Phil's descriptions and advice are excellent. Only thing I note different is the drain hoses for the rear drains in the far corners of the sunroof tray will go down the C pillar, not the B pillar. In sedans, Phil talks about the rear window vent drain tray. The sunroof rear drain hoses tee into the clear vinyl drain hoses from that window tray. They're quite accessible in the trunk. If you disconnect them at the tee it's a convenient place to use compressed air to reverse blow out debris blocking the tops of the drains in the sunroof tray or to push through a length of wire to ream it out (stranded copper wire can be stripped back a bit to make a flared brush on the end). In wagons, the drains go directly down to a slit opening on the back side of the lip under the rockers, and the same place the rear window drains go in sedans. The ends of the hoses are often visible in the slit and can be used to blow up compressed air, but not always visible. It's similar for the front drain hoses.

For diagrams, there are exploded views in the Haynes 240 Series manual on page 194. There are similar diagrams in the Chilton's manuals and I'm sure in others. Most just show a basic exploded view without enough detail to precisely identify how things like the seals go. I've incuded a basic Volvo exploded parts diagram for 240s below.

For more detailed adjustment procedures there's a good section in the old Gerhardt Volvo Problem Sover book (section 87-101), but it also doesn't discuss things like the seals. A scanned copy of the Problem Solver can be found online, but the sunroof article was unfortunately in an update package that was published later.

The 240 and 740 sunroofs are very similar. There is a considerable amount of information in the brickboard 700-900 FAQ here https://www.brickboard.com/FAQ/700-900/BodySunroof.htm

Note my comment there about the rubber wiper, a straight piece that goes across on a lip at the rear of the tray opening. It has an "h" shape profile. The tall part of the "h" goes toward the front of the car. I believe there is a similar strip on 240s. Tack the ends down with glue to keep it from lifting

There are also a number of YouTube videos that can be found on 240 sunroofs. Most are about dealing with the drains, but somewhere you're likely to find something that addresses things you're unsure of.

I like Phil's comment about rubber seals shrinking over time, especially in the harsh sun. When laying the rubber seal, push the rubber back to slightly compress it as you go to use a bit more of the rubber without causing it to buckle or pull away from the metal. If needed, you can try using a bit of RTV sealant to tack it to the metal. Where the two ends meet, you can tack the butt ends together with whatever glue you have that works really well on rubber, a 3M glue, one of the Gorilla glues, perhaps contact cement, hot melt glue stick (often one of my favourites) or RTV.

As Phil noted, the sunroof panel is not meant to have a perfect waterproof seal to the roof. The sunroof tray is meant to handle any water that gets past the seal. Except in the worst of torrential downpours, it should be able to cope even if the panel isn't sitting up nice and flush as long as the drain tubes are clear. Unfortunately, too many people don't make a habit of periodically inspecting and clearing the drains until they see water damage. Using a strong little LED flashlight in a darkened area can be helpful to see the rear corners or else just do as I do and blow them clear anyway. The Volvo parts diagrams show ring clamps holding the drain hoses to the spigots at the corners of the tray, so the drain hoses shouldn't be easy to accidentally disconnect during cleaning. I've found a length of decent diameter vinyl tubing can be used to suction debris from the back of the tray, taping the hose to a vacuum cleaner crevice tool.

More information than you probably need here, but I include it for the sake of others who might read this thread.



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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Hi,

I wish I could help you more, as I have a 1991 with a manual sliding roof.
Luckily it’s not having any problems as I do not care to use it much. I personally would not have purchased the option for the very reason you are siting.
The idea of a leakage sort of looms over your head.
It’s much like a rag top convertible’s fabric buffers up as air passes it’s vacuum over itself. It constantly reminds you how thin it is and it’s going to age.

I will say that since you are going to the efforts of redoing the roof you should keep things in perspective.
The sliding roof was never meant to be waterproof or seepage proof.
The seals only provide dust resistance and wind noise reduction from the air vacuum passing over it.
The air foil that pops up when open is also part of that system.

No matter how well you fit in those seals with the end’s butted together or use a tapered over lap.
It not uncommon to provide extra length on any replacement seals. Better to be too long than to short, as for wishing for more, is not a request at point.

All of these kind of materials usually shrink anyways. Be generous and don’t cheat in its placement before trimming.
The drippings, that Will seep by and end up underneath to the pan.
Sealing tight, just doesn’t matter, you just want the slider to move by smoothly.
You don’t want the nylon gear track to work any harder that necessary.
The track is very similar to electric antennas but they can get brittle as they age out over time from roof heat.
Antennas break from dirty or bent extension tubes along with rapid direction changes. I have realized it’s due to the radios power breaks, when rolling the ignition switch over to start the car and back.
I have put in a delay relay setup to minimize half the breakage issue. It’s a crude electromechanical setup but it works from parts found on the car in junkyards.
I’m studying on doing it electronically. At my age that stuff entertains me, as a final frontier.

Make sure the drain tubes are clear of any repair debris from the body work.
I think I remember seeing in some wrecking yards, that, there are four drain hoses coming from up there.they run down the A and B pillars and out on both sides of the car.
No matter which way it tilts, it can drain.
I could be wrong as it’s been a awful long time since I have seen these cars, with these sun roofs, in our yards.
If this is a sedan you will see some hoses in the trunk. Those only drain the rear windows venting area of condensation as air leaves the cabin. They come with all the cars, with or without, the roof mechanisms.

Do the best you can, as those engineers, had to do the same things too.

Phil