Over Cab Water Issue - HELP!

jakefromstatefarm · 02-14-2021, 09:04 PM

Hey everyone. I am the second owner of a 2018 Coachmen Leprechaun 230 CB Class C. This model has no slideouts, though I don't think its relevant.

We have some water in the over cab bunk area. This is my first Class C & my first experience with water. Looking for some opinions and some advice.

I discovered the water when a bunch of it dripped out by the pillar to the left of the drivers side windshield after parking it the other day - which was a day after a large storm. I removed the bunk padding, then a piece of 8 inch high, bunk width trim to reveal the insulation in the front of the cab. I removed the insulation. It was wet on the bottom, but not the top - leading me to believe it wasn't leaking in from the front window on the bunk area. I toweled up some standing water and then tarped it for a short rain that evening.

The next morning, I elevated the back of the rig and more water pooled to the front of that cab area. It was heaviest in corners and there was some evidence of staining there. As the water pooled, I used 3-4 dish rags to soak it all up. It took a while, as it would "refill" over 30 seconds, then towel dry, then refill, etc. When no more was apparent, I put in some paper towels (so I could tell later if they were wet). We did a quick overnight at the beach and remembered why we loved the coach.

Coming home from the trip, especially on certain downslopes, water would drip from middle center part of the bunk underside - just in front of the seam circled in green. It leads me to believe is is leaking out of seam? Does this seem right?

I've done a lot of reading and think I am going to clean and add fresh Dicor to the roof, then use Eternabond to tape up all Dicor spots and all roof edges. I will also strip existing caulk on other seams and add fresh Geocel Pro Flex caulk all around - and I am considering Eternabond taping those, too. I will also Eternabond tape the single seam UNDER the cab (viewable in photos, circled in green).

My questions really are:

1. Does anybody have opinions on where water entered? Roof and sides were not wet, but there was/is clearly water under the aluminum frame of the bunk (that pooled forward & that I cleaned up). I wonder if it was coming in via red circled area seems and dropping down sides. Another potential entrance spot would be from Dicor failure around the front corners where fiberglass cab connects with the roof. There is lots of Dicor there and it sometimes pools after a rain.

2. Looking at photo of rig, other than unsightly nature (and eventual resale impact), is there any reason you wouldn't recaulk and then Eternabond over the blue, green or yellow circled areas?
3. As I mentioned, water drops appear and drip on of the underside of the bunk, in front of the visible seam (circled in green) leading me to believe is is leaking out of seam? Does this seem right? And any idea how could I "free" the water that is in there? Is there any way I could safely drill to release it? Or some less invasive way? I have a fear water is trapped and I don't know how to get it out. While I have confidence in sealing from above, I don't have confidence in getting water out.

Any other thoughts, ideas, opinions, referrals to other threads, etc - are all welcome. Thanks!

PhilG · 02-14-2021, 09:42 PM

I had the same problems! Check the seals around the lights on the cab over and go with the Dicor and Eternabond on the the cab over. Your real problem is getting it dried-out and dealing with any mold issues.

Phil

jakefromstatefarm · 02-15-2021, 12:17 PM

@PhilG - When this happened to you: Did you ever locate the source of the leak? Or did you just reseal and tape and know you almost certainly closed it up?

Also, how did you dry it up? Wondering if I should:
A) Just air it out and add heat to aid evaporation, removing the easy panels that I can for air flow
B) Same as above, but buy a dehumidifier to dry it out
C) Same as above, but do a much more comprehensive interior disassembly - which will require me taking it in to a shop for that.

Thoughts?

PhilG · 02-15-2021, 12:53 PM

I discovered I had a leak when I removed one of the vinyl trim screws on the cab over that was rusting and water started streaming out. The only place I could find as a possible source other than the lights was an area where the cab over attaches to the roof at one of the corners. I parked the MH nose low, used dicor on the suspect area and then used Etrnabond on all the seams. I did as you mentioned - opened up the paneling as much as I could and kept the MH well ventilated. Others have mentioned using dehumidifiers and charcoal. I haven't seen any signs of mold or rot in six years.

jakefromstatefarm · 02-15-2021, 01:03 PM

@PhilG. Yes, we are in search of a dehumidifier now.

Can you tell me where the vinyl screw was you unscrewed? Was it on the one trim piece under the cab (circled in green)? I am trying to determine if there is a good “release” spot to get any remaining water in there out. I thought about those screws, but was worried those two sections could start to separate making things worse.

Glad to hear yours is doing fine after 6 years, btw!

Jake

PhilG · 02-15-2021, 01:33 PM

The screw I removed (rusted) was on the passanger side, outside ,forward corner-the green area in your pictures. I thought those screws would be short, maybe 1/2" long, but they're more like 1" plus. I'm not sure if they're structural,but I just left it out...

PhilG · 02-15-2021, 01:37 PM

The time of year and weather here in NC, probably helped to dry things out, it was late spring and warm, getting HOT for the next several months...

shortkid · 02-15-2021, 02:19 PM

On our first class c the window in the bunk area was not centered in the side wall. The hole was about an inch bigger than the window. When I took the trim off inside, I could see right out passed the sealant on the outside framework. I removed the window, cleaned the old putty off, installed new caulking and centered the window in the opening.

Iowaprism · 02-15-2021, 03:33 PM

We have a FR Prism similar to your overhead bunk on your unit. Two large trees deflected off each side of the cabover during the storm, tearing a small hole in the roof membrane. Insurance adjuster inspected the unit after a number of weeks when we could get one out to look at it, and when we took the trim off inside at the front, the insulation was wet, and the ADZEL wrap on the front had water embedded in the layers. No matter what I did with heaters and dehumidifiers, the water would not dry out of the ADZEL panel. They have replaced the cap and put a new roof on our unit. The water got in at the hole in the roof and the clearance lights that were not sealed well from the factory. We are still waiting to get it back from the repair shop as the last item to repair, the awning fabric, is backordered. With the weather we are having in Iowa right now, I hope they don't move it until it warms up. This is the first year since 2016 that the unit has been outside in the winter without a cover on it. Of course we have the second deepest snow pack ever recorded on top of it too!

craig111 · 02-15-2021, 06:33 PM

I had a leak in the ( trim) seam in the area you have marked in blue in your picture and water did show up in the same area as yours. I dried it out and used a hose on one section at a time until water showed up.

BDenn · 02-15-2021, 07:11 PM

I have a 2019 Coachmen MH. I could write a short story on how much sealing I did last year. The Place I would look at first for you would be your cab over plastic trim covering the screws that bend around the cab over You have part of it circled in blue. Last year at the end of the year we had big rain I was still on my mission to seal the MR. I drilled a 1/8 hole in the plastic trim under the cab over I was amazed how much water came out of passenger side. I used Flex Shot and started at the top of the plastic trim and pushed in a little in on both sides of trim and calked it wiped off excess. I did this on all of my screw cover trim. I might have made a mistake by using Flex Shot it contains silicon. Might have use clear Pro Flex.
I mentioned this on a blog and someone who had a Leprechaun and same problem said he had owned a class C Winnebago that had drain holes under cab over in the plastic trim he drilled drain holes in his Leprechaun.
Besides the upper lights this is where I would look. Check for water in the bottom of the plastic trim at the bottom marked in yellow behind the doors. Like I said I caulked mine will check next year for water. My front seam that is marked in green the caulking is cracking some like yours. Have not seen water there. If it in the inside It could drain there. I would consider taking off plastic cover in all areas and check screws for rust that might tell you of water entry. Keep us updated please I am interested for sure. I have heard of pressurizing using leaf blower or strong drying fan thru roof vent of MH and use soapy water and look for bubbles. I might try that.

BDenn · 02-15-2021, 07:32 PM

I was looking at your pictures. You have a front window. That could be a major leak. I sealed around all my windows. I would seal around outside of frame and inside by glass. would look there for leak.

Pathfinder75 · 02-16-2021, 03:03 PM

While my Leprechaun was a 2012 with same Azdel construction it did have Fiberglass cap so some of our construction is different.
COACHMAN Factory repaired mine in 2015. Another place to check is were roof changes pitch slightly (in your photo Red circle nearest the awning). I was told that was common and water tracked down internally forward to front of bunk. Was also told to drill 1/8" hole underneath near trim piece under bunk so it could drain.
Hope you can find you leak. I believe all those mentioned are possible. Noticed you Dicor at front roof edge looks like there could be cracked sealant there. The Eternabond may be the best option there.

jakefromstatefarm · 02-16-2021, 04:30 PM

Hey everybody - thanks for the thoughts so far!

@BDenn & @Pathfinder75 - You both drilled 1/8" holes to release water. I am wanting to do the same. Where exactly did you drill? Upload images if possible, but I am having a hard time tracking exactly where it was and what material.

@Pathfinder75 - Is the plastic trim the plastic molding that wraps around and covers the screws at seams?

Also - dehumidifier & as much easy DIY disassembly as possible to dry it out? Or take it in to a shop to evaluate? I think we got it fairly early - just wondering.

BDenn · 02-16-2021, 07:04 PM

Quote:

Originally Posted by jakefromstatefarm

Hey everybody - thanks for the thoughts so far!

@BDenn & @Pathfinder75 - You both drilled 1/8" holes to release water. I am wanting to do the same. Where exactly did you drill? Upload images if possible, but I am having a hard time tracking exactly where it was and what material.

@Pathfinder75 - Is the plastic trim the plastic molding that wraps around and covers the screws at seams?

Also - dehumidifier & as much easy DIY disassembly as possible to dry it out? Or take it in to a shop to evaluate? I think we got it fairly early - just wondering.

I was just inspecting for water intrusion. MH is put away for winter. I drilled my hole in the plastic screw cover just behind the seam that connects the front cap to the roof on the passenger side that is where I found water. I also drilled more holes for inspection. The Person who had a Leprechaun drilled 3 holes back where it curves behind the door. I sealed my holes after inspection. I also sealed the seams. I am paranode about water intrusion and trying to do everything possible to avoid it. Have seen to many Class C front bunk falling apart.

Pathfinder75 · 02-16-2021, 07:49 PM

Quote:

Originally Posted by jakefromstatefarm

2018 Coachmen Leprechaun 230 CB Class C.
We have some water in the over cab bunk area.

I discovered the water when a bunch of it dripped out by the pillar to the left of the drivers side windshield after parking it the other day - which was a day after a large storm. I removed the bunk padding, then a piece of 8 inch high, bunk width trim to reveal the insulation in the front of the cab. I removed the insulation. It was wet on the bottom, but not the top - leading me to believe it wasn't leaking in from the front window on the bunk area.

The next morning, I elevated the back of the rig and more water pooled to the front of that cab area. It was heaviest in corners and there was some evidence of staining there. As the water pooled, I used 3-4 dish rags to soak it all up. It took a while, as it would "refill" over 30 seconds, then towel dry, then refill, etc. When no more was apparent, I put in some paper towels (so I could tell later if they were wet). !

I agree with your dehumidifier process of drying out the structure. It does.sound like you caught this early

I attached photos of my front bunk trim removed.and another showing in that cavity. I BELIEVE THIS IS THE AREA YOU USED TOWELS TO REMOVE YOUR WATER IN THE DESCRIPTION QUOTE ABOVE.

I ALSO MARKED WITH TWO White X's about where I drilled two 1/8" holes to permit drainage.
I drilled from the bottom in front of the seam strip you circled in green on your under bunk photo. Any screws will be at that trim going into the bunk floor. So the holes should then be at the low spot about where MY White X's are

The idea being water should leak for you to see drips or running water coming down onto windshield. Also the water would drain versus soaking into the floor materials. The 1/8" hole is small so I do not believe bugs would ever be an issue. However once issue is solved you could always dab some clear silicone into hole to seal it. (This is how the Shop Foreman at Coachmen advised me prior to taking my Leprechaun to their plant for repair)
I see your in California so not a easy source for you but I must say working with Coachmen was a pleasure with exception of it being there for two months.

Best of luck. It really sounds like you got this under control just need to determine the leak source. I know this may be a challenge. Let us know what you learn when you feel you won this challange.
DAVE

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