Leaking Marker Lights

[Outnabout]

I am getting water in the cab overhang, right beneath the marker lights. The water seems to be coming in where the wires penetrate the aluminum. I taped up the lights on one side to try and isolate the problem which seemed to work but this morning had a small amount underneath the driver’s side light which I didn’t tape.

Should the entire light assembly be removed and somehow sealed or do people put a caulking bead around the assembly while still attached.

What material is best? I’ve read Dicor, some kind of 3M product and butyl tape.

What are your experiences? Thanks.

 

[longhorn1]

Had a suspect marker. I removed the light and cleaned the aluminum. I put sealant into the wire hole and screw holes. I then put a circle of sealant around the hole and screw holes. I painted the screws with rust paint and firmly pushed the light back into place and re-installed the screws. I used silicone as it is hidden. I intend on doing the others. You should replace the galvanized screws with matching stainless steel. The two I removed we're rusted and I believe due being incompatible with the aluminum. This will be a summer job.

 

[inciter]

If FWC is using Galvanized screws with an aluminum body and frame system there is a problem. One would hope they are taking the necessary precautions to prevent long term corrosion. With the 2017+ F trucks being all aluminium bodies it's not a good mix in my opinion. Interesting

 

[Outnabout]

Had a suspect marker. I removed the light and cleaned the aluminum. I put sealant into the wire hole and screw holes. I then put a circle of sealant around the hole and screw holes. I painted the screws with rust paint and firmly pushed the light back into place and re-installed the screws. I used silicone as it is hidden. I intend on doing the others. You should replace the galvanized screws with matching stainless steel. The two I removed we're rusted and I believe due being incompatible with the aluminum. This will be a summer job.

Do you recall the screw size? I’d like to get some before I start removing lights.
Thanks