Black Tank Grommets

DancinCampers · 10-17-2007, 03:02 PM

Here are some pics of the toilet & vent grommets I received. Not installed yet.

Toilet side & top view:

Vent side & top view:

Notice they both have inside lips on the bottom. I can't remember if my toilet has this lip or not, will have to check during install & make sure the flange pipe is not too long. The lip on the vent grommet should prevent the pipe from slipping down into the tank.

This is another project to do after our upcoming trip.

DancinCampers · 10-17-2007, 03:02 PM

Here are some pics of the toilet & vent grommets I received. Not installed yet.

Toilet side & top view:

Vent side & top view:

Notice they both have inside lips on the bottom. I can't remember if my toilet has this lip or not, will have to check during install & make sure the flange pipe is not too long. The lip on the vent grommet should prevent the pipe from slipping down into the tank.

This is another project to do after our upcoming trip.

Slapshottr · 10-24-2007, 03:59 PM

Thanks for the update. A few weeks back you provided me with some advice about the grommet on my toliet as being the cause of a leak. I have a few questions. Did you buy the grommets from a local RV dealer or did you have to special order them? How much did they cost? I have not made the repair yet.

DancinCampers · 10-28-2007, 10:35 AM

Slapshottr,
I ordered from Lichtsinn Mts in Iowa, we don't have an RV store in town.

My receipts are at home, will be there in about a week, but I don't think they cost more than $8 each plus ship. I'll check when I get home.

Slapshottr · 11-05-2007, 03:53 AM

Thanks Dan for providing me with the numbers on the grommet. I have a few more questions about the fix. I have taken some photos and hopefully they post on this thread when I figure out how. It keeps on telling me they exceed the file size and I haven't figured out how to make them smaller.

I pulled the toilet off and did confirm the leak was at the connection of the black PVC toilet pipe and the grommet. Here is how I tackled the problem for those who have a similar problem. My problem is not a pipe slipping into the tank or a cracked grommet but appears that the black PVC pipe leading from the flange into the black water tank was cut to short.

First pulling the toilet and just looking at the flange and pipe gave me a lot better view of the grommet. All appeared OK. I used a garden hose and filled the tank to confirm at what point the leak started. Interesting to note when it hit the bottom of the grommet no leak, ½ way up the grommet no leak.

Leak started when water level started up the black PVC pipe.

You talk about the lip on the grommet and feel this is to prevent the pipe from slipping into the tank. Mine has this lip on the bottom and I agree. My first question is: how far into the grommet does your black PVC pipe go? Mine stops well short of the bottom and I feel the pipe should have been cut so it would rest on the lip and that would act as a gasket.

I pulled the flange and confirmed the pipe was glued to flange. Black PVC had a mark around the outside formed by the connection to the grommet. It was only 7/8" and could have gone another 1 ¼" to the lip on the bottom of the flange. Had I been able to post the photos you would see from that the water shot up and out between the pipe and grommet. The cut on the pipe was very rough and uneven. The only thing I could think of at this point was beware of things made on Monday. For those who have a 38T pulling the flange will give you a good view of the top of the black water tank and grommet.

The leak was confined to one side of the grommet and lucky for us it was close to the outside of the tank and just ran down into sewer compartment. Wearing rubber gloves and cleaning the area I also inspected the grommet. It appears to be well secured with no cuts or cracks. I was surprised it is soft rubber but makes sense.

Second question: Did you do anything special to help get the pipe into the grommet? I was thinking of putting a little liquid soap on the pipe to help it slide into the grommet. Wasn't sure if this would compromise the seal. Hopefully cutting a longer piece of pipe will solve this problem.

At this point my keyboard is burning up. I'll end it here. I plan on purchasing the parts today if they are available at the local RV store. I plan on doing the repair over the weekend.

Clay L · 11-05-2007, 05:21 AM

I used some dish soap on my 96 and it sure made it easier to push the pipe in.tou
I am not sure why yours is leaking (mine was split) but I don't think it's because the pipe doesn't rest on the ridge at the bottom of the grommet. That would require a lot more precision than is going to be possible in a manufacturing environment.
As I recall mine went all the way through the grommet and extended maybe a couple of inches into the tank.

I would probably replace the flange and pipe and make the pipe longer.

Slapshottr · 12-03-2007, 04:48 AM

Just wanted to provide some info on my fix to this problem for those users owners who may have to deal with this. I won't go into a long discussion on the problem and diagnosing it. If you need some background info please reference the following posts.

Toilet connection to black water tank leak. Posted Sep 24, 2007 by Slapshottr

http://irv2.infopop.cc/eve/forums/a/tpc/f/2486094452/m/8921005734

Black Tank Grommets Replaced Posted Nov 18, 2007 by DancinCampers

The problem: Black water tank leak. Black ABS pipe connecting flange to black tank was cut to short.

The fix: Purchased a new flange $5.55 and grommet $7.70 from Lichtsinn Motors 1-800-343-6255. Note the flange part #116644-01-000 3" Female-4 bolt is listed in the Winnebago parts catalog found on line for a 2006 Itasca 38T. Lichtsinn rep said this has been changed to part #024676-01-000 3" Female-2bolt. Recommend staying with a 4 bolt flange because holes holding flange to floor on 2 bolt do not match up.

I ordered a new grommet but did not have to use it because old grommet was in good shape. I believe in the KISS principal Keep It Simple Stupid.

Found a 4 bolt flange at local RV dealer that matched mine the only difference it had threads in it. Purchased 3" ABS male adapter $3.17 and 2 ft section of black ABS pipe for $2.97 at Lowes. Spoke with Winnebago who confirmed pipe has to sit on bottom lip of grommet. The key is an accurate measurement for the length of pipe and smooth cut. Use a PVC saw and you will have no problem. Cut pipe, glued it to male adapter. As recommended by other forum members I used hand soap on bottom of pipe to help it slide into grommet. By not having the flange on I was able to fill black water tank all the way to top of pipe and observe the grommet. I am happy to report no leaks. Screwed flange to male ABS adapter and bolted flange to floor. Replaced flange seal on bottom of toilet which probably should be done anytime you pull the toilet. This flange seal was $3 and change.

Traveling home after dry camping and not having to clean up crap PRICELESS