1.8 Fuel Lines

[DaveW]

Next job on the list is to replace all the fuel lines. I was rather hoping that I could find a 'ready-made' complete kit of parts to use for this exercise. Auto Atlanta seem to have 'lower' and 'upper' kits and confusingly it would seem that the 1.8 has differing diameter lines to the 1.7 / 2.0 if some of what I have found on forums stands true.

Has anyone else sourced a complete kit (including replacement injector elbows and clamps) that they could recommend? Is Porsche a sensible option? Looking for confirmation on the bits that are different for a 1.8 FI too?

Suggestions please?

[bluemonk]

I replaced all of mine recently, a job which I would recommend doing! For the plastic pipe that runs under the floor I used 8mm copper tubing and soldiered on an elbow on the end at the rear. You need to remove the fuel tank and pull the new pipe through using the old one as a pull. The rubber hoses I used were 7mm which are a good fit on the 8mm copper.
Hope this helps


Al

[DaveW]

Cheers Al. Do you run a 1.8? Happy for someone to tell me that they are all the same however some of the posts on 914club seem to say otherwise. The 1.8 is a complete loop fuel system (L-Jet) which I understand is different from the 1.7/2.0 cars too...?

[bluemonk]

Can't help you with that one mate as my car is a 6 conversion. Kev will be the man to ask

Al

[914 KEV]

Happy for someone to tell me that they are all the same however some of the posts on 914club seem to say otherwise. The 1.8 is a complete loop fuel system (L-Jet) which I understand is different from the 1.7/2.0 cars too...?

Can't help you with that one mate as my car is a 6 conversion. Kev will be the man to ask

The 1.7, 2.0 and 914-6 also have a complete loop fuel feed, the only 914 which didn’t, was the European Spec 1.8 running twin Solex 40 PDSIT Carburettors which had a single feed with mechanic fuel pump.

David your 1.8 is a 75 model year, which is different from 70-74 models. (1.7, 1.8, 2.0)

Here is a list of the Fuel Line changes starting from the front of the 914.

Please note I have marked the hose connections size with the fuel hose inside diameter.

Up to the 74 model year, the fuel tank hoses were 9mm Out and 7mm Return. From 75 it was 7.5mm Out and 7mm Return.

Up to the 74 model year, the fuel filter and pump was originally located in the lower right-side of the engine bay using a fuel filter with 7mm hose connections and a pump with three pipe connectors for 7mm hose.

From 75, the fuel filter and pump was located under the left-side of the fuel tank using a fuel filter with 7.5mm hose In and 11mm hose Out.
The two connector fuel pump has an 11mm hose In and 7mm Out.

Up to 74 model year, the plastic pipes through the body were white with 9mm hose connection for the line to the fuel filter and 7mm hose connection on the return, both with straight ends in the engine bay and metal ends fuel tank end.

From the 75 model year, the plastic pipes through the body were black, both the same size with 7mm hose connections with flanges on the end in the engine bay and metal connections at the fuel tank end. The outputs in the engine bay continued through the engine shelf to the right upper rear of the engine bay.

Up to the 74 model year, the output of the large plastic hose to the fuel filter used a reducing hose (9mm to 7mm)
From the fuel pump, hoses were connected to a Y piece and two plastic hoses that go through the engine shelf to the right upper rear of the engine bay.

From the fuel filter Out 70-74 (1.7,1.8,2.0) and the plastic lines 75-76 (1.8, 2.0) in the engine bay, all fuel hoses were 7mm and the fuel rails to the injectors were the same on all models.

The hose to the injector were original crimp on with a 90 degree bend.

Back in the mid 70s, the 914 had a recall (HO Campaign) to replace all the engine bay over-braded lower pressure fuel hoses with high pressure smooth hose.

[914 KEV]

On all the 914 I have owned and still own which is quite a few, I personal never found the need to replace the plastic lines through the 914 body.

The ends in the engine compartment can go brittle (due to the heat) and can get folded by heavy hands and damaged by over tightening.
I cut out the damaged bit and replace with fuel hose.

If a 914 has had a lot of bodywork done on the central floor pan area, the plastic fuel lines can get damaged in the tunnel if not removed or protected while work is carried out.

If you can smell fuel inside you 914, most of the time it is not these plastic lines, but caused by one of the following:

Fuel hose at the bottom of the fuel tank, the fiber washer or strainer on the fuel tank lower connector, pinhole in fuel tank, seal to filler neck or fuel gauge sender seal, fuel cap fiber seal, overflow pipe disconnected, breather hose to expansion tank disconnected.

Replace the fuel hoses with the current fuel injection hose spec, now fitted to all new cars, SAEJ30R9, commonly known as R9 as the other lower spec fuel hoses will be affected by the high level of ethanol now in petrol and can cause fuel hoses to leak as they are not compatible with the high levels of ethanel now in the fuel.

Please also note, normal unleaded fuel in the UK will be changing soon... from 5% ethanol(E5) to 10% ethanol(E10) as more ethanol is added to the fuel mix.
Many countrys in Europe and around the world have already introduced E10. Super unleaded is staying at 5%.

[DaveW]

Fantastic. Thanks for all the information Kevin. I think I need to sit down now and have a drink

It was just what I needed though if I am unable to locate a kit. At least I can source the pipework myself independently with the right sizes in mind now.

Cheers.

[DaveW]

Spent the evening searching online for R9 high pressure fuel hose in 7mm form and cannot find any anywhere...is the 7mm converted from the US 5/16"? In which case I can locate 7.6mm and 7.9mm hose but struggling to find 7mm.

[EDIT, just found some specified as 7.3mm (5/16) from AFS... can I assume that this will be ok once tightened up vs 7mm? ]

Does anyone have any suggestions as to who they have used?

[914 KEV]

The hose inside diameter I quoted is a nominal figure.

For some time now, most of the high pressure fuel injection hose I have seen has been marked as the metric equivalent of the American standard sizes.

I have been using hose marked up as 5/16 or its metric equivalent for many years. It is tight on the connection, clamping it in place with the correct type of clamp, one with a screw and nut (Norma Type Clamp) not a worm drive clamp (The traditional Jubille Clip).

Fuel hose nowadays have a larger outside diameter than the hose available in the past; you will find the old clamps will be too small. As a general rule, I replace the clamp with a new one when I replace the fuel hose.

I have been using AFS for some time, as here in the UK other fuel hose suppliers have been slow with the changes which have be made to the petrol available now and the future changes, as well as the fuel hose used on all new cars.

There is a bit more choice on the brand of R9 hose available in the UK now.

[MikeH]

I'm not sure on how feasible this is with the fuel lines being routed inside the body, but in the past I've made injection fuel lines from 8mm copper pipe, and added a slight swage on the end using a brake pipe former, then made the flexi ends with 7 or 8mm 12 bar fuel hose.

You can buy the copper pipe as 8mm gas pipe, or as truck brake pipe. It's cheap and readily available, as well as easy to shape with an external bending spring (also from plumbers' merchants / heating suppliers).

[DaveW]

If the central 'plastic' pipes need replacing, that is exactly what I had in mind for those Mike. I have now ordered 100% Ethanol compatible injection hose from AFS for the rest.

[LMR]

Just picked up on this old thread. Has anyone replaced the pipes in the centre tunnel? What materials have you used? I can see that if something isn't broken then no need to fix, but with a car as stripped as mine, it seems to make sense to change them whilst I can.

[jackstowers]

Just picked up on this old thread. Has anyone replaced the pipes in the centre tunnel? What materials have you used? I can see that if something isn't broken then no need to fix, but with a car as stripped as mine, it seems to make sense to change them whilst I can.

Mines is copper. Only one as I'm running carbs and have done away with the return.

[AndrewSlater]

For info, TangerineRacing in the US make a nice set of stainless replacement lines.

I was considering this job on my 914 whilst the fuel tank was out, but the grim exchange rate put me off ordering a set.
Andrew

[LMR]

Andrew

I am in touch with Tangerine Racing. The exchange rate is terrible, as is the shipping costs. Then there is VAT......