Bodywork and Glass Insulation

Links

There are some good links here, in the Camping section of Club 80-90 Wiki Camping interior - rust/insulation

Particularly the ubiquitous Bulley-Hewlett link on insulating and heating a camper van Bulley-Hewlett article

Front seat box area

HarryMann: Front seat box/battery box ~ Rust-area and sound/heat insulating

The front seat boxes on the T25, directly above the front spring hanger/turret, consist of a simple sheet steel box, with the flat bottom panels having pressed 'fingers' for stiffening. The box steps down to the battery box behind. They have effectively zero heat insulation, and transmit lots of suspension and road-wheel noise, unless heavily undersealed. The flat bottom is hard to get to and don't think is normally undersealed for this reason, nor the forward or inside faces.

After 15~20 years, these boxes can be showing signs of surface rust underneath, or even be perforated. For some reason the off-side seems worse than nearside on the two I've dealt with, which obviously points at the battery, or its connections and earths possibly being a source. If you're dropping your springs and shockers out, this would be a good time to attack the bottom of the seat tray with a wire brush, partic. checking for seam rust at the far back welded lip (the top of the panel by the handbrake from inside). Though this can be done at any time, access slows you up a bit. Thoroughly dry out once any rust has been uncovered (hot air-gun on 'mild' heat), and treat with your fav rust treatment. This one here has also had a quick spray coat of Chassis Black over the top of a thick brushed coat of Rust Encapsulator.

File:N-s seatbox treated chs.jpg

Next up, once that's all done ~ Stopping that drumming, transmitted wheel noise and keeping your botty warm!

A big difference can be made to this thin panel, by insulating from the outside. I used 12mm foil covered cross-linked ethylene foam (super roll-up camping mat, eBay, about £5 for 2m x 0.6m), cutting it accurately to panel shapes, ensuring it goes right up to the edges. HD spray adhesive onto both surfaces, a couple of thin coats, more if you want to wait for each to tack, then the difficult bit, manoeuvering the insulation panel into place without getting it hung up on the glue in the wrong spot. Having allowed for the thickness and butted them against each other nicely, I finished off with ally foil tape (Screwfix), lapping all the egdes as well as I could. Being a Syncro, a lot of shutz will be flying around up there!

NB. I only did the back (inside most)panel, the top and the front, as the rear step down to the battery box was heavily undersealed without any obvious fractures/cavities. Underseal is a double-edged sword. Where it was not applied to a fully dry area, over seams, bolt heads etc cavities often form, and they are a rust hotspot. If you see it flaking at all, there will be much worse behind as moisture will get in and stay there, and welded/flanged seams particularly, suffer (e.g. in inner wing just in front of the front jacking point).

File:N-s seatbox insulation chs.jpg

Finally, I've started on the inside of the seatbox, using self-adhesive bitumastic sound-deadening. Being a skinflint I've just filled the pressed fingers (cannot find a reasonable cost source of this brilliant stuff). The correct way to use it is to warm it up in the oven, or use a heat-gun (gently), and form it across a large area of a panel, in this case right into the pressed shapes. Ideally, a further sound and heat benefit would be had by also then lining this box out with cross-linked foam, also stopping stored stuff rattling about in there. However, the foil covered one would be better from a fire-hazard point-of-view, though is thicker. Whatever you use, it should either be moisture-proof itself or encapsulated using an impervious barrier such as heavily taped thick polythene (see the Bulley-Hewlett link above).

File:N-s seatbox bitumastic chs.jpg