# Anyone changed the Autotrail waste drain pipe?



## cossieg

Hiya
I've now grounded the waste pipe on my Comanche twice and come close to tearing the whole thing out of the tank. Luckily all I've done so far is pull out the self tappers that hold the valve bracket up into the bottom of the side locker. The arrangement is far too low beneath the vehicle in IMHO. 
I was thinking of taking off the 40mm pipe at the tank, fit a 40mm-25mm reducer then fit a flexible hose with small valve on the end secured with a length of chain like the fresh water drain. 
Has anyone done anything else similar or better?
Cheers


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## peedee

It will drain a lot slower and small bore pipes are prone to blocking up. Is there no way you can fix it higher?
peedee


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## cossieg

Hi Peedee

Understand entirely that I may have problems with smaller bore pipe work and appreciate your thoughts but I think that 25mm should be adequate given that the tank should only ever have water in it. 

I don't think there's anyway of lifting the pipe higher as it comes out of the tank on a regular connection and then does a right angle turn and that part seems fixed. 

I was thinking of cutting off the pipe at the tank, fitting a 40mm flexible pipe and valve so as to keep the pope diameter but it's proving difficult to find a suitable 40mm valve.

Thanks


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## spykal

Hi

Not an Autotrail but on our Autocruise ....I changed the fixed pipe for a flexible one.

see picture below and Old thread << for details.










Mike


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## Mrplodd

Rubbish design isn't it? 

On my Cheyenne the waste outlet from the grey tank is THE lowest point of the vehicle, ludicrous. Had the same problem on an earlier Dakota, I actually tore the fitting out of the bottom of the tank. Easily fixed ( on a campsite in Annecy) with a couple of self tappers and tube of silicone. Mrs Plodd was annoyed because she kept asking " why do you carry all that stuff, you will never use it". Silence is golden!!!


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## peedee

cossieg said:


> I was thinking of cutting off the pipe at the tank, fitting a 40mm flexible pipe and valve so as to keep the pope diameter but it's proving difficult to find a suitable 40mm valve.
> 
> Thanks


Have you tried >CAK Tanks<
peedee


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## trevorf

Not sure if its the same design as my Apache. The problem I found was the rigid mounts holding the waste valve to the underbody. I removed them and replaced with straps made from webbing. 
Now when the valve hits the ground it just flexes up without breaking.



Trevor


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## listerdiesel

By definition, the drain needs to be at the lowest point, but it can be a problem if there is insufficient height to get the tap in and the curve of the pipe to an outside position.

You could fit the tap at the end of the pipe on the skirt of the motorhome, that would help, but you've still got the issue of a tight 90 degree elbow to fit to the tank.

40mm is the current standard for waste pipes, but the old 23mm works fine for us, we could change if we wanted to but quite honestly it is never a big issue. The biggest problem is the actual sink waste itself, which is fairly restrictive.










Our shower and hand sink drains come out on one side of the trailer and the kitchen sink the other. All are in 23mm piping.

Peter


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## Bikeboy

Hi,
My first post ever!
One of AT's little weaknesses.
We bust the waste pipe on our 05 Cheyenne 630LB (Merc) coming off an ordinary pavement. We had scraped it before.
I bought a plastic 40mm ball valve on eBay for about £20 and a 3metre length of high density 40mm waste pipe (same dark grey colour) from Wolseley Drain Centre.
I used a 90 deg bend straight from the tank, a straight horizontal pipe to the ball valve, then a short exit pipe with a 45 deg bend.
I shortened the suspension rod (and incidentally made a stronger top attachment) so that the pipe just went downhill.
The bend on the old pipe was a push fit on the tank spigot with a bit of tape to make the joint tight. I did the same and used some silicon grease as a sealant. It didn't leak. I figured it was better not to be stuck on if it got broken again. A strap would be belt and braces.
I gained about 3 inches extra clearance. I can't measure now because we have just sold the 630 (and are looking).
It worked fine, never had any other trouble in 3 years.
I usually tried to keep that side of the van down when emptying, and left the valve open for the run home.

All the best,
Mike.


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## Zebedee

Bikeboy said:


> Hi,
> My first post ever!


Fork out the cash and join!

The forum needs members like you! 

Dave


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## 747

Good post Bikeboy.

Take no notice of Zebedee. At the rate you are posting it will be another 32 years before you need to join.  

So don't waste your posts. :wink:


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