Sunroof Leaks Sealant Advice

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.

robinwelch1000

New Member
Posts
15
Hi All
The inevitable sun roof leak has appeared, can I ask everyone for some recommendations on sealants they may “successfully” have used in the past
Thanks for any help you offer - Robin
 
dow corning 761 i think it was, otherwise any decent quality silicone will do it, most important bit is how clean the area your sealing is.
personally I try to use silicone which is not an acid cure ( most use acetic acid) as I dont like acids near me bodywork, rain does enough damage
 
We had both of ours out in January, we used Sikaflex 221:

2 TUBES OF SIKAFLEX 221 BLACK POLYURETHANE SEALANT on eBay (end time 23-Mar-10 09:59:12 GMT)

Ordered and paid at 3pm one afternoon and it was there next morning!

One tube is more than enough to run a decent 6mm diameter bead round both sunroof flanges.

You must be religious with cleaning the joint faces, the old original tape just pulls off. We cleaned with water followed by Methylated Spirits.

While you are there, and assuming that you are doing the job properly with the headlining out, the 14 screws that hold the two halves of the sunroof together, leak water. We went to B&Q and got some 'drain tap washers', 4 to a pack for £0.98p and fitted them under the heads on both roofs, that was where our leak was.

You might also want to look at the roof bar mounts as well, they leak....

Peter
 
Sikaflex is the stuff i was looking at this, should I ever need it.

SIKAFLEX 521 UV RESISTANT LOW MODULUS SEALANT - Sikaflex® 521 UV is a multi-purpose, UV resistant, non sag, elastic one-component silane terminated polymer sealant.

Sikaflex® 521 UV is solvent and isocyanate free.

Cured properties show excellent resistance to cut, tears, aging and weathering. Sikaflex® 521 UV bonds well to a variety of substrates and is suitable for making permanent, high strength elastic seals. Compatible substrates include: wood, metals (particularly aluminum including anodized components), sheet steels (including phosphated chromated and zinc-plated components), metal primers and paint coatings, ceramic materials, plastic and glass.
 
I bought some sealant from my local aquatics shop. It's supposed to be for sealing fish tanks if they spring a leak and you don't need to drain the tank so was ideal for me as I didn't have to worry about trying to dry around my sunroof.All I did was seal it up and seems to be fine so far.
Cost me £20 but well worth it !
 
there was a thread similar to this a few months ago - it might be worth you checking out - I do seem to remember that sikaflex is great but it dont come off - might be a problem in the future if the sunroof packs up, but take the time to check out the older thread.
 
there was a thread similar to this a few months ago - it might be worth you checking out - I do seem to remember that sikaflex is great but it dont come off - might be a problem in the future if the sunroof packs up, but take the time to check out the older thread.

A good point but it depends on what Sikaflex product you are using, some as the 521 remain flexible but others will harden.
 
Where are you guys sealing? Between the body work and the plastic tray?

I did some work trying to solve my leak on the weekend but it hasn't rained again yet so I haven't been able to test it out - this will be the next step if it hasn't.
 
Where are you guys sealing? Between the body work and the plastic tray?

Yes, take the tray out completely, clean the two joint faces and then either put the sealant on the plastic flange of the upper part of the sunroof or on the roof, but it is easier on the sunroof flange.

They are a fairly close fit in the hole, so two of you guiding it is helpful. My front one dropped in square first try, the back one had to be persuaded with a gentle thump!

Don't forget the rubber washers on the 14 tray screws.

Just refitted the headlining and rear carpet today, nice to have the amenities again!

I cut across the rear carpet between the front of the slots for the 3rd row of seats, allows the carpet to be hinged up to allow access to the fuel pump cover, without taking all the trim out to get the carpet up.

Peter
 
When I purchased my Disco one of the big issues it had was leaking sunroofs, both of them would leak very badly, I removed both units and replaced the seals and used some RTV Silicone Sealant, superb stuff and very cheap at £2 per 300ml tube. Waterproof for glassing and heat resistant to 200c.

If anyone is interested the stuff i used is from http://www.sylmasta.com/acatalog/Silcone_Cartridge.html
 
How exactly do you get the whole sun roof unit out then?

Remove the headlining then....

Gently remove the two drain tubes per roof, I found that if you rotate the tube it will break the seal against the plastic corner piece pipe, which itself very fragile. Once you've broken the seal it will pull off. A hairdrier might help by warming it all up. Those corner pieces are not available as a spare, nor is the roof flange sealer tape that was originally used by LR.

Take off any electrics, then undo the 14 pan-head screws and the bottom piece drops away. The top has to come out upwards and will take a decent push all around the joint area to free it.

Just reinstated my headlining and rear carpets after 3 weeks with no leaks.

Got to pull the front carpet now and see if I have any other leaks up front.

Note my comments elsewhere about rubber washers under the heads of those 14 screwws, and the roof bar mountings leaking.

Peter
 
Last edited:
I can strongly recommend sikaflex 221,295 or 296 uv. I work building superyachts and use all of the above products, either general sealing/sticking with 221 or 295/296 to stick windows in with. As the boats withstand all sorts of conditions at sea, they are not going to leak with British rain, lol.
However sikaflex 206 primer is a must to prime with first. It's pricey stuff but once you used both properly no rain will ever get past.
I've used it to seal my front frame to roof and drains to tray on front of my disco and no water has got past. Shame that the land-rover sunroof glass seal doesn't stop the water seeping past in bad conditions.
After a recent downpour water got past the glass seal and sat on the bottom tray, and didn't drain away properly as car was parked nose up on a slope.
Result, water dripping from winder handle.
Cure will be to seal glass permanently to frame with sikaflex flex 296 uv this weekend and seal rear sunroof all-round at the sametime. The headlining is then being recovered never to get wet again.!!!
Hopefully, lol.
 
Was previously recommended hippo sealant as it is regularly used on boats to seal windows I have not used it but next time I may try it.
 
Last edited:
Back
Top