[Charles]

It’s not even a question of Prevost standing up, it’s the inconvienience and the amount of time without a coach.

[Archived]

This is strictly an opinion unsupported by data.

I suspect there were adhesion issues that relate to the process or the materials selected that not only impact the delamination potential at the edges of panels, but as Fred points out affects the adhesion of the entire panel.

Robert Jones addressed the quality of the process in a response to a question saying in essence that the current materials and process is such that this delamination problem should be a thing of the past and the process has been in use for at least a couple of years now. Fred’s chassis is a 2007 so it is likely his coach was manufactured before the new solution to the problem was implemented and it is entirely possible other coaches might pop up with the same problem. Or not.

What appears to be unknown is why some coaches that date back to the start of XLII production have never had a problem, yet others much newer or among the first produced are affected. I think all anyone can do is pay attention to their coach and if the problem is detected, follow the procedure to get Prevost involved. They are stepping up to the plate so far and everyone that has had the repairs has seemed satisfied with the Prevost “goodwill”.

[Archived]

Tom,

Here I am confused again,,,,,, I thought you had a 2001 with rivets. How did you end up with delam issues?

Not trying to be nosey,, but if we trade up some day I would like to know as much as I can about this Delam issue.

Frankly, it just makes me sick that you guys are having such a serious issue with such an otherwise well built coach.

We converted an Eagle, raised the roof and smooth-sided the whole bus using 3M double sided tape and Sikaflex adhesive. Completed it in 1995 and my son is still driving it. So far no Delam issues, but it only weighs 26,000 lbs.

Maybe less flexing with the less weight.

Thanks

[Archived]

01 is an XL2 Robert, they were all glued.

[glen]

Looking to upgrade my 1991 Prevost with a Prevost., glad I didn’t drop the hammer earlier, Just got into my coach 3 years ago. How are things going with this problem. Are new (built) different and Prevost on top??

[Archived]

Glen,

Since the introduction of the H3 and the XLII coach skins have been bonded. The delam issue is almost non-existent on the H3 which came into being in the early 90’s.

The XLII which was a 2000 Prevost shell has had some issues. However the bottom line is Prevost has taken care of them with rare exception. The current fix has been to reseal the panels and then flush rivet the ends of the panels, the top and bottom, and apply surface strips to cover the rivets. You can read all about the process and the opinion of owners about the repairs on a thread here. The thread is lengthy and goes into great detail.

I think most will agree the delam issue is a concern in that if a coach has the issue it needs repairs, but I would not (and have not) allow the issue to deter me from buying an XLII or an H3.

[Archived]

It did and will deter me from buying an XLII.

[Archived]

And I said the same thing for a long time. I still believe the XL chassis represents a near bullet proof highly perfected design. It has some great features not available on the XLII, including very inexpensive glass replacement costs, the best fuel mileage, and no skin issues ever. But I have to vote for the XLII as being even better, all things considered and I voted with my pocketbook.

It is not only the improvements to the chassis that I like, but the conversion has also been significantly improved.

[Archived]

Don’t mind me Tom,,,, I get confused pretty easy reading too much into details.

I thought all the XL2’s were glued,,,,,,,,, just got confused by your coach description saying with rivets ?? Thought maybe you had one of the few with rivets.

[Archived]

Jon, way up near the top of this thread I see you posted that you ran a bead of sealant on the top strip. Between this and the window is a rubber seal, did you seal yours on the underside of the strip, the gap between the strip and the stainless panel?

I ask as we are getting into wet weather and want to maybe do this on mine.

And in case I am wrong, the whole issue with delamination is the ability of water to get behind the panels, correct?

[AL]

First I need to back up. My coach was repaired by Prevost just prior to the development and use of the current repair process. The repair process now used negates any concerns I would have regarding water intrusion behind the skin panels below the windows.

But since mine preceded that rivet repair process, despite the repairs I wanted to further insure my coach would not have future issues so I spoke to the Prevost technicians regarding the band that runs around the coach perimeter at the bottom of the windows, and above the stainless steel skins. The opinion was there is no downside to sealing that band along the top at the gap between the band and the skin. I am aware of the rubber seal, but by adding an RTV seal I am putting on a belt with my suspenders in that my sealing bead directs rain water coming down the upper sides of the coach to travel down the face of the band instead of any potential for it to work down behind the band and possibly behind the lower skins.

Because there is some concern about pressure washing having the potential to get behind the lower skins if the water is directed at the seams between the lower skin panels I also sealed all vertical joints using clear RTV also. I always hand wash my coach and never direct water at the seams between the skins, but I sealed those joints just to help prevent wanter intrusion.

[Corey]

IMHO…there is no question what-so-ever that the operators of pressure washers held close to the side panels on XL-II has been a factor in delam of joints.

1500 psi next to a seam has the power to start the loose panel process. Pressure washers are fine for pre wet, then rinse but at a safe distance as 3 plus feet away.

[Glenn]

Al, I agree pressure washer right on the seams probably not a good idea, and I am sure all the entertainers run the coaches through the truck wash where this happens all the time…have not had my bus at the Blue Beacon yet, still doing it by hand, but eventually probably will one day when I am on the road.

Jon, thanks for clarifying that, few more questions I hope you can clear up.

Did Prevost use to just insert sealant, like the Bostic 70-03 they use to seal the panels and make sure things were nice and tight?

This makes sense, because all of the coaches I see on here and elsewhere that have had the rivet repair (at least to me) seem to have only the edges of the panels riveted then covered with the strip. If this is the case, I would imagine that Prevost inserts sealant along the edges then rivets the panel.

Or do they completely remove the panel, re seal it with new adhesive then rivet the edges? It seems to me they are most concerned about delam along the panel ends? Not so much along the cross sections? Again issue being water getting in along the edges.

[Dean]

When Prevost repairs a coach using the rivet method, the process I saw was they loosen the panel to the extent necessary to insert the sealant / adhesive. That might require the loosening of the entire panel, or it might be limited to getting a small section of panel loose. Each situation is different.

What they do in all instances is reseal the entire periphery of the panels. Since most panels are adhering very well in the center, all that is required is to spring back a sufficient length of panel to reseal the perimeter and as far back as possible. It sounds simple, but the old sealer / adhesive has to be removed so the work is tedious and requires attention to detail

The two keys to the success of the current repairs is in the horizontal Z strip applied across the top of all panels, sealing completely against any chance moisture will migrate behind the panel. The Z strip and the top of the panel are both sealed and riveted.

The second reason for the success is the ends of the panels are resealed, then the panel ends are riveted to the frame, and then a decorative trim strip is sealed (bonded) over the joint between the panels and the rivets. That also eliminates The potential for moisture to get into the ends of the panels or behind the skin.

I do not know the brand or model number of the adhesive / sealant. I do know Prevost has used several different ones but I understand they now have one that has been completely successful.

Not all coaches that have some delamination or adhesive failures are redone using the rivet process. Several of our members have had their coach inspected and some of the coaches has a loose edge or some minor delamination. It has been my understanding that small area gets repaired. Some coaches have been inspected by Prevost and no issues were detected. The last word we got was the delam issue is a thing of the past because coaches produced after a certain date have no had any problems. It is also my understanding that entertainer shells with no stainless above the top of the bay doors have not had this problem.

[Archived]

When mine was done at Jax, the Tech told me they used Simpson 70-03. If that’s incorrect, John will likely read this and let me know.