MaxxFan Install at Rear of 170

atulin

atulin

New member
I'm on a posting streak tonight so here is my MaxxFan install from about a year ago. I wanted it at the back for maximum cooling from air coming in the front windows or dash but the roof ribs in this area present a bit of a challenge. Here is how I decided to deal with that. I don't think I've seen anyone post about doing it this way and it hasn't leaked in the last year so here you go. (also, I did disassemble the fan and paint the parts that are visible from the outside black.)

fan-1.jpg

fan-2.jpg

fan-3.jpg

fan-4.jpg

fan-5.jpg
 
Hooligan

Hooligan

ok
neat idea. I was thinking of welding in a little patch in after cutting the rib out but now I think I'll leave it like you did with the patch.
 
pfflyer

pfflyer

Well-known member
Copied this idea and leak free for 3 or 4 months now. Don't remember and cant tell by the pictures if you used alum flat stock on top of the flange but I copied that idea as well from someone.
 
Last edited:
pfflyer

pfflyer

Well-known member
Not sure what it is called (butyl rubber I think) but Maxair directions will tell you. I'm sure Fantastic fan's directions will also name it. Most RV places carry it or should be able to find it on line as well
 
2

220629

Well-known member
jhastings000 said:
Thanks for the write up, esp. for waiting a year before posting to make sure it didn't leak!!!

John
Click to expand...
I used a more crude, but basically similar installation method in 2008. It was leak free until this year. The rib seal method is still fine. The plastic flange cracked. I used Eternabond tape to reseal. My next van and vent will have a metal flange.

Some details on my more crude installation are here.

https://sprinter-source.com/forums/showthread.php?p=37473#post37473

vic
 
G

Graphite Dave

Dave Orton
Aqua Puttana said:
I used a more crude, but basically similar installation method in 2008. It was leak free until this year. The rib seal method is still fine. The plastic flange cracked. I used Eternabond tape to reseal. My next van and vent will have a metal flange.

Some details on my more crude installation are here.

https://sprinter-source.com/forums/showthread.php?p=37473#post37473

vic
Click to expand...
I was told by a RV service shop that the plastic flange will eventually break. That was why I added the 1/8" x 1" aluminum strips between the bolt heads and the plastic flange. Got rid of the point load.

https://sprinter-source.com/forums/showpost.php?p=129813&postcount=1
 
2

220629

Well-known member
Graphite Dave said:
I was told by a RV service shop that the plastic flange will eventually break. That was why I added the 1/8" x 1" aluminum strips between the bolt heads and the plastic flange. Got rid of the point load.

https://sprinter-source.com/forums/showpost.php?p=129813&postcount=1
Click to expand...
Yes. I wouldn't disagree that stresses take their toll on a plastic vent flange. That is why I wasn't really thrilled with the flange material/design, but that was how the constantly vented unit came and I liked that constant feature. The constant vent has worked well for my use.

From the beginning my fallback for any leak repair was to use Eternabond tape. The Eternabond tape can cover a bunch of sins. So far it has answered my plastic flange leak issue with little repair installation effort. Time will tell.

vic
 
Last edited:
B

Bbgq

New member
Like others I was challenged by how to install a Maxxfan over a rib. I have a 170 and my goal was to position the fan over the middle of the platform bed. This location has a roof corrugation in the way and traversed a roof seam. Not to be detoured I proceeded.

After some thought I decided to notch the rib rather than use a spacer under the frame. Using additional aluminum flat bar I built up a vertical surface to butt up against the open end of the rib. To seal the top of the rib I left a 1” tab cut from a piece of 2” flat bar. This created a nice cavity surrounding the entire notch which I packed with butyl tape caulk. See photos.

In the end, the thickness of the plastic frame flange plus the 1/8” flat bar with a thin cover of butyl caulk between layers provided the right thickness and height for the vertical surface to reach just above the top of the rib. This allowed the tab to protrude over the top of the rib with room for caulk underneath.

The seam wasn’t any problem except I used a little extra caulk to fill the void on the roof top and notched the plywood backing frame underneath. A plastic kitchen spatula worked nicely for trimming the excess caulk.

I also followed a marine industry tip and counter sunk the plastic flange screw holes. The beveled notch creates a space for caulk and eliminates the mounting screws from becoming a leak path. After inserting the screws thru the flat bar I wrapped a small strand of butyl caulk around the threads just under the bar. When the bar is drawn against the plastic flange the caulk fills the void. In order to maximize the seal it is important to tighten the fastener with the nut while holding the screw still.
Bill
 

Attachments

alexk243

alexk243

KulAdventure
pfflyer said:
Not sure what it is called (butyl rubber I think) but Maxair directions will tell you. I'm sure Fantastic fan's directions will also name it. Most RV places carry it or should be able to find it on line as well
Click to expand...
What size tape did you use? What sealer are you using in the caulk gun?

I am assuming it is some sort of self-leveling sealer, but I cant seem to find any sealer that is black... and my roof is black like yours
 
Last edited:
pfflyer

pfflyer

Well-known member
alexk243 said:
What size tape did you use? What sealer are you using in the caulk gun?

I am assuming it is some sort of self-leveling sealer, but I cant seem to find any sealer that is black... and my roof is black like yours
Click to expand...
The butyl rubber tape comes in rolls and it was about 1or 1-1/2" wide. Search on Amazon for butyl tape or any RV supply would have it. I am not the original poster of this thread and my van is silver. I used Dicor 501___ grey self leveling lap sealant in a caulking gun.
 
Last edited:
hein

hein

Van Guru
alexk243 said:
How does that adapter work with the odd shape of the ceiling in the vans?

It's designed and CNC machined to fit the contour (ribs and curvature) of the roof and provide a flat surface for the vent flange. We have adapters for the standard fore and aft locations but can also do offset and custom locations. When offset, the adapter allows the fan to sit level which looks better. The interior bezel is harder to fit so there is a trade off.

Click to expand...
 
Last edited:
alexk243

alexk243

KulAdventure
Sorry, looking at the ebay picture it looks a lot different from the one you just posted. The ebay one does not look like it has a spot for the ribs like the picture you posted did. Are they the same?
 
You must log in or register to reply here.

Top Bottom