Wedge fuel hose recommendations.

[mrzigazaga]

Hi Peeps

I know this subject has bounced around more than a rubber G-string but a few months back I decided to change the fuel hose run from Swirl pot to fuel rail, I bought up-to-date marine fuel hose that was recommended for all fuels including those with high ethanol content....However I can actually smell fuel permeating through the hose already, There is nothing leaking but you can smell the fuel all the way along the drivers side and on the feed in the engine bay.

My guess is that I was probably sold old stock or hose on the cusp of the change in the ethanol content....I would prefer not to die in a ball of flames via a fuel sprinkler system so has anyone else had any issues like this...Can anyone recommend a good supplier please, The one I used has been good albeit expensive the last 6 years...


Thanks

Regards


Ziga

[adam quantrill]

Zig don't use rubber except at the ends, use cunifer, with short rubber bits to join to the ends.

You can get lorry brake pipe from motor factors with the same inner diameter.

It can take an enormous pressure.

[phillpot]

adam quantrill said:

You can get lorry brake pipe from motor factors with the same inner diameter.

For whatever reason metal pipe tends to be sold/measured by its outer diameter whereas flexible pipe, rubber PVC etc. tends to be done by its inner diameter.







Bit of 8mm Kunifer pipe should do the job

[mrzigazaga]

Thanks for the advice...I do have copper on the return but the feed is all hose....I think id feel a lot more assured with a copper pipe...


Cheers

[The Hatter]

I think the problem is temperature, not ethanol. Is the pipe running down the tunnel in the middle of the car?

I had quite new R9 hose crack externally on my engine's fuel rail. Look carefully at the spec of the hose and make sure it's good for approx 125 DegC, some hoses are only rated up to 80 DegC, that's clearly too low. I put Gates hose rated to 135 DegC on last time, it's been OK so far.

Edited by The Hatter on Thursday 16th March 15:34

[mrzigazaga]

The Hatter said:

I think the problem is temperature, not ethanol. Is the pipe running down the tunnel in the middle of the car?

I had quite new R9 hose crack externally on my engine's fuel rail. Look carefully at the spec of the hose and make sure it's good for approx 125 DegC, some hoses are only rated up to 80 DegC, that's clearly too low. I put Gates hose rated to 135 DegC on last time, it's been OK so far.

Thanks Martin.

I had to replace the fuel rail hose twice in 6 months...Yep hose running in the tunnel.

I have used this
http://www.advancedfluidsolutions.co.uk/73mm-id-51...
and then the R9....Maybe go for Gates or something similar....I did hear that copper can suffer from fuel evaporation from the heat from exhaust etc......??

[adam quantrill]

I had mine (cunifer) in the tunnel on the 350i. No problems.

[mk1fan]

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

Some reading on fuel lines. The last three are the same 1st post in different forums and different info is given in the replies.

[mrzigazaga]

Cheers for all the input , Im going to go for the copper feed & Return with rubber ends....I think it will outlast me that way...


Ill let you know how it goes....

[adam quantrill]

Zig I just found a recommendation to not use pure copper because it gets very slightly dissolved by fuel, and over time deposits build up in the injectors.

So use an alloy (e..g cunifer like I did.)

I was about to recommend copper microbore pipe - I have some spare - but not such a good idea.

[v8s4me]

There's a similar thread to this on the 'S' Forum with lots of interesting views. In the end I decided to go for 8mm copper pipe with Gates rubber hose from Car Builder Solutions on the ends where regular inspection is easy. The copper worked out at £1.39 per meter. This compares with cunifer at £2.50 per ft. Big difference.

adam quantrill said:

Zig I just found a recommendation to not use pure copper because it gets very slightly dissolved by fuel, and over time deposits build up in the injectors.....

Not heard this one before. "Over time"? What sort of time are we talking about here? Months, years? Could the same not be said for rubber hose as it gets old and starts to harden and crack? I think I'll just pop an inline filter in the run just before the fuel distributor head.

I've been practicing soldering 8mm olives on the end on the pipe to give the clamp something to bite against and stop the rubber hose slipping off. It works well but heating up the pipe means it hardens so any bending will be easier before soldering on the olive. I'm thinking this might be over engineering it though and I doubt I'll put olives on the low pressure return line.

[phillpot]

v8s4me said:

heating up the pipe means it hardens so any bending will be easier before soldering on the olive.

Standard plumbers solder melts below 200 degrees C. not enough, I wouldn't have thought, to have any significant hardening effect on the pipe?
And it's only the end inch or so getting that hot, unlikely to want a bend that close to the end.

[v8s4me]

You'd be surprised how far the heat conducts up the pipe even using a soldering iron, it's more like the first 6" or so. I'll try some electrical solder tomorrow as I think that melts at a lower temperature. Anyway, it's not so hard it won't bend at all, it's just stiffer than straight off the coil when it's very soft and bends easily by hand. After heating it bends easily with my little pipe bender so not an issue really.

Edited by v8s4me on Thursday 16th March 23:25

[mrzigazaga]

phillpot said:

Bit of 8mm Kunifer pipe should do the job

I was thinking this...Not from the local plumbers...

[phillpot]

v8s4me said:

You'd be surprised how far the heat conducts up the pipe even using a soldering iron

Not if you wrap some damp rag around it


Are you using a blow lamp or a decent sized soldering iron?


Although, knowing you, it's more likely one of these

[v8s4me]

phillpot said:

...Are you using a blow lamp or a decent sized soldering iron?.......

Tried both.

phillpot said:

...Not if you wrap some damp rag around it .....

That's a good idea

[Wedg1e]

mrzigazaga said:

Thanks for the advice...I do have copper on the return but the feed is all hose....I think id feel a lot more assured with a copper pipe...


Cheers

Should be the other way round, the copper should be the high pressure line from the pump to the fuel rail, with rubber for the LP return.
I got mine from some online seller, not sure what make/spec but after a couple of years neither I nor the car have gone down in a blaze of glory so I guess it's OK.
Anyway, leaking brake fluid ignites a whole lot easier than a bit of fuel vapour...

[mrzigazaga]

Wedg1e said:

Should be the other way round, the copper should be the high pressure line from the pump to the fuel rail, with rubber for the LP return.

Thats what I always thought Ian...Its definitely the other way round....???

[The Hatter]

I was concerned using the rigid pipe without some kind of roughness/barb to stop the pipe slipping off, although TVR did just that. The fuel rail has loads of connections without barbs too.

I experimented with 8mm gas compression fittings; I tightened the fitting to get the olive to clamp onto the pipe and then cut the compression nut to get it off the pipe. Worked OK and no heat involved. I did this on the main fuel feed to the rail where you get pressure, heat and engine movement/rock all working together...

[mrzigazaga]

The Hatter said:

I was concerned using the rigid pipe without some kind of roughness/barb to stop the pipe slipping off, although TVR did just that. The fuel rail has loads of connections without barbs too.

I experimented with 8mm gas compression fittings; I tightened the fitting to get the olive to clamp onto the pipe and then cut the compression nut to get it off the pipe. Worked OK and no heat involved. I did this on the main fuel feed to the rail where you get pressure, heat and engine movement/rock all working together...

Thanks for the info Martin.

I did wonder as regards to this and the kind person who will be fitting it for me has the the tools to put a lip at each end of the pipe...Although it should in theory be okay with the rubber connections pushed tightly on and then clipped.

Ill probably go for a finished end rather than a plan one...


Cheers