I am finally starting to restore a 1973 914 that's been sitting in my garage for 13 years. Removed the fuel tank, the fuel pump and filter which were still in their original location under the engine. The plastic fuel lines in the tunnel are original also. Porsche experts universally recommend to replace the plastic lines. Preformed stainless steel lines are available from the usual internet sources, however, they are not inexpensive at $75. Then I saw polyesthylene tubing made for Watts Manufacturing, N. Andover, MA. at Lowe's and Home Depot. 5/16 OD, 10' long for $4.99. Described as suitable for solvents and fuel. I called Watts Mfg and spoke to a technical adviser who confirmed that this tubing is quite impervious to gasoline and can be used for my purpose.

Any experience with polyethylene tubing?

RenoRoger

That would be "universally" except for me and a bunch of other seasoned 914 wrenches. If they're good, especially where they exit the tunnel, I recommend leaving the original lines alone. Nearly all failures can be attributed to owner/mechanic abuse or error. If I were changing them, I would go with Tangerine Racing's SS lines, especially if the car is apart. Note that the supply line is 9mm, not 8mm. $5 fuel lines are like a $29.95 brake job, they can end up costing you a fortune in the long run.

The Cap'n

Chris Foley / Tangerine Racing Fuel Lines.

The way to go...........I sleep well at night!!!

Fuel line issues..... are something that should and can be avoided.


Vysoc

If you need to weld underneath the tunnel at the rear, or on the rear firewall near those lines, it's most likely going to melt the lines.

Remove and replace as needed....otherwise leave them till you melt them.

I just did not like the idea of having 40 year old plastic lines. I swapped them out for the stainless. No carbeques for me.

Some things you should not cheap out on are fuel lines.

The original tubing is Nylon 6. DO NOT use polyethylene, it has a very low heat rating and you will be pushing fuel through it in a hot engine bay. Carbeque virtually a guarantee.

I like The SS fuel lines Chris sells, but an alternate argument can be made for simply replacing them with nylon 6 tubing per the original.

If you don't want to spend $150 on ss lines, the cost of repairing, let alone restoring your 914 will be an eye opener.

If you are on a budget, you can also use steel brake lines. I only have one fuel line because I use carbs. Ten years ago I bought a long truck brake line, bent it to fit and it has worked great. Since then I have bought both supply and return lines from Tangerine Racing for when I decide to go to a 3.2 six one of these days. Real soon. Maybe in a year or two. Someday.

I value Cap'n Krusty's reply, a Porsche trained mechanic, with half a century's experience. I'll leave the original nylon lines in place and replace all the rubber hoses and clamps with fuel injection rated stuff. However, I must correct the Cap'n. Per my Chinese made micrometer, the supply line is 10mm and the return is 8mm. For fraction happy Americans 3/8" and 5/16" come close enough.

My mistake, and I stand corrected. BTW, 3/8 line is NOT a good fit, just so you know. Try using a 10mm wrench on a 3/8 bolt .............. The hose we use for that is 9mm.

We use 3/8" (9.5mm) and 5/16" (7.9mm) Gates Barricade hose exclusively on fuel system work done here.
Its foolish to try and stretch a smaller size onto the fittings as was done with the original style hoses. The Barricade hose fits tightly and doesn't like to be stretched.

I replaced mine with SS. However, when I was pulling the old ones out, i discovered how tough the original lines were. There was no need to replace them. They were not brittle at all, and had many years left on them.

Roger! Great to see you posting... FYI, Roger joined up just to register for WCR this year and made it out in his great looking 912, mentioning he had a 914 in his garage that he's been "getting around to" for 13 years. Glad to see Roger posting, great guy originally from the motherland and probably still celebrating the thrashing Brazil got yesterday in the World Cup!

Chris, I bought some Barricade from you but your on line cat shows 30R9??? BTW, the Barricade product.

My supplier changed brands on me and I never bothered to update the webpage since the Barricade meets or exceeds 30R9 spec.
I now buy 250 ft rolls because I was tired of the 25 ft rolls being wound so tight it flattened out the hose.

I always think if a team of sports car engineers came up with the solution, it's going to work fairly well (except battery trays). I like both the nylon and steel. When I had my first 914 I scoured (wasted time) on the internet looking for info about Nylon 6. It's heat tolerant and probably lasts until the end of humanity unless you're pointing a torch flame on it.

I am going to put in my $.02.

I normally agree with the Cap'n, but on this I do not.

Spend the money and get a set of Tangerine racing fuel lines. It is worth it for the piece of mind they offer.

Having been the victim of a car fire that almost cost me my marriage, I won't own a 914 with the plastic fuel lines. The fire marshal that examined her car after the fire determined the high pressure side plastic line split and sprayed gasoline over the hot heat exchangers. Instant fire. Watching a car that is part of your heart and soul burn is heartbreaking. I know.

It is not much money.. but the cost to not do it could be tremendous.

Shameless plug but if your car still has fuel injection look at the Tangerine racing fuel line kit I have for sale in the classifieds. All new fuel lines, fuel elbows, clamps, etc.

Even if you don't buy mine don't cheap out and do a half-ass solution.

When it comes to brakes, tires, and fuel related components buy quality...it's only your life you are talking about!

Replace them with stainless steel from Tangerine Racing please. We don't need any more stinking carbeques.

Here are a couple of older threads on the subject:
Plastic Fuel Line Autopsy
Fuel Lines

The issue really isn't what is inside the tunnel, it is the plastic outside
the tunnel. See the Autopsy photos.

--- bill

X2

the old plastic lines get brittle as hell in the hot area below the engine - and they crack & shatter - and you WILL burn up your car if you don't get rid of them



p.s. - those of us who work on old US Iron also know that 20-some year-old (or 30 - or older) rubber lines also crack & split, especially in the engine compartment below the manifolds where they almost universally are located

My car had 36K miles and the plastic fuel lines were still flexible (at least in the middle). The original cloth covered lines broke apart easily. That said, there is no way I would put the plastic lines back in. Tangerine lines with all the correct fittings and clamps. Chris shipped very fast and the price was very reasonable. I have a second set standing by for the 6.

No one has address the later 75-76 lines that are made of a completely different material. It appears to be similar to what is being used on new cars today. I agree that early clear lines are getting brittle at this point. In tearing down parts cars the clear lines always seem to snap in the engine compartment. Any clear lines, I would replace with SS ones.

I replaced my original lines with SS a few years back. My car is a '75. After all of the doomsday predictions from the 'experts' I was quite surprised to find the lines inside the tunnel to be pristine and outside? Just a little dirty.
I like my SS lines but thay weren't necessary by any stretch...