cracked plastic around screw holes on a/c cover

[Pat]

I removed the a/c cover on the roof today to clean coils, remove a couple wasp nests and some spider webs,  and dust.  I notice the plastic around the each front screw hole had a crack radiating from the hole. I don't think the crack went all the way through.  Forgot to check the inside.  Is there some way to repair this with plastic or fiberglass?

--pat

 

[Tom]

If the cover is fiberglass (mine are), it can be fixed with either epoxy or JB Weld. Both will be a mis-match with existing color, but a small area of clear epoxy won't be noticeable from the ground. Since what you describe sounds like a stress crack from tightening the screws, a better fix might be to epoxy a washer to the cover at each of the screw holes.

 

[Bob Flight]

We have had the same problem with the old Coleman units.  We found that the cracks contined to grow due to the uplifting air movement around the units when driving.  Our solution was to add fender washers under the screws.  These are larger diameter washers with the same sized center hole, found at most hardware stores.

Robert Flight
Rochester, NY

 

[Gary RV_Wizard]

I'd use washers to spread the screw load across the surface around the hole, as suggested by Tom & Robert.  Fender washers (large solid washer) glued or epoxied to the cover would be the best.

 

[Don Jensen]

You should also stop drill the crack to prevent further movement.

Don

 

[Pat]

Washers it is.  Recommend slightly longer screws to accommodate the additional thickness of the washers? 

--pat

 

[Gary RV_Wizard]

Depends on the screws you now have.  Once a screw is long enough, extra length doesn't help and could even penetrate something you don't want.  The fender washer will add no more than 1/16 inch and screws generally come in 1/4 inch increments, so the next larger size may be overkill.