mine by trying to lift the panel at each seam. I don't know of any way to try to check the panel in the middle area where they bond to the frame.

Jon Wehrenberg
12-02-2008, 09:43 AM
When I have checked for delamination on bonded products we produced we chose a suitable tool such as a wood handled screw driver and we thunked (that's a highly technical term) across the surface lightly.

If there is a break in the bond there will be a distinct difference in the resulting sound.

Rick can lightly tap on the areas that appear to have bulged and compare the noise to surrounding areas. If the bond has broken the noise will have a "tinny" sound instead of a dull thud. Hard to explain, but very obvious.

I think in the case of the XLII where there is no tell tale rivet line the guy doing the thunking will have to discern where the structural members are and try to develop an ear to the different sounds created by a skin with the foam insulation bonded to it between structural members, the skin bonded to the structure, and the skin that has delaminated from the structure or the foam if Prevost still foam insulates the coach after the skins are applied.

I wouldn't get as concerned about delamination from the foam as much as if the skin is separating from the structure.

Kevin Erion
12-02-2008, 10:56 AM
Jon,
I agree, I forgot I used my knuckle to knock on the inner area's that would have bond to the inner structure.
my bad!

Petervs
12-02-2008, 11:36 AM
Can someone clarify for me the following?

I was under the impression that the H3-45 coach and the new XLII both had composite side panels, and the XLII simply has thin stainless steel outer panels glued ( ok, bonded) to the outside over the composite. So these SS skins cover flat composite panels rather than attaching to a skeleton of frame members.

Anyone seen an XLII with the SS skins off?

Kevin Erion
12-02-2008, 11:52 AM
No, the SS skins have no composite behind them, they are bonded to the interior frame that makes up the shell. trust me, I had a first hand look at my bus with the skins off.

rbeecher
12-02-2008, 05:37 PM
Rick,

I will send you a PM on this if you want the latest.

Richard Beecher
02 Marathon XL II 45
96 VOGUE XL 40 For Sale

Ray Davis
12-02-2008, 06:30 PM
Richard,

Share that we all might learning about the latest! :)

rickdesilva
12-03-2008, 01:40 PM
I appreciate everyone's response, I dropped a line to Bill Jensen and Carl Boulet the Service Manager at the NJ Prevost facility that services my coach and the response was immediate. The bottom line is that they want to see the coach to see what is happening, I'll follow up as we progress along.

phorner
12-03-2008, 01:49 PM
A friend of mine with an XLII may be experiencing problems with panel adhesion. This bus is no older that an '06 I think.

I'll keep ya posted....

Jon Wehrenberg
12-03-2008, 02:42 PM
I really believe that this problem may be shaping up for Prevost as "The Perfect Storm".

Joe Cannarozzi
12-03-2008, 06:59 PM
What they need to do is install rivets on anything that currently is without and be done with it:D

Buses w/o rivets is like a day w/o sunshine;)

phorner
12-04-2008, 01:06 PM
I had a chance to talk to my friend some more and he says that 3 panels have to be "re-glued" on his bus, a 2007 (conversion model year) XL2.

So, it would appear that the panel adhesion problems span several production years.

I'll keep ya posted should any more info be available.

sawdust_128
12-04-2008, 03:06 PM
I don't know a whole lot about this issue. While I was at Liberty, Stuart over the summer, I saw them bubble test a number of coaches for leaking panels.

I didn't think about this much until I read this thread and ran into a Prevost Maintenance Bulletin (Mi97-24). It is an 8-page PDF which describes using the evaporator motor, powered by a 24v charger-battery combination to presurize the cabin enough to produce bubbles in a soapy solution applied to the outside of the coach.

Would this not be a fairly simple way to test for the adhesion problems or does the loss of adhesion not usually cause water and air infiltration?

I downloaded the pdf and if you want it, I can email it to you or you can go directly to the Prevost site for service publications. It is in the maintenance info section for the H3 VIP 1997 year. Apparently, they have a video cassette demo of this as well.

SUBJECT: WATER INFILTRATION IN H SERIES VEHICLES

Hope it helps.

lewpopp
12-04-2008, 09:29 PM
Dudty, it looks like they are looking for airleaks around the windows. What do I know?

sawdust_128
12-04-2008, 10:26 PM
Lew:

Here is what they were looking for:

"On the above-mentioned vehicles, some vehicle body sealing joints may be defective, leaks may also be present at windshield or rear cap lateral window level."

I wasn't saying that this was specific to any given model or year coach. I was pointing this out as a method that Prevost recommends/uses to find places where H3 coach body integrity is compromised. It appeared to me that Liberty was using this or a variant of this method on XL coaches while I was there. I saw the bubbling out from around the stainless steel panels in the side if the XL. Also saw the bubbling at the edge of the upper composite panels. They were going through and fixing these panel issues with both used and new inventory.

Apparently, Prevost has some concern about the issue as they recommend that this test be performed on a schedule:

"Note: We recommend that soapy water test be performed every 4 to 6 months."

This specifically applies to : H3-41, H3-45 and VIP-45 Vehicles Model Year: 1995 - 1998

For VIN#'s :From 2P9V33494S1011057 up to 2PCH33414W1012177 incl.

rickdesilva
12-21-2008, 08:47 PM
I'm a little late posting this. But, after a few emails with Bill Jensen he offered to send someone to checkout my coach in Florida. But we decided that when I get her home to NJ after the winter I'll have her checked her out at the Prevost Service Center. It doesn't appear that we have any real problems now so I figure I'll wait until I get her home.

Sid Tuls
12-21-2008, 09:07 PM
I'm a little late posting this. But, after a few emails with Bill Jensen he offered to send someone to checkout my coach in Florida. But we decided that when I get her home to NJ after the winter I'll have her checked her out at the Prevost Service Center. It doesn't appear that we have any real problems now so I figure I'll wait until I get her home.

Of coarse you won't have a problem it's a Thompson !!

utahcamera
02-08-2009, 01:33 AM
Is this seperation still and issue with 2008/2009 XLII? For that matter is there a 2009 Prevost shell yet?

rickdesilva
10-15-2009, 04:18 AM
Its been a while but here's an update. At the OKC rally we (myself and the Prevost team) determined that there is some delamination in the center portion of the panel due to a prior owner overheating the ss panels when they polished the coach. Although it doesn't appear to be that bad, on a few panels where the panel is both painted and polished stainless, only the stainless portion appears to have a problem and its only in the center of the panels and not on the ends. My coach sits in the Florida sun and expands and contracts all winter and I figure its best to tackle this problem at an early stage before I develop any water leaks. I don't know what the process will be, but I told Bill Jensen and the service manager Carl in NJ that I want to head off the problem sooner than later. The estimate to do the repair is $3700. Basically it appears that they reglue the affected panels and state that the paint on some panels may need to be touched up or refinished. I have been very satisfied with the NJ Prevost repair facility and have no doubt that the work will be completed well. I know Kevin had a reskin, I was wondering if anyone has had this repair done and how were the results.....or should I have the repair done at all.

Jon Wehrenberg
10-15-2009, 07:13 AM
This opinion has not been affected by any knowledge of facts so take it with a grain of salt.

Prevost has often attributed the problem of delamination to converters who are overzealous in polishing the stainless skin. If that is the case then parking a coach in the sun is also going to create a problem. Way back in another life I was responsible for product development and we used adhesives to assemble certain components. The problems associated with that method of joining parts cannot be overstated.

Doing adhesive bonding of components under highly controlled factory conditions is essential. I have a serious doubt that a field repair can even begin to approach the integrity of a factory bond. If I had to have some panel delamination repaired I would likely try to insure no moisture would get behind the panels as my primary goal and would not attempt to remove panels to cure a delamination in the center of a panel unless absolutely necessary.

This may seem like heresy but if the delamination is within a small area I would seriously consider locating the frame structure in that area and using a few strategically placed rivets to resecure the panel. The cost will involve only the time to locate the structural members, drill the necessary holes and install the rivets. Laugh all you want but consider just how bad it is going to get if in attempting to do other types of repairs a window gets damaged, your paint gets damaged or an entire stainless panel needs to be removed and replaced. It has already been established this repair is Rick's financial responsibility so despite the quote, this is a blank check repair.

tpr
10-15-2009, 07:00 PM
I have a 2006 XLII. Carl found delaminated panels on both my slides. New Jersey did the repair in three days, no damage to the paint and I haven't noticed any problems since.

Alek&Lucia
10-15-2009, 08:09 PM
Did you have to pay for it, or it was freebie from PREVOST ?

Alek

tpr
10-16-2009, 07:10 PM
New Jersey had to get approval for the repair from Prevost and they did but said if any paint work was needed I was responsible for that cost.

rickdesilva
10-23-2009, 07:32 AM
tpr
thanks for the post regarding side panels. I have all the confidence in Carl as he has serviced my coach for the last few years. How bad was your panel problem? Were they seperating or loose and did they remove the panel to repair it. My biggest fear is that I end up with panels that are scratched and chipped and then I have a paint problem. I assume that they covered your coach because of the year. Any info you could provide would be appreciated. Thanks

tpr
10-23-2009, 06:51 PM
Rick,
WhenI bought my coach in April I had no idea the panels were loose. I had it at prevost in New Jersey for oil changing and anything else they thought needed to be done when Carl came out and checked all the panels. He found just the slide panels loose, he showed me that you could pull them away from the coach with a finger nail. They took both panels completely off cleaned off the old adhesive and reglued and put the panels back on. Luckily the slide panels stop at the point where is breaks from the coach so there were no paint chips or scratches to worry about. The invoice read $2,208.90 but they didn't charge me as Prevost approved the repair. Like you said Carl is a great guy and so in Judy in service. John the manager went out of his way to make me happy with a repair to my 1996 a few years ago but that's another story.