Roof
OK so this is the area I looked at today. The images show the roof after the filler was removed to expose the old repairs.I had to get through a half inch wodge of filler on the frontmost section, the MIG welded one.
The second patch is interesting as it would seem that a pin or poke welder was used here, you can see the very small spot weld marks around the periphery of the patch. This type of welder is not generally found in a body shop it being more used in the aerospace industry.
Basically it is used for single side welding of very thin metals 24 SWG top panel being about its limit.This would explain the fairy rings found in the roof as seen in the PB images (currently off line) that I mistook for pulling studs.
https://goo.gl/photos/dZZczVSNtu82yrHz9
This is what I had mistaken for a piece of card it is in fact cut from a tin can and as you can see from the printing its Japanese. So this roof repair was almost certainly carried out before shipping, worrying! In the other image you can see clearly the fairy rings.
https://goo.gl/photos/u6mpu4BE3jp1aD659
This is the MIG patch at the top of the screen pillar, the one buried in filler, as it is being opened up.
I thought that this was the point where the screen pillar would be let in and I had expected to find corrosion around the over lap joddle. I believe this is not the connecting point at all as there appears to be a factory joddle further back and this brazed as you would expect to find.
Who ever carried out this repair, Nippon or UK, has welded the outer skin screen panel patch to the inner cant rail sub assembly and so blocked the run off for any moisture build up leading to the extensive corrosion in the surrounding area. I wonder if anyone out there can put up the panel exploded view for this area so I might confirm my suspicions?
After putting a camera down the offside there appears no connection between the sub assembly and screen pillar, although the gap is tiny.
If this is a connection point then it is a design flaw for the reasons stated earlier.
https://goo.gl/photos/74m7hY4y8Ab1PnLQ8
It might be a idea for other owners out there to treat this area if it has not already been done.
It is a simple strip out. You will probably be able to do it by easing down the headlining.
This is the area that needs the squirt. X marks the spot. If you have a probe then direct it rightward and that should allow enough jollop to roll in behind the screen flange at this point. The sub assembly masks the rest of the screen flange. I will have a look and see of there is somewhere that will allow access to that bit later.
https://goo.gl/photos/CstSWBv4XJZ4Nu5T9
In these pics you can see the sub assembly from outside under the roof skin and inside the van, dunno if tin tops are the same, that reinforces the roof. The roof outer is just a skin and will have little to do with the overall roof strength.
The corrosion that occurs on the roof panel outer skin is caused by corrosion occurring in that sub assembly and "leaking" through to the thin outer skin. It is not a break down in the guttering sealant as I first thought.
The roof skin attaches to the flange of the sub assy and thats where the corrosion starts.Certainly on this Bongo the outer skin rusting is fairly local to the cross rails and the factory joint. but a good squirt in that sub assembly boxing would not go amiss.
https://goo.gl/photos/NpAyEB6vD8gpvLcU6
This image is taken inside the sub assy.
https://goo.gl/photos/51A6bi8BLots3ZuB8
These images show the area of the MIG patch after cutting out, dressing and Fertan-ing ready for patching and the corrosion caused to the screen pillar by the botched repair.
In the pic of the lower end of the screen pillar you can see two holes drilled to allow treating from that end, these will be plugged with grommets before refitting the wings.
Just to point out the brace panel by the hinges, you can see very poor workmanship here the edges of the panel have been undercut by the welder and these will need to be put right along with three MIG plugs on the inside. These I think are where the mig balls came from. I can find no evidence of accident damage on this side. I suspect it was replaced because of corrosion when the up dated front was fitted. Th repairer of this side was definitely not the same as the other!
https://goo.gl/photos/GqrPX2tFr5nLQSzk8
Right that bit out of the way.
I am going to get away from the Bongo for the weekend while the Fertan works its magic.
Dungeness RSPB is calling me so thought I would take a break in another Bongo!
P.S.
I intend to fit a wind out awning to the van and wondered if anyone out there has any images of the rear of a Fiamma awning?
I would like to fit the awning directly to the roof rather than using gutter clips and would be interested as to how it mounts.
Thanks.
I hope that lot came out OK.
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