Roof Vent

Another of the Winnebago Eurovan issues. . .

Like many others I had issues with a broken roof vent. When I got it, the roof leaked like a sieve and the mounting points for the middle chair used to fill up with water. Inspection showed many issues. The hinges had rusted completly through in some places, so it didn’t shut at the front. The latch at the back was also repaired and so it didn’t shut at the back properly either.

First thing was to fix the hinges

At this point it was kind of usable, but still leaked, just at more managable level. It still had to be taped shut most of the time, which was a pain. Sometimes would start coming off driving, couldn’t open without removing etc. etc.

I hunted for a replacement. Tried everywhere to find something of the same footprint without luck. I had seen posts from others where they had fit larger, RV style hatches. I even had one delivered but returned it because it was a) really plasticy and flimsy (not that the original is sturdy) b) would add about 100mm which further limits what carparks I can get into.

There are things that are nice about the original vent. Its lightweight (I measured at 1.3kg with trim)and its low profile at about 20-25mm high.

Roll forward a year and I found a new contender. The Lewmar Low Profile marine hatch, size 20. This is roughly the same size, claims a 25mm height (which is only partly true as it doesn’t shut flat by design) and has a stated 2.3kg weight. It is much sturdier than the old one and has a 8mm thick acrylic top. I am sure you also hear the difference in sound transmission but perhaps I imagine it. It has a nice locking position partially open and then a friction hinge that holds it at any position (it goes a fully flat). It has a tinted glass so lets more light into the van (both a good and bad thing!)

Due to the thickness of the trim on the old one, the Lewmar actually presents more open area but its thinner, to such a degree that the bolt holes are not covered by the roof plastic, as such it takes an interface plate to mount it.

First was to take the old one out, much easier than I expected, gentle pull and out it came (remove internal trim first)

First created a temporary wooden interface plate out of scrap ply. It was basically the same size as the old vent with a cutout for the new. It allowed me to drill the 4 holes in the roof and do a test fit. It was a good idea as I decided it was too small, made it about a 10mm bigger on front and back to give a reasonable bonding surface. The original vent had only 10mm or so.

The final plate, constructed out of carbon fibre at the larger size. It is bolted on left and right and bonded all the way around to the PSA roof using Plexus MA310 structural adhesive. The vent is then stuck and bolted to the interface plate using Sikaflex.

My struts for holding the roof up are currently at 500N (112lbf) which work fine for opening the roof but still struggle at holding it open at the safety strap height.

2020 update, finally made an internal trim for it. Basically an interference fit and a carbon fibre plate as normal.