Fuel lines

ER Classics Desktop 2022

It was a Jaguar XJ V12 with Lucas injection. In front of a traffic light the driver smelled gasoline-like… We're not gonna be kidding about Lucas. The brand was so neo liberally wrung by its clients that they could guarantee delivery, but not quality. And even that in moderation. We are simply talking about a classic with everything that surrounds it. Likewise problems with the fuel system.

Despite the fact that the current fuels mainly consist of excise duties, they still do a good job in terms of combustibility. Often no longer in the way that petrol used to smell so good and the factory data on ignition time is still like the workshop manuals, but still.

Much suffering unnoticed

A garage owner who has silently specialized in classics has kept track of the fact that in three quarters of the customer cars that come to him for the first time, things are not in order during the fuel route. This often concerns just 'worn out' or outdated fuel hoses. And just as often he wonders why that classic has not already gone ablaze.

Hoses age, harden, become porous or crack

Hose clamps will rust. A fuel pump is a wearing part, just like a water pump. If you're lucky enough and have a classic that just breathes in through a carburettor - or as many carburettors as you can think of - then you have an advantage. That whole stuff is usually clearly visible and reasonably accessible when you open the hood. Fuel pumps, on the other hand, are usually mounted somewhat hidden. The car will have to be on the bridge to gain insight into this.

With injectors there is a good chance that the injection pipe and hoses are on top of the block. The thermal load there is unfavorable. The probability of ignition in the event of leakage is optimal. Optically these snakes often look even better than they are. The approaching infarction or aneurysm only reveals itself when the tube is cut open.

Take a good look first

Of course, the whole thing starts with the visual inspection of the hoses and the mounting clamps. Keep in mind that the pipework under the hood is exposed to possible greasy contamination and aging due to the varying thermal load. The suspension and mounting points of the pipework must also be checked. And assume under the car that the case there is already suspect if there is a layer of tectyl on it.
There is usually also a filter in the tank. The associated O-ring is also a point of attention. Just like the fuel return line.

Fuel accumulators and fuel filters are also items that require regular replacement. The composition of gasoline is, as we already noted, very different from the days when we still put tigers in our tanks with impunity. Not only has that changed the smell. The stuff that nowadays includes a hefty dose of acetone - nail polish remover! - exists is also 'thinner' or 'leaner'. This increases the risk of internal leakage in the high pressure part of the system. In turn, internal leaks can cause fuel to get into the engine oil.

As a result, that lubricant loses a serious part of its lubricating effect

So if you notice that the oil level in the crankcase has risen while checking the oil, it is not a cause for joy. Give the dipstick a sniff or hold a lighter flame at the tip of it. If the oil then starts to burn splatteringly, then there is a problem. There are people who say that ethanol killer gives modern gasoline the right juiciness again. We are still looking into that.




Give a reaction
  1. Carburettor shafts also tend to leak. My first car was not really economical (Kadett-D1.2S) but predictable in terms of consumption, every 400km refueling with a little margin. So I thought: Baarle-Nassau where I was on my way I will get anyway because there (Belgian part) was / is cheaper refueling. However, at 380-390km a splash and come to a standstill .. empty tank. Luckily there was a farmer close by who had a jerry can Euro 95 (which Kadett drove on for a while) and I made it to the gas station. But once at the garage where I had the car serviced, they said I was lucky. Petrol leaked through an ash on the exhaust manifold, which could have resulted in a fire. All this time I had smelled nothing.

  2. Last year I bought new E10 resistant fuel hoses in a car shop. These are sold per running meter. Nowhere or the hoses is stated that they are alcohol resistant. You just have to trust the shopkeeper on his beautiful eyes. That doesn't make me feel good.
    As long as I can, I will drive alcohol-free. I don't drink alcohol and the car doesn't drink alcohol ..

  3. Never had any problems with fuel hoses made in Japan, since 1981 from Honda placed on all my European cars and motorcycles without surprises of leakage and not resistant to alcohol etc., also have no fraying casing, was fitted internally at Honda per model, but also on roll available, the strange thing is that this quality is still not available through the car material trade!

  4. There can be (too) many causes of fire. My built Cobra427 with 7 liter Ford V8 picked up a piece of wood at 130 on the highway (slap) in Belgium. Was pushed up by the crankshaft pulley / belt and squeezed between dynamo and inner shield (short rattle) and then either the fuel pressure regulator hit the firewall or the only piece of rubber hose running from there molten to the thick Holley. In any case, with the sturdy electric racing pump in the back, leaded super was sprayed on the manifolds at the time and the Jos Verstappen effect was immediately there at 130 ...
    Well, there was not much to do about it, except perhaps also a cage around fuel pressure regulator or similar (there was already stainless steel lining around the rubber pipe).

    Also important: practice in the dark whether you can quickly get out of your (here harness) belts and preferably do not wear a plastic jacket, as it will melt right on your skin. Fortunately I was wearing a thick leather jacket which protected me nicely with my arm in front of my head and my left breathing and came out well, but the fire was a la second through the “cabin” and over the window at 130 and I still had to come to a halt. Which also turned out to be a real party with the same half-burnt tire and rim right rear 🙂 Luckily not too burnt, could have been so different.
    Ps. polyester burns away really shockingly fast, at least with a steel body you have some left over.
    This was a typical case of “10 years of building and burning for 10 seconds” and everything is gone. Fortunately, a few more years of lawsuits against the insurer to kick the habit, because they would like to receive your tokens, but not really pay out at all costs.
    By the way, that detox did not work, still miss that thing enormously. But yes, life sometimes takes weird unforeseen turns. So does anyone know another suitable V8 Cobra project, I'd love to hear about it. And no, never through a certain dealer in Belgium ...

  5. My Triumph TR250 politely thought that failure is better after the ride than during. When I opened the garage door in the morning, the entire floor was covered with a thin layer of gasoline. The wonderful smell of petrol fumes was unbearable! The freshly filled tank had emptied through a crack in a connecting hose in the fuel line.
    Tip number 1: don't try to start the car when the garage is full of gasoline.
    PS the car has now been completely restored and has new pipes!

  6. From what I read, acetone (CH3COCH3) is added in small amounts that reduce emissions and make the engine run smoother.

  7. Although neither are fine substances, I would not want to create the confusion to call the Ethanol used in gasoline Acetone, may sound nice, but it is not. Acetone is an organic compound while Ethanol is pure alcohol, so Ethanol is added to the gasoline and not acetone

    • Both Ethanol and Acetone are organic compounds. Organic compounds have the similarity that they all have carbon as a basis, in combination with mostly hydrogen. Oxygen is sometimes also attached to it and with Ethanol in the form of -OH (oxygen-hydrogen). Acetone has = O (oxygen doubly bonded to carbon). Acetone consists of 3 carbon atoms, 6 hydrogen atoms and 1 oxygen. Ethanol consists of 2 carbon, 6 hydrogen and 1 oxygen. In addition, Ethanol is one of the many alcohols. Methanol is also an alcohol, but so is IsoPropylAlcohol, for example.

  8. Hi Dolf, Interesting and fun article. Indeed, Lucas did not have a good reputation. And that they were forced to be neo-liberal (examples too many) prompts me to consider the following.
    Regards, Jeroen.

    Rubbers up to date is important to prevent all kinds of malice. This is still possible for hoses, but it is more difficult for other gaskets (inside the system). Therefore:
    - Can you (classically) also include in the research or adding a dash of 2T oil in the tank to make the current Otto fuel (gasoline is hardly to be called) less lean and less sensitive to oxidation. I now gamble at the start of winter storage: especially “in hope of blessing”.
    - There are (admittedly laborious but workable) methods for removing Ethanol.
    See ao . Is that enough or does more need to be done (for example also removing the acetone)?

    And to end positively the following. I notice that with my classic cars I spend much longer with exhausts and stuff than I used to. Or: the iron is better. Or: the exhaust gas is less aggressive or, for example, less humid. Who knows may say.

  9. Hello Dolf, just bought a 504 coupe with indeed a German Kugelfischer fuel system. Was planning to thoroughly inspect the entire system from back to front soon and replace the necessary. I have already lost a Vitesse once due to fire with presumably a fuel leak in combination with a hot exhaust manifold and the Vitesse on fire. Someone from a newspaper took a photo of it, but I never found it, nor the person the photo. The disaster took place from Velperbroek in the direction of Rheden, I think 2005.

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