Fuel line damage. Any ideas?

[marlinspike]

Morning. Whilst changing the fuel pump on my Saab 900 1992, we managed to snap off the old fuel return pressure valve. The new one is the new white bit in the photo. The remnant of the old one is stuck in the fuel line. Nothing so far has shifted it. You can grip it with pliers but it won't move. We put a screw in to see if that would free it but no luck.

The plastic line runs right to the engine so swapping the whole thing is a big job.

The ends of the pipe are shaped round the valve end - not sure if they are manufactured that way or have just formed round the valve over the years.

Any ideas on how to proceed? Cut the pipe off and push the valve in, and hope that it's still long enough and the shaped bit doesn't matter? Cut it off and add a short piece of new fuel line with a jubilee clip? Is that safe?

The new valve looks huge in the photo but it's the right size and will fit if we can get the old bit out.

 

[DanZac]

Have you tried warming it up to see if it softens the pipe and gets a bit more flexible allowing you to pull it out?

I'd try a cup of boiling water and see what that does.

 

[marlinspike]

That was on the cards but was a bit worried it might make it tighter lol.

 

[jsf55]

Boiling water all the way, a good gripper and tug on that screw with mole grips !

 

[Wildefalcon]

Yep, boiling water should be fine. Mapp torch, not so good.

Get it turning first. Resemble when hot.

 

[MetalMonkey]

Those nylon pipes have to be heated, there are actually special insertion tools for pushing in the fittings, but with enough heat you should be able to brute force it.
Boiling water as suggested is the safest way to do it, for obvious reasons.

 

[mr haynes]

Yes hot water is the safest way to go, as above the pipe has to be heated.
2 nuts on the straps and couple of pipes will drop tank if struggling to get the banana fingers in

 

[voipio]

That new part's barbed push on fitting looks a lot larger than the original. It's 51.4 pixels across, vs 52.2 pixels for the old one with the tubing over it.

 

[Morrisman]

If it's so brittle and stiff that you can't get the old stub out then you'll have just as much trouble getting it onto the new pipe stub, and getting it to seal, and stay on.

Hot water sounds like the best plan, if you can get the pipe into some.

 

[James1979]

If you can’t get hot water near it then heat gun. There’s probably a couple of cm slack in the system if you look for it

 

[Nomad]

+1 for hot water, I normally fill a cup then leave the end of the pipe in there to warm through. Refill with more hot water if needed to get more heat into it.

It might be ok to drill the centre of the snapped piece slightly oversize to weaken it, it might help you to work it loose.

Is that the return line or the feed? Return will be under very low pressure so I'd say is safe to put a joint in the pipe, the pump is in the tank so the feed line is under pressure so I'd avoid putting a joint in that line.

 

[marlinspike]

It's the return. It's definitely the same size as the old one, though it looks huge in the photo I know.

 

[Keithmac]

They are designed to be fit and forget, you'll probably end up cutting the line shorter.

Same with new one you only get one go at fitting it..

 

[Screwdriver]

Cut it off, bond a new extension piece over the old hose. Make sure it's the correct size for the new fitting!

The new part looks a fair bit bigger than the old hose....

 

[PhillipM]

Yep, I always fit those nylon lines with a heatgun, they shrink when they cool around the fitting, they never come back off unless you reheat them (but you should really only do it once anyway as it deforms the tube permanently to seal)

 

[Ubique]

Just to go against the grain.... as noted, the pipe is 'fit once' (they're not actually nylon, which doesn't shrink as these do, they're usually a blend or laminate of various plastics) the chances of getting the remnants out and fitting the new one with two applications of sufficient heat are slim IMO, What I'd do is leave the remnant in the pipe as a stiffener and fit a short length of fuel hose over the pipe and the new barb, fixing with the correct size single ear sleeved clamp like these

 

[8ob]

As this is only the return line you could push an insert into the nylon tube and use a short piece of rubber with two hose clips.

Proper tool for pushing barbs into nylon tube is this gadget, different collet sizes for gripping the outer and a mandrel pushes in the barb.

 

[locos]

As this is only the return line you could push an insert into the nylon tube and use a short piece of rubber with two hose clips.

View attachment 403045


Proper tool for pushing barbs into nylon tube is this gadget, different collet sizes for gripping the outer and a mandrel pushes in the barb.

View attachment 403047

View attachment 403048

Any links to a UK supplier of this tool please

 

[marlinspike]

I forgot to update this. We tried the boiling water trick a few times with no luck then did as suggested and used an extra length of hose and clips. No problems so far.