A/C Rooftop Vent Cap

Nomad

Ok Verna, I won't :-)

Mr_Mrs_Gnome

@jkjenn, I bet they'd loan you one at the TL General Store. If not, do I need to throw one in my truck when we head that way??

Mr_Mrs_Gnome

Has anyone tried that Bondic (UV light activated) glue?

DurangoTaB

I think my dentist uses it ;-)

jkjenn

Mr_Mrs_Gnome said:

@jkjenn, I bet they'd loan you one at the TL General Store. If not, do I need to throw one in my truck when we head that way??

Good idea! I figured out another way. I pulled the Grand Cherokee up next to the T@b with the side mirror folded in, raised the air suspension sion all of the way up, and leaned up and out of the window and snapped it back into place. Necessity, again, proving to be the mother of invention.

BrianZ

On our last trip, I must have encountered a small tree branch hanging over our driveway, because when I stopped to get gas a short distance from home when leaving for the campground, I noticed the roof vent cap was displaced & hanging off to one side.  Turns out the screw was firmly attached to its mounting stem and the stem was broken off at its base.  The only thing that saved it from falling off was the thermometer cable I had tied around that stem for our outdoor temperature sensor.  I was able to clip the cap back on to the mounting clips, where it survived the rest of the trip out & back.

I've ordered the replacement vent at Chan's link on the first page, but wondering what kind of adhesive/caulk to use between roof & new vent.  Any suggestions? 

I had also ordered some of the following plastic adhesive, thinking I could first try repairing the stem..
J-B Weld 50139 Plastic Bonder Body Panel Adhesive and Gap Filler Syringe - Black - 25 ml https://www.amazon.com/dp/B01IBOK7FE

I'm also wondering if it might be better to not use the screw, but instead rig up a tether to attach the cap to the base, so that in the even it gets pushed off again, at least it wouldn't break the stem or fly off & it could be snapped back on.

BrianZ

Well, if I don't get any suggestions on a sealant to use for a new vent, I will likely give this one a try..

3M Marine Adhesive Sealant Fast Cure 4000UV (05280) – UV Resistant Adhesive Sealant for Boats and RVs – White – 3 Ounces https://www.amazon.com/dp/B0000AY0ND

BrianZ

I proceeded with the repair option first & happy to report that the J-B Weld Plastic Bonder did a great job gluing the broken stem back on..

It is very sturdy, so I'll continue to use it, and save the new part for the next time.

I did, however, implement the tether idea to prevent losing a cap..

Used the Dremel to drill a tiny hole in both cap & base for joining them by a two inch piece of 75-lb nylon monofilament.  I placed it at one side, to reduce the chances of it getting broken, since the cap is more likely to get pushed off from either front or back.  Guess I need to trim some trees too.

I melted the ends of the nylon string with a flame to make a small knob to prevent it from coming out.  I did the same for the original cap, for which I replaced the cap screw with a short & less secure one that should pop out instead of breaking the stem, otherwise I consider the screw optional with the tether in place.

Michigan_Mike

I like the J-B Weld product for plastic repair work as it sets up pretty quick and is solid as a rock.  The refrigerator handle on our 29’ Forest River trailer was Jerry-rigged on by the former owners and it was either buy a new handle or try to repair it and get some extra mileage on it.  When the plastic resin sets up it’s as good as new and extremely solid.  

Great product and is sold at Home Depot and most likely your local auto parts store.