Upgrading the Leaking Tail Lights - the Saga Continues.

[FW28z]

I fixed my front clearance lights earlier this year. I replaced the incandescent bulbs with LEDs and silicone sealed them tight. Hopefully I'll never have to replace the LEDs.

I am not quite as concerned about using non-DoT approved lights for the clearance lights as I would the tail lights as in reality, they really provide no useful purpose that I can see.

[blw2]

unfortunately, I wouldn't think that silicone would be the end of it.

Now granted you would have done a better job and it might work in your case, but that is exactly the fix the dealer tried on my coach for the clearance lights, but it didn't work.... and really made a bigger mess for me because it took me hours to remove most of the silicone so that I could install the new fixtures that Thor sent me.... the original fixtures were ruined from the silicone.

Have I mentioned?..... I hate silicone caulk!

[FW28z]

[FW28z]

When I climbed up on my roof, this is how I found the front clearance lights. The dabs of sealant appear to have been factory applied, as it was on each of the lights. It wasn't silicone, but more like a polyureathane type sealant, similar to what I have seen used in the boat industry. It took a jackhammer to get the sealant off the screws (and some debonder).



There is a basic design flaw here, and anyone that understands how to roof or shingle a house knows you "overlap" the seams to prevent water intrusion, not "underlap" them. Essentially, the light fixture design creates a bathtub, and when coupled with the lame excuse they use for a gasket, they fill with water.

Even worse, there is no screw at the rear of the light fixture to hold the bezel down tight over the gasket. When I disassembled the fixtures, the gasket confirmed there was not sufficient contact in all areas.

Why these lights were not designed so that the white base fits UNDER the yellow lens is simply flabbergasting to me. I mean a bunch of 5th grade shop students could have designed a better fixture.

The only reason I can fathom is these fixtures may be specifically made for the RV industry, so they necessarily must be made to fail.

Perhaps it is an industry wide conspiracy to ensure RVs fall apart as rapidly as possible so that owners are forced to buy new ones, or at least keep the supply chain well funded with parts purchases.

I am coming to the realization that the lack of quality goes far beyond just the RV manufacturers themselves, but it is affecting the entire industry.

I know I am being cynical here, but come on RV industry, get it together. Don't do stupid stuff like this.

After cleaning up the lights, I threw the gaskets out and "bedded" the lights into a bead of silicone. I also bought new screws and put an o-ring under each one, as well as silicone.

Even though silicone is relatively easy to remove (in comparison to polyurethane sealants), I'll still probably have to blast them off if I ever need to change out a LED.

The trick though to silicone is that it is the most effective when under compression. For example, it seals better when it is sandwiched in between two surfaces like a gasket than simply applied to the outside surface.

[EA37TS]

Originally Posted by FW28z

When I climbed up on my roof, this is how I found the front clearance lights. The dabs of sealant appear to have been factory applied, as it was on each of the lights. It wasn't silicone, but more like a polyureathane type sealant, similar to what I have seen used in the boat industry. It took a jackhammer to get the sealant off the screws (and some debonder).



There is a basic design flaw here, and anyone that understands how to roof or shingle a house knows you "overlap" the seams to prevent water intrusion, not "underlap". Essentially, this creates a bathtub, and when coupled with the lame excuse for a gasket, they fill with water.

Why these lights were not designed so that the white base fits UNDER the yellow lens is simply flabbergasting to me. I mean a bunch of 5th grade shop students could have designed a better fixture.

The only reason I can fathom is these fixtures may be specifically made for the RV industry, so they necessarily must be made to fail.

Perhaps it is an industry wide conspiracy to ensure RVs fall apart as rapidly as possible so that owners are forced to buy new ones, or at least keep the supply chain well funded with parts purchases.

I am coming to the realization that the lack of quality goes far beyond just the RV manufacturers themselves, but it is affecting the entire industry.

I know I am being cynical here, but come on RV industry, get it together. Don't do stupid stuff like this.

After cleaning up the lights, I threw the gaskets out and "bedded" the lights into a bead of silicone. I also bought new screws and put an o-ring under each one, as well as silicone.

Even though silicone is relatively easy to remove (in comparison to polyurethane sealants), I'll still probably have to blast them off if I ever need to change out a LED.

The trick though to silicone is that it is the most effective when under compression. For example, it seals better when it is sandwiched in between two surfaces like a gasket than simply applied to the outside surface.

Unfortunately it is not just the RV industry. Those same clearance lights have been used in the trucking industry for ages. It has only been in the recent past where the manufacturers have gone to the flush mounted clearance lights.

[blw2]

thats the same lights i have.... but my sealant from the factory was some sort of clear-ish rubberized stuff. It actually seamed like great sealant over the screws.
But the gasket is what failed on mine too.

I searched for some different fixtures but never found a great solution. I was hoping for some sealed LED fixtures. Will likely get some like they put on ford or GM 3500 trucks some day.

[JamieGeek]

Here are the marker lights on our Axis:

Note a few things:

• The condensation in the middle one
• There appears to be no lip at the rear of them which would allow any accumulated water to escape

[FW28z]

I found some LEDs that matched the #67 bulbs pretty closely. Some bulbs might be a bit long to fit into the fixtures:




http://www.amazon.com/gp/product/B00...ilpage_o02_s00

I used some good quality 3M Marine grade silicone. You can see that I put a pretty good bead around the base of the light fixture. I also threw the foam gaskets out.




So far, no leaks...

[blw2]

well you might remember, teh dealer replaced my entire back wall because of the rot
I have been kicking myself since just after for not having them skip the factory routed in fixture...ugh...
anyway, they did a bangup job with silicone that actually looked like a fairly good seal. It DD hold for a long while. Noticed today that I have water in there again. No big surprise i suppose.
Tearing in, I see that teh housing is sealed with butyl tape so that actually looks like an intact seal and I was hesitant to break it. I'm pretty sure the silicone seal was still ok too. I feel like the leak was likely the circular white reverse lamp lens.

Anyway, I didn't dig all the way into the wood, but it was dry the best I could tell....
so I used some butyl as an attempt to seal the lens to the fixture, and more buytl to seal the reverse lens.

I'll keep an eye on it, but the fix I have in the back of my mind
for this, and for the over cab clearance lights
is to get some sheet FRP, or perhaps some UV resistant plastic, if I can find something..... much like the stuff the nose cap is made from I suppose....
and epoxy it to the surface to completely cover all cut-outs and holes....
and then use surface mounted fixtures.
but i'm hoping the butyl will seal it....

[blw2]

I was thinking more about this tail light issue this morning.

It has been bugging me for a long time that there seems to not be any sort of vent or drain in these fixtures. Maybe there is supposed to be one, but i haven't found it (not that I have gone over it with a microscope)
but if there was one, it would most likely be sealed up with the slop of silicone and butyl they put on...

I considered leaving a small length of the bottom edge un-sealed so that they can breath, and so that any water that does get in has a chance to get out. Every time I think of this I second guess the idea, thinking that while underway, rain might actually get shoved in from the air Eddy currents back there...

Anyway, I had a thought this morning.

The routed out recess for the fixture is let into the rear wall of the bedroom. It wouldn't take much at all to drill through the wall into the interior for a vent. Probably wouldn't serve well as a drain, since we don't want water inside, but as a vent perhaps, might help.
I was thinking a small hole, or perhaps something with a vent cover similar to this



i don't know, just a thought to throw out for opinions