Exhaust pipe for plumbing

[Devoman]

I am wanting to replace the seal on the top where the plumbing exhaust is.The sealant has finally gave out and is opening at the seems.
I was wondering if anyone knew what type of sealant this is.I can push it around and take it off with my fingers if I wanted to.It seems like it is some sort of plumbers type putty or maybe butyl.Any ideas.Thanks All.

[lewster]

Originally Posted by Devoman

I am wanting to replace the seal on the top where the plumbing exhaust is.The sealant has finally gave out and is opening at the seems.
I was wondering if anyone knew what type of sealant this is.I can push it around and take it off with my fingers if I wanted to.It seems like it is some sort of plumbers type putty or maybe butyl.Any ideas.Thanks All.

Devo,

If you want to make it totally 'bomb-proof'...........use SikaFlex 221. Comes in colors too. If you want to replace the original, it is Dicor self-levelling sealant.

Be sure to remove all or most of the existing sealant for the best bonding. If you use the Dicor, it seals very well to itself! I use tons of both, but most RV manufacturers use Dicor for most of their roof sealing requirements.

[Devoman]

Thanks Lew.

[JK3500]

Originally Posted by lewster

Devo,

If you want to make it totally 'bomb-proof'...........use SikaFlex 221. Comes in colors too. If you want to replace the original, it is Dicor self-levelling sealant.

Be sure to remove all or most of the existing sealant for the best bonding. If you use the Dicor, it seals very well to itself! I use tons of both, but most RV manufacturers use Dicor for most of their roof sealing requirements.

Lew,

I have the same issue with mine and am planning to replace with Ventline Galvanized vent covers. The covers did not come with gaskets and the RV shop where I bought them recommended installing with butyl tape, then sealing with self-leveling sealant. Any issues with this method, or would you recommend another? Thanks, jk

[Silverhobby]

The last ones I installed on my trailer, I used the butyl tape, a new rubber gasket, and sealed the screws with sealant. You should be fine with this repair.

[lewster]

Originally Posted by JK3500

Lew,

I have the same issue with mine and am planning to replace with Ventline Galvanized vent covers. The covers did not come with gaskets and the RV shop where I bought them recommended installing with butyl tape, then sealing with self-leveling sealant. Any issues with this method, or would you recommend another? Thanks, jk

jk,

That is the preferred method for installing just about everything on an RV roof with the exception of air conditioners: skylites, vents, fans, you name it. Butyl tape and Dicor self-levelling sealant around the seams and over the fasteners..........it's a winning combo.

[wahoonc]

Originally Posted by lewster

jk,

That is the preferred method for installing just about everything on an RV roof with the exception of air conditioners: skylites, vents, fans, you name it. Butyl tape and Dicor self-levelling sealant around the seams and over the fasteners..........it's a winning combo.

And pretty ugly...but that is IMHO

Aaron

[JK3500]

Originally Posted by lewster

jk,

That is the preferred method for installing just about everything on an RV roof with the exception of air conditioners: skylites, vents, fans, you name it. Butyl tape and Dicor self-levelling sealant around the seams and over the fasteners..........it's a winning combo.

Sounds great. Then that's what I'll do. Not too concerned with looks, as no one will really see it. As long as it works.

One question though, do I still need a gasket???

Thanks, jk

[lewster]

It can be nicely done with a little masking tape for a finished edge, and a slow, steady hand on the caulking gun. I would use a very tight fitting gasket over the vent if one is available.

[Devoman]

That is what I used.I cleaned the area up really good and used self leveling sealer like lew said to do.I also let it set for just a tiny bit and then layed another layer on top of it but it still has to be soft to stick together.I covered everything up.Even the screws.I am happy with the results.

[JK3500]

decided to use vulcem and keep it pretty. lathered it on pretty good on both sides of the gasket and dipped each screw in it before screwing in. if i find it leaks i can always go back and cover with dicor or sikaflex. think it turned out pretty good. the original gasket was pretty much shot. replaced with a new one and added a screen over the vent pipe.

(the plastic sheet is covering the fantastic fan hole while waiting for a repair and return from FF - but that is another thread...)

thanks all for your help. jk