Cab Roof Lights leaking?? -- Need advice

[jim x 3]

My truck is an '88 F350 single cab with "Custom" interior trim - with a plain painted metal headliner for example.

As you may know we've been having a lot of rain in Northern CA recently. I find that water is leaking into the cab and wetting down the driver side seat belt retractor and coiled seat belt. (It was a surprise to get a wet shoulder when belting in). The interior of the cab appears dry, the water must be coming down the pillar between the interior steel panel and the exterior. And after driving the freeway for about 15 minutes, I noticed a slow drip drip drip sound coming from the front of the headliner although I could not localize the sound.

I suspect the seal between the cab roof lights and the metal roof. The lights appear to have a flat bottom that sits on a curved roof surface. Perhaps the gasket (if one exists) has given up and water is getting into the headliner space then running across and down the corner thereby wetting the seat belt.

Any other likely place that water may be intruding? Any thoughts on how to confirm and repair?

BTW, thanks to all of you for your advice in the past and Merry Christmas, Happy Holidays to you all.

Regards,

 

[OLDBULL8]

Need a pic of the lights. Most do have a rubber seal under them, but it's best to seal the hole thru the roof with RTV. The light's should have a drain hole in them, prolly plugged with mud.

 

[jim x 3]

As best I know, these are the stock lights.

 

[MIDNIGHT RIDER]

If they are factory-issue FORD cab-lights and as old as the truck, most likely, the lenses are full of cracks from fatigue.

Plus, the seal to the cab is probably suffering from age, as well.

Remove each light and clean the mounting surface of both light and cab.

Put a light bead of clear silicone (best) or black RTV around the perimeter of each light and a dab over each screw-hole.

Re-install the lights.

Now, take a bottle of CLEAR nail-polish and put several coats over each lens to seal all the tiny cracks.



After all this, you will probably find that the seal around the windshield is what is actually leaking.

 

[MIDNIGHT RIDER]

As best I know, these are the stock lights.

Those look like original Ford issue.

I got a brand-new set. identical in every way to the factory Ford ones, from J.C.Whitney to replace my old trail-worn ones.

 

[OLDBULL8]

Looks like those have the plastic base, if it is then they have a closed cell foam gasket under them. If the gasket didn't have a glue seal to roof, over time the plastic shrinks and they will leak.

 

[The Warden]

I would replace the bulbs with LED's (so that you hopefully wont have to ever remove the lens assemblies again) and then use your sealant of choice to seal the lens assemblies to the cab. RTV may work; so would pure silicone or gorilla snot (3M Weatherstrip Adhesive).

Can't hurt to also ensure that the lens assemblies themselves are intact and not cracked or anything on those lines. I had that problem; ended up needing to replace all of my lens assemblies.

Hope that helps some...good luck!

 

[Diesel_brad]

The foam gasket has most likely failed. But afterall it is 22 years old. I dont agree with siliconing the light back on. Just go to ford and buy 5 new lights. They are about $25(list) a piece or you can go the cheap route and just put gaskets in for about $5(list) a piece. If you silicone them on and there is a problem you will play hell getting the lights off and then you will have to SCRAPE the old silicone off to reseal it.

I would be looking for water leaks at the drip rail. The sealant is prob old and dried up allowing water to run right in. Grind or scrap it out and put some new seam sealer inits place

Just My .02

 

[h2odrx]

I thought mine were leaking it turns out to be the windshield