| Author | Message | ||
| Jim Stewart (H3jim)
Rating: N/A |
I'm getting to the point where I need to install my vent pipe from the holding tanks. My dumb question is "How did everyone seal their vent pipe?" My thought was to cut the hole, and get a flashing from home depot and just silicone it. Am I missing anything? I seem to remember someone posted that they cut the hole very close to the size of the pipe, then cut one of those rubber couplings in half and used half on top and half on the bottom. this would also tie it together mechanically. I'm not sure how that would seal, or how the rubber would hold up to years of sun. Any other ideas? | ||
| Marc Bourget Rating: N/A |
Jim, Were you planning to use one of those aero or venturi caps for the waste vent? I haven't investigated them closely since I'm not "there" yet. Maybe the sealing process on the cap would work. Now that you've brought this to my attention, without the cap and a simple tube through the roof, I'm thinking of either a bulkhead grommet or a triangular rubber gasket and hand forming an aluminum compression ring that would press the gasket against the pipe while also protecting the rubber from UV exposure. Black rubber usually tolerates UV pretty well, but the ring would really take care of the problem. Since I'll be figuring a way to exhaust the fumes to lower the pressure in the waste tank while "exercising" the toilet, I'm thinking that my exposure above the roof will be minimized, maintaining, as much as possible, the standard, sleek, roof profile without the "garbage" that clutters many conversion roofs. No, I'm not passing out insults, just stating a personal preference in a mildly sarcastic way. The roof top "clutter" is perfectly fine, since that is "your way" Onward and Upward Marc Bourget | ||
| Ed Jewett (Kristinsgrandpa)
Rating: N/A |
Check the archives,(may have been on another board) one person said that he piped his into the engine compartment and another said he piped his into the air intake for the engine. Kinda like propane injection. I'm going to try to tig weld a sleeve and use a mushroom cap. It will have to be fastened/re-inforced to make sure low limbs and phone lines don't tear the coach roof skin, but that is a minor problem. Ed | ||
| TWODOGS (Twodogs)
Rating: N/A |
all it has to be is 1/2 inch above the roofline...no cap needed..so what if it rains in your black tank...clear silicone has a good lifetime exposed to the sun...mine ...is the one piped into the engine compartment...no smells...no holes in the roof... | ||
| Gary McFarland (Gearheadgary)
Rating: N/A |
What about the "Open straw" theory posted in another thread? Theoretically if you went fast enough you would suck all the s#it out of the tank. that would mean you'd have to limit yourself to 500mph or so...very restrictive. LOL. Sorry guys, just venting. (Aw, Geez, did I say that?) Gary (I'm gonna go out and work on my bus now) | ||
| TWODOGS (Twodogs)
Rating: N/A |
that's what ya' call .....NO S**T | ||
| Jim Stewart (H3jim)
Rating: N/A |
Punster, good one Gary... Or my coach really sucks over 500 mph... Clean lines are better, but is the juice worth the squeeze? My coach is tall and flat topped, so not much is visible, especially if it doesn't stick up too high. I really don't want to take up any more interior room by running pipes inside the living space. Also to run pipes around and through to the engine area, when my bath area is fairly far forward, also seems like a lot of extra effort, wasted space and probably is not possible to keep the pipe always going up and not down (making a trap). Its only a hole that can be sealed - although I do not like the idea of putting a hole in a perfectly good roof. Its also on the drivers side, further away from trees, probably not too visible, and I will have air-conditinoing units and awnings and maybe a deck and solar up there anyway. Marc, I might use one of those vent venturi's, but only if it proves I need to. | ||
| Ed
Rating: N/A |
I am using a shower drain on the flat part of the roof. Good seal with caulk and the compression fitting and does not stick up. | ||
| Henry R. Bergman, Jr. (Henryofcj)
Rating: N/A |
Ed...that is a gassy idea piping the black tank vent into the intake of the main warp engine. I mean....the worse you eat, the faster your coach will go. Kinda like something fur nothing?  | ||
| ChuckMC9 (Chucks)
Rating: N/A |
I'm also venting into engine. See here for more than you'd want to know. | ||
| Jim Stewart (H3jim)
Rating: N/A |
wow Ed, great idea! | ||
| Lin Rating: N/A |
I like to keep things simple. Standard RV roof vents are low profile and not particularly unsightly. We used the base of one of those and just have a PVC tee on top to do the ventury thing on the road. Since the roof is covered with a Kool Seal type of stuff, there is no possibility of leaks. | ||
| David Dulmage (Daved)
Rating: N/A |
I used a large rubber grommet intended for connecting waste pipes to holding tanks. This made a very good seal where the pipe went through the roof. I installed the standard RV vent flange and cap assembly which was large enough at the base to clear the grommet and sealed this with caulking. No leaks so far. Dave Dulmage (MC-8) | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
I'm da one that got a flexible pipe coupling and cut it in half, stuck one half inside and the other half outside, clamped them down with the hose clamps that came with them, and gukked some silicone inbetween. It's worked famously for three years now.... | ||
| Jayrjay Rating: N/A |
You cut a hole in your roof... sooner or later it's gonna' leak. Mine (and many other folks) is run out into the left rear wheel well, engine compartment etc. The original plumbing in the bus had the vent tapped into the air intake for the engine, just ahead of the breather. Remember that the only time you have gas/air flow out of the vent is when you run water or flush the commode. I've never smelled it, nor has anyone at the many camps I've stayed at had a comment about it. Cheers...JJ | ||
| Don/TX
Rating: N/A |
I agree Jayrjay, I ran mine into the right wheelwell, with the intent of hooking into the intake system someday if I needed to, or going up if needed. It never smelled, or caused any problems there, so I left it for years. Parked close for 6 months at a time in campgrounds, NEVER did it create a smell | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
. | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
PS, I cut the outside of the pipe at a little angle so it acts as a venturi that sucks on the tank when underway. That way when you're driving and the wife uses the pottie, the cabin doesn't get stunk out! Here: http://www.heartmagic.com/00ventstuff.jpg | ||
| mclough Rating: N/A |
i met a man a few weeks ago that invented a new device for buses. its a unit that pumps the black tank waste up to a roof unit that treats and heats then send it to engine to be exhausted out with buses exhaust. NEVER dump a tank again. gives new meaning to "up in smoke" morgan | ||
| Larry Bennet (Eurof3)
Rating: N/A |
Gotta agree the less holes in the top the better. But you only live once. I love my sky light and roof vents and we even kept the hatch. Oh yea. We stoped by AmericanRV and bought a standard RV suietank roof vent. I cut the hole in the roof close to the size of the pipe, and used Exterior Heavy Duty Liguid Nails around the pipe. Then we used the very nice gasket seal that came with the rv vent top. Which is screwed down. Also another application of liquid nails over the screws and around the vent top gasket edge again. Kind of "triple sealed". If I had it to do over. Would have read the board and vented in the engine compartment or wheel well. Seems to easy. Just don`t forgot the trap in the shower drain.... Larry | ||
| James Stacy (Jimstacy)
Rating: N/A |
I, too didn't like the idea of another hole in the roof. I ran mine up through a closet with flexible pipe and into the area just below the refrigerator roof cap. Has worked great for more than 5 years. Simple is good. Jim Stacy | ||
| S.M. Heath (Hotspring_44)
Rating: N/A |
I got the "Home Depot" standard sheet metal & rubber flange, Drilled a circle (I did not have anything else to make "Perfect round" hole) it looked kinda slopy but I made sure that the 1 1/2 inch ABS pipe fit snug through both inner & outer skins of the roof. Then I siliconed the around the pipe with 50 year clear silicone(pipe to roof), Cut the sheet metal (with shears) to a proper size for bus roof, siliconed the underside of the sheet metal heavily (Two 1/4 inch beads, one at outermost edge of the sheet metal flange other closer to vent pipe), & slid it over the vent-pipe. pushed it down onto roof(things got kinda messey at that point), Then drilled 1/8 inch holes in both sheet & roof all the way around the flange, siliconed around each individual rivit (one at a time) before inserting them, used a pice of nylon bug screen (stuffed it into the vent pipe)& I used a standard "mushroom" type RV roof vent (the kind that slides an attatched metal flat-spring onto 1 1/2 inch ABS), then painted the whole thing including the ruber seal. 5 years & 10 months ago. it never leaked. I stayd in an extreemly fogy, dewy, El'Ninio riden spot under a tree that sheads heavily more than once per year for 2 winters in a shaded area (even had to scrub the alge from the shady side of bus twice!) NEVER leaked once! It is still good today. 2'nd time painted this spring. seal is still good after 5 winters (in that wet area)& 1 summer in Mojave Desert Sun!. Worked for me, I wold do it like that again. Although the vent into eng. intake might help limit the tailgaters! LOL! S.M.H | ||
| Stephen Fessenden (Sffess)
Rating: N/A |
There is a new venturi top for RV vents that weathervanes into the wind for best venting. Saw it in new products in Good Sams or FMCA. I would use it or copy the idea. My roof vent has been in place for 22 years with no leaks. The commercial type urethane tape I have from 25 years ago is still flexible. I would use that type of seal. I would also put in a 12 volt fan in the vent. I have seen that posted here. Turn it on when you flush. | ||
| Hugh Bavaro (Hbavaro)
Rating: N/A |
My bus smells of waste while on the road. It has all the proper venting, including the "lil stinker" exhaust fan on top of the roof vent. Any suggestions on how to get rid of it? | ||
| H3 (Ace)
Rating: N/A |
Make sure it's not your batteries overcharging! The smell is very similar and often overlooked! Happened to me once! Had all the proper venting and still had the terrible smell. Turned out to be a faulty alternator! Ace | ||
| Marc Bourget Rating: N/A |
Dear Hugh, All smells, apart from their intrinsic volatility, travel down a pressure gradient. (Keeping in mind that volatility is a form of pressure gradient, in a way) This means the source of the smell sits in a higher pressure than the destination, inside the coach where you're smelling it. I always understood busses to be "sieves" but didn't actually grasp the problem until I started the "tearout process". I guess MCI could afford to be lazy about sealing the passenger space if the Coach Air was sufficient to artificially pressurize the interior. (don't know fer sure, just speculating!) It'd be really hard to go back on a completed coach and try to seal all the possible incursion paths. I don't know if it will be possible to do so in a fairly extensive conversion, but, in any case, I'll try. I'd have some real concerns if I could smell overcharging batteries or failing alternators from inside the coach. Due to safety concerns my first impression would be that smelling overcharged batts or alternators inside meant that the batt, genset or engine compartment wasn't adequately sealed and/or vented. But, Ace is more diligent than that and he would have explained any fix that was necessary. More reflection on the point leads me to the conclusion that Ace's bus was adequately vented and sealed but the wind was coming from the right (wrong?) direction and, for example, it was blowing in a open window. Ya can't anticipate everything! It's hard to conceive of a perfectly sealed coach. I'll TRY to seal up things sufficient that external wind direction (except for open windows) won't be a consideration. Hope I'm successful. You'll cure your problem by reducing the pressure within the tank by some extraction mechanism (with more capacity than the exhaust fan) to the point that it's lower pressure than the cabin while you're underway going down the road. A couple of lengths of clear plastic tubing with colored water (one with both ends inside the cabin and the other with one end in the bay) or tank or a magnahelic guage is a way of measuring the situation and verifying the results of changes. Onward and Upward Marc Bourget | ||
| FAST FRED Rating: N/A |
A simple trick used on larger boats is to have a feed pipe that adds air to the waste. With out O2 the black stuff stinks as it decomposes, but with sufficent O2 the "other" (forget which is anerobic) bugs decompose the waste , without smell. Since there is loads of air in a running coach a regulated pound or two fed into a pipe with holes on the bottom of your black tank might solve the hassle. WE solved it with a 2inch almost straight up vent pipe , and a piece of masking tape over the Sealand overflow bowl hole. Works for me. FAST FRED | ||
| H3 (Ace)
Rating: N/A |
Marc, the coach in question was our GMC 4107. It had original type start batteries, placed in the original compartment (steel box). The black vent went up thru the roof and NO windows open. The (correction from previous post)) "voltage regulator" was found to be faulty and overcharged the batteries causing the bad odor. The bathroom happened to sit above the factory steel box. I don't think the coach was sealed up as tight as you may make yours and probably leaked everywhere unimaginable but I do know that once the regulator was changed out, the batteries back to normal, the smell went away! We first noticed the smell on a short trip from North Port to Lakeland. We did not do the conversion. It was home done by another guy. It was our first dive into this wonderful hobby! FWIW Ace... see you real soon! | ||
| Marc Bourget Rating: N/A |
I figured as much. Didn't know enough facts, especially that it wasn't your work. I kinda combined batts/alts because the intent was to inform others and newby's regarding all the "smell holes", not comment on your particular coach. I think you'll agree that if you needed to discover a bad regulator by smell, you wouldn't choose to find out the way that was "pre-"odor"ained" in the 4107. Don't expect a repeat with the H-3, I bet! Onward and upward |