metal fuel pipes (on cars)

[foy9999]

I have had three Mk3 Ford Mondeos and all of them have had very rusty steel pipes running under the car, for the petrol/diesel feed & return.

They connect to other components on the car (tank & fuel-filter) via nylon (PA11/PA12) 'push-connect' fittings.

The original pipes seem to be 8mm & 12mm OD

I have bought a tool which forms the push-connect male shape on the new metal pipe/tubing and that means the new pipes can be clicked into the existing fittings. (IE no arsing about with rubber hoses and jubilee clips)

Anyway. I obviously need steel or copper (yes I know it's cupro nickel) tubing of the exact same diameter as the original.

The seal is formed by a seal inside the female part which grips the tube closely. The push-connect collar formed on the pipe is just for stopping the pipe slipping out. It doesn't do the sealing.

It looks like I can get copper tube in 8mm OD and 12mm OD but not steel.

So where did Ford get steel tubing of that diameter?

 

[Melvyn Best]

I have had three Mk3 Ford Mondeos and all of them have had very rusty steel pipes running under the car, for the petrol/diesel feed & return.

They connect to other components on the car (tank & fuel-filter) via nylon (PA11/PA12) 'push-connect' fittings.

The original pipes seem to be 8mm & 12mm OD

I have bought a tool which forms the push-connect male shape on the new metal pipe/tubing and that means the new pipes can be clicked into the existing fittings. (IE no arsing about with rubber hoses and jubilee clips)

Anyway. I obviously need steel or copper (yes I know it's cupro nickel) tubing of the exact same diameter as the original.

The seal is formed by a seal inside the female part which grips the tube closely. The push-connect collar formed on the pipe is just for stopping the pipe slipping out. It doesn't do the sealing.

It looks like I can get copper tube in 8mm OD and 12mm OD but not steel.

So where did Ford get steel tubing of that diameter?

Try your local hydraulics suppliers?

 

[frank horton]

In the good old days they were copper from the factory.....dont make work for urself....
last time I looked at trucks and JCB's they just used nylon....

 

[ajlelectronics]

I redid mine in Kunifer and rubber. It was far more sensible in my view, when I put the 2.9i into the GTC.

 

[Matchless]

Steel fuel pipe is VERY hard to work with, go with copper or Cupro Nickel, or even nylon,

 

[Morris]

Steel fuel pipe is VERY hard to work with, go with copper or Cupro Nickel, or even nylon,

Got to agree with that. I did the injection flow and return on wifey's pop in Cupro Nickel and it's a job you only want to do once. Can't imagine what steel would have been like.

 

[Smallfry]

Got to agree with that. I did the injection flow and return on wifey's pop in Cupro Nickel and it's a job you only want to do once. Can't imagine what steel would have been like.

I agree. I am struggling with the 6mm Kunifer brake pipes on my Unimog at the moment, despite having a bender. Its not really the bends themselves thats the problem, its shaping and orientating them to fit. I am too fussy, which doesn't help.

All my other vehicles have formed nylon pipes which are quite stiff. PA6 ? PA12 is quite bendy ISTR. I would use nylon myself for fuel. Steel is OK is you have a nice programmed CNC machine to do it.

Edit. The other thing is, that at the factory, steel brake and fuel pipes are one of the first things fitted to a bare shell, when nothing else is in the way.

 

[Morris]

Forgot to say that the fuel line was 8mm.

 

[hotponyshoes]

You can get inserts that have a male stem on one side to insert into the quick connector.
A hose barb on the other side to attach to flexible tube.

Or, does your tool need a particular wall thickness to work?
Stainless seamless tube is readily available in 8mm & 12mm. It's much harder to form than copper or steel but you could use a thinner wall to compensate for that

 

[knighty]

why not just use nylon pipe the full length?

assume you're not going for the show car look etc.?

 

[dave h 2]

Don't forget pipe and tube are measured differently. Tube is OD pipe is ID

 

[foy9999]

so the tool arrived today and, hopefully not speaking too soon, looks like it might work....

I had some ancient 5/16" copper tube and formed ends on it. Very easy to use. Almost no effort required.

On the first one I did the 'collar' formed wasn't very wide so I tried something different on the 2nd one...

When you put the tube in the split-dies you are meant to have the end of it flush with the end of the die.

I positioned it with the tube a little proud and it came out with same length of nose but a wider collar. Ideal.

I then measured the diameter of the tube, hoping that it would be the 7.89mm standard for quick-connect male end, and it is a shade under 8mm. So that's good.

Unfortunately I don't have any female connectors in-hand to test the click-fit.

Regarding the 12mm line. It seems all is not lost......

The tool has dies/adapters for various flares but, as mentioned above, only goes to 3/8 for the push-connect type.

There are however 1/2" pieces (near 12mm) for brake-pipes and General Motors transmission cooler flares.

The GM flares look very similar to push-connect apart from having shorter stubs. This is the case for the smaller sizes (5/16 & 3/8) but for some reason the 1/2 GM/TC one is the same length as the push-connects.

I can't see any difference in the design.

Or in other words the 1/2" GM just looks like another push-connect.

So I'll need to get some 12mm or 1/2" copper tube and see how I get on

 

[foy9999]

Don't forget pipe and tube are measured differently. Tube is OD pipe is ID

Yes. I saw that online. It's only the OD that concerns me really

 

[foy9999]

why not just use nylon pipe the full length?

assume you're not going for the show car look etc.?

I did consider that. I got PA12 in 8mm for the return pipe but had problems finding 12mm and gave up looking for it.

However I just found some on Ebay so may try it.

Problem with the nylon is that it's very hard to get the fittings in and also difficult to bend it to a fixed shape. I experimented with heating it to for bends/curves and it wasn't a a big success

 

[truckdoctor]

Have you thought of using aluminium tube ,easy to bend and various sizes https://www.ebay.co.uk/sch/i.html?_...pe=e&msclkid=eef04885fb4219a3739d20250e89b1bd

 

[Porkypine]

I used copper on the Morris Minor, which seems satisfactory and easy enough to deal with, the original steel was getting very manky

 

[foy9999]

Have you thought of using aluminium tube ,easy to bend and various sizes https://www.ebay.co.uk/sch/i.html?_nkw=aluminum fuel line&norover=1&mkevt=1&mkrid=710-55005-18975-0&mkcid=2&mkscid=102&keyword=aluminum fuel line&crlp=_&MT_ID=&geo_id=&rlsatarget=kwd-81707590193298:loc-188&adpos=&device=c&mktype=&loc=41230&poi=&abcId=&cmpgn=373198558&sitelnk=&adgroupid=1307319529695099&network=o&matchtype=e&msclkid=eef04885fb4219a3739d20250e89b1bd

I didn't think of that actually.

Didn't know it existed lol.

Thanks