Pipe couplers in resilient materials.

[julianf]

I asked this question some years back and gave up and implemented a tempory solution.

But I'm now back needing the same again!

I need to join two steel pipes (part of a fuel tank) with a 75mm ID coupler.

And then the same again with a 56mm (approx) ID coupler.

Has to be demountable. Not routinely at all, but it can't be welded.

Easy... Just go on eBay and grab some silicone tube.

Except silicone is no good for the job. Needs to be somthing like PU, Viton, PTFE etc.


All I need is couplers. Maybe as little as 50mm lengths?


Any ideas? I mean I can Google viton hose as well as the next man, so I'm looking for more "call here and speak to Dave" sort of answers, rather than "this place sells 8mm viton hose, they may be able to help" kind of comments! : )

I guess this time, if I can't do better, I'll use silicone. It will fail, but probably not as quickly as nitrile.

Thank you.

 

[AKN]

I couldn’t swear to the diameter but take a look at the fuel tank on the Range Rover Classic there’s a coupling pipe about that diameter which is fuel proof Between the fuel filler and tank.

 

[8ob]

If these joiners are not permanently submerged you can use fuel resistant hose. Filler hose is made by Mocal in those diameters .

Bob

 

[julianf]

It's on the 101.

The large bore one will be submerged, kind of. As in I'm planning on making up an elbow that will mate up to the flange on the tank.

The original filler pipe has an elbow, but you have to cut it for the ambulance anyway, and fit a metal extension. I'm wanting to do away with the original hose that just decays and make the elbow in metal and then couple it to the tank on one side (which will be constantly "under" but only so much as the crack between the two metal parts) and the filler on the other side - which would be "under" if you brimmed the tank, but only until you drove 10 more mtrs down the road....

 

[julianf]

I couldn’t swear to the diameter but take a look at the fuel tank on the Range Rover Classic there’s a coupling pipe about that diameter which is fuel proof Between the fuel filler and tank.

I considered getting the filler hose off somthing else and cutting that up. Even looked at defender hoses online etc but the replacements seemed to be made of different stuff to the originals anyway, which lowered my confidence.

I wondered if some truck or other would have the right diameter hose, and then remembered that truck parts cost about a million pounds each, and scrapped that idea too!

But, yes, if I could find the right diameters in another landrover and then maybe buy OEM that may well work.

 

[julianf]

Ps. It will all be some imperial measurement anyway.

75mm is probably actually 3" and 56 is 2 and some fraction or other.

So if there's another that seems the same then it probably is the same even if its a mm or two different, if you see what I mean?

 

[Ross365]

Place I worked at used stainless braided PTFE hose for everything, and we had someone make them up with all kinds of end fitting in all kinds of lengths. Sadly, I cannot recall who made them but they are out there!

 

[dan.taylor.1]

No way of welding a flange to either pipe and using a viton o ring between them?

 

[8ob]

No way of welding a flange to either pipe and using a viton o ring between them?

Dan the filler tube and couplings on these 101 land rovers take a bit of a torturous route to the tank, virtually no working space at all. whichever method used it needs to be the right fit/length. I junked the whole lot on mine and found a rubber truck filler tube that fitted, a lot less grief.

Bob

 

[Sergei Slovenija]

corrugated stainless steel bellows pipe, no?

 

[Wildefalcon]

Do you have any photos of the pipe run?

What I'm thinking is some sort of steel sleeve arrangement, with a viton O ring, for the submerged join. Like a quick connect, but larger.

 

[julianf]

Do you have any photos of the pipe run?

What I'm thinking is some sort of steel sleeve arrangement, with a viton O ring, for the submerged join. Like a quick connect, but larger.

You'll have to partially trust me (and 8ob) on this, as the diagrams make it look easy...

This is the diagram from the manual -

But this is a photo of the actual thing -

Sure, it still looks easy?

What happens is that the diagram is from the GS build. On the ambulance the pipe must be cut and reassembled around a hard pipe to lengthen it.

The fuel tank itself is in a cradle, and the assembled pipe won't (iirc) fit through the cradle, so it needs to be assembled in situ. And there's no real access to the other side, so it's all up the gaps in the body work. I mean it's possible, I've done it, and that's not the reason I want to change the arrangement anyway. But I mention all this to highlight things are not easy.


If you were to weld a flange onto the tank spigot, it would no longer fit through the cradle, so that's not an option. You could, I guess, also modify the cradle.

 

[Wildefalcon]

Yes, I get why the flange doesn't work.

Would a steel sleeve over the tank output work? Sealed with an o ring and a kictking ring?

 

[julianf]

Im not familiar with that method, but it looks like it might work.

Id still need hose for the upper section, but thats not as important, as its not "under" all the time. The bit at the bottom is more critical, as, because the filler is on the side of the tank, its always submerged.

 

[Wildefalcon]

It's the principle behind "quick connect" plumbing. I don't like it, as I don't trust it, but it might do what you want to do.

 

[Wildefalcon]

The access on the GS isn't too bad. But this shows why the filter is always in petrol.