Repairing body caulk

I've been dewinterizing and sanitizing my MH's water system and HW tank the last week or so.  I noticed that a corner of the caulked edge of the exterior access panel to the HW heater is coming away from the side of the MH body.  That probably doesn't make any sense, so check out the photos below.  Do I need to remove the caulk around the entire panel, tighten up the loose screws (photo #2), and re-apply new caulk all around?  Or can I just fix that one corner?  Either way, how remove caulk without damaging the body itself (from hard scraping or chemicals)?  Can silicone caulk be used for this type of application?  I have a tube of self-leveling Dicor, but obviously that would not work on a vertical surface.  No place around my area sells any other Dicor products.  Any tips are appreciated!

If silicone caulk was what I had available, then that is what I would use.  It doesn't seem that big a job that you couldn't redo it later if you get a better material.

Will tightening those two screw pull that whole assembly back in?  Are they loose or stripped?

KodiakRV said:

Will tightening those two screw pull that whole assembly back in?  Are they loose or stripped?

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They don't appear stripped, but I haven't tried to tighten them down yet.  I'll give it a shot tomorrow.

Scotty

...Looks to me like there might be an underlying problem with the HW mounting bolts - not the two shown in the pix which hold the frame in place.  It looks like some undue force has allowed the framework to pull away from the coach body.  Make sure everything is tightened down the way it should be before filling any voids with caulk.  If the existing is silicone then any 'new' silicone will not adhere to it successfully.  That means scraping all the old stuff off and re-applying.  If it's a latex / rubber based caulk then you can caulk 'over the top' but I doubt it will look pretty. 

Wherever possible, I usually use masking tape around any areas where I don't want the caulk and  'tooling' it with a wet finger.  It saves on clean-up and also gives a nice straight edge.  Keep the tip of the caulk tube clean.  Wipe off the nozzle frequently to prevent unused caulk setting on the tip which can spoil and drag the bead. 

BT

Buddy Tott said:

If the existing is silicone then any 'new' silicone will not adhere to it successfully.  That means scraping all the old stuff off and re-applying.  If it's a latex / rubber based caulk then you can caulk 'over the top' but I doubt it will look pretty.

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How do I recognize which type of caulk is there now?

Scotty

Silicone is more stretchy, it acts and feels like rubber.  Latex will stretch but tends to stay at its stretched out length before breaking.  Scrape some off and pull it between your fingers, though that's not an absolute test because a few 'specialized' caulks, especially those used on MHs may be latex style but with a high silicone-like (tetrachloroethylene and thermoplastic rubber)  content. Silicone should not be painted over - doesn't hold paint well when applied.  Most latex caulks can be painted over.  If it's the original, I'm guessing it's a latex or similar based caulk. Just take off as much as you need to to get a good seal.  From the pics - probably just the one side will do it.

When re-caulking spend the $$$ an get a tube that is specifically made for RVs. - not usually found at Lowes or HD, more likely CW or similar.  I recently used some fairly expensive and reputable caulk specifically for vinyl siding (it was the best Lowes had to offer at the time) on a small leak in the skylight of my MH.  It seemed to work okay initially, filling cracks and voids etc, but dried out and became powdery after a few months...and the leak returned!  I applied some other stuff, (purchased from CW) and no further problems.  Though I did have to scrape away most of the previously applied gunk and wiped down with rubbing alcohol to provide a clean surface for adhesion. 

BT

Here's your fix:

http://www.dap.com/product_details.aspx?product_id=4

You can get it at Home Depot. Way cheaper than any RV dealer product, will last forever.

Just a guess at this point, but I suspect you've got some underlying support problem that allowed it to pull away like that. Maybe water damage to a wood frame member? If those bolts don't snug up nice and tightly, I'd remove the whole heater and find out what's wrong.

Any good exterior caulk should work, but the problem appears to be in the wall, not the caulk.  I'm afraid you will need to remove it to determine why it is separating.

King Kaulk is a blended (hybrid) caulk that works on most things. Butyl-based caulk (some times sold as gutter seal) is another good choice for exterior applications round metal fixtures.

I guess at this time I have to toss in my 2 cents worth. I will no longer use any DAP products period. My trailer started showing signs of caulk drying out and lifting the seal. I began to cut away the old and replaced the seams with a DAP latex product that says it could be painted after 24 hours. The job was unfinished, a couple of days later I took the trailer out for a weekend, it really rained hard. In the AM I got up and the seams were washed clean. After I got home I called DAP, the attendent told me that it takes 10 days for the product to form a full water tight bond. Nowhere on the label did it state a 10 day cure time was necessary.

Nelson

Since we are camping the next two weekends, I unfortunately don't have time for a complete repair right now... but I want to get the hole blocked to

Needing to paint the caulk is not an issue, since it's not painted now as my photos above show.  There is no Camping World (or other camping store) within 120 miles of me, and the nearest RV dealership only carries the self-leveling Dicor.  I bought it just to have, but obviously it won't work in this case.  So that's why I was hoping that white silicone caulk would suffice, or at least some other white product that can be purchased at any hardware store.  Decisions decisions.

I would not hesitate to use a good grade of exterior caulk, the type designed to seal around windows and doors. For this particular one I would even use silicone if need be. The only down side is that silicone has to be thoroughly cleaned off before applying anything else when you do the final repair. Mineral spirits or alcohol will do that easy enough, though.

Thanks Gary, that's what I was hoping.  Before I re-caulk this week, I'll clean out enough of the old stuff to hopefully see inside the gap and check the wallboard for water damage.  Maybe that will give me an idea of what will need to be done further down the road (both literally and figuratively). 

Personally I would not use silicone caulk.  Not only will it not stick to its self other caulks do not adhere will in areas where silicone has been used.

Cleaning silicone residue off fiberglass and metal is trivial. Porous surfaces like a rubber roof would be another matter, but this is a solid surface. But an acrylic, butyl  or other type of compound is a better choice if available.

I have never considered cleaning silicone  off anything to be trivial.  I is very difficult to get it cleaned off most anything to the point that it can't cause problems.  Just ask any professional painter.

I have to agree with Ron.  Having used many dozens of caulks and caulking products over the years and cleaned off just as many, silicone can be a bear to remove.  The only times it is easy is when it has been applied over 'old' silicone or when the surface was wet, greasy or dirty.  If it comes off easily then it wasn't the correct application to begin with.  I recently stripped down my shower stall, taking everything to pieces.  Some previous owner had applied both silicone and latex caulks to everything - with a spoon, I think!    It took me three days to remove all the caulk but the good news was,  all the polished aluminum framework had been protected and looked like new (eventually).  Rule of thumb...use latex or water clean-up  caulk if the area is ever likely to be painted (even on the remote chance) and silicone based caulk if not (inside shower stalls, on tile-work, seams on countertops and around tubs etc).  Read the label on the tube.  If it says it is 'paintable' it is not true silicone.

There are chemical caulk removers on the market (which basically seem to be highly concentrated orange/citrus oil) which work reasonably well on latex caulks, but with silicone caulks they are not recommended and not that effective.  I use(d)  nylon scouring pads, a variety of self-made wooden/plastic scrapers (so as not to mark the underlying surface) and an abundance of elbow grease.

Scotty, if you intend to do a thorough job in the near future, and just want a temporary fix, use an inexpensive caulk,  one recommended for tubs that is also 'paintable' with a short curing time.    If it's It's going to be removed anyway, why make it hard for yourself or waste money?  Afterall, it's only temporarily.  The 'tub' caulk is a more water resilient than typical painters caulk, which is really designed to be painted over. 

Another caulking tip...for those of us that still live in stick-built homes with stucco finishes.  Use a 'sanded' tile grout (which comes in similar tubes as typical caulk) in a color to match the existing stucco, if available, around windows, door jambs and other cracks.  It doesn't shrink and does a really good job of filling the voids.  And because of the texture, blends in well with the existing stucco finish.  Readily available at Lowes and Home Depot in the tile section.  A little more expensive but worth the extra IMO.  It's also 'paintable' but allow for 24-48 hr. curing.

BT

Guys - it seems to me you are making this far too hard!  Scotty's question was not "what caulk is best?". He has limited access to materials and is asking if he can use what he has on hand for a short term repair. And he showed a picture of the surface - it is a metal panel against non-painted fiberglass. 

RV Roamer said:

Guys - it seems to me you are making this far too hard!   Scotty's question was not "what caulk is best?". He has limited access to materials and is asking if he can use what he has on hand for a short term repair. And he showed a picture of the surface - it is a metal panel against non-painted fiberglass. 

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True but don't want him to have to deal with problems when he make the repair later on.  Better to get a latex caulk for a temporary repair than to use silicone.  I know I would order something that was not silicone if I was in the same situation if I had to.

I appreciate you two arguing over little ol' me.    Latex is what I was looking for, the not-silicone sealant material.  If I can find that locally I'll use it, since it sounds like it would be easier to clean back off later.