Fuel hose "saturating through"

[Peter van Es]

When driving today I was warned by a passing motorcyclist that my car appeared to be leaking fuel. When I had a look, the braided fuel hose that connects the pump to the fuel line leading to the engine was completely saturated and leaking fuel through it everywhere.

Not just at the fuel line (the clamp is still attached properly), and not at the fuel pump end, but all the way through. When I switched off the car (and the fuel pump) the hose is fully saturated with fuel everywhere.

Will just replacing this hose be sufficient? Or is there a deeper cause for this to happen that I should be investigating?

The weird thing is, the hose looks new (especially the metal end that connects to the pump) and has been replaced in 2007.

Peter

[Jonny B]

Perhaps an autopsy, or hose-opsy (?) would be in order, to see if there was some flaw in the connections or some small cracks in the inner structure. I would not expect a hose replaced ini 2007 to have an issue so quickly.

[dtuttle123]

Peter - the very same thing happened to me about 2 months ago - more of a progessive leak over a few weeks - but just like you describe. 

I had the hose replaced, and it hasn't presented any more problems or leaks.  I don't think my hoses were that old  - maybe 3-4 years.  Not sure why the breakdown of the material?  Maybe more ethanol in the fuel?

When it started to leak badly, I had my car flatbedded to my service guy for repair - didn't want to take a chance.

[jameshoward]

The fuel hose protective sleeve is fibrous material therefore a leak in the hose would spread quickly throughout the fibers. I replaced a perished hose a few years ago. I don't think at that age yours would be in such a poor state. Perhaps it's simply a hole in the hose, or perhaps it's been pinched by a clamp. I think it would be sufficient to replace the hose and observe. Once you have the old hose off you may wish to remove the fiber sleeve to identify the problem. Probably worth looking at the other hoses whilst you're there. It's a crappy job to do; have someone stood by with a powder extinguisher and a tray of spill sorb to hand. You'll be familiar, I am sure, with the golf tee trick. Works very well.

I'd be interested to know what your investigations show.

[graphic66]

I think it is the ethanol in the fuel eating up the hoses, I have seen several old fuel lines lately acting like that.

[ja17]

Hello Peter,

Yes, quite a common problem these days.  I think it is the fuel. Hopefully new hoses from MB are new modern material and not old stock.  The fabric hides the real condition of the rubber until it is too late.

In a pinch you can cut the metal crimp off the fittings, re-use the fittings and clamp a new stock hose in place of the fabric braided hose.  Use a hack saw or cutting disc to make a diagonal cut through the metal crimp on the fitting and peel the metal off.  The old hose will then slide off the fitting leaving a  good clamping surface for a new hose. 

A good section of fuel injection hose from your local auto parts store will most likely be made  from modern matierilal which stand up to the modern fuels.  Use fuel hose rated at 50 psi or greater.

[Peter van Es]

Thanks for your answers. At least there's some comfort in knowing I'm not the only one. I just hate having to take the hassle of flatbedding the car to my repair shop... but then again, driving with fuel leaking is not much fun either.

As it happens, I have an (almost) full fuel tank. And with my jack and jackstands, the area to work on is pretty inconvenient from an access point of view. Replacing that fuel line does not look like so much work, and it's a pretty inexpensive part... but I'm concerned about how much fuel might come through the fuel pump even if it is not running.

Any further DIY or Don't DIY recommendations?

Peter

[graphic66]

Just crimp off the rubber line coming from the fuel tank with some vice grips to gently squeeze the fuel line so as not to flow while your working.

[RickM]

Peter, Is there Ethanol in the fuel where you live?

I agree with the fabric jacket hiding the true condition of the interior hose. With age a crack may go unseen for quite a while.

Be careful with the vice grips, if too tight you'll damage another hose (I use locking forceps).
You may want to use a catch pan and an old rag when pulling the damaged hose off. What doesn't make it in the pan will be absorbed by the rag/towel in your hand.
 
In order to take delivery on my '71 I had to do this very same repair in the seller's garage.

[jameshoward]

A pan with spill sorb will keep you safe, but you'll need to watch vapours, hence the recommendation for an extinguisher. It's a bit messy but a relatively simple DIY job. Earth the car with an earthing lead (a jump lead to a metal spike from the car will be fine). Disconnect the battery. Well ventalated area. Battery operated lights where needed, not mains. Rehearse the operation to avoid loosing too much fuel, I'd suggest. But you'll need spill sorb and a good pan to catch the fuel.

[glenn]

Just another 'advantage' of ethanol fuels!. ..  A long list- absorbs water vapor into your fuel and fills the carb with water-great fun in the middle of the lake.  Thank you, Kansas.

[menesesjesse]

I live n the DC area andI have encountered leaking with new oem braided hoses more then once over the last 2 years.  I switched over to a fuel injection hose 7/16 and used a high quality clamp.  The problem has seemed to go away for now. I hope forever.

[Peter van Es]

Thanks all. Replacement part on order. Will exercise due caution. If I die, who will step up to maintaining the website and taking over presidency?

Peter

[glenn]

'Replacement' hose is available.  There is no available 'van Es' replacement. ..

Please stick around. ..

[jameshoward]

Thanks all. Replacement part on order. Will exercise due caution. If I die, who will step up to maintaining the website and taking over presidency?

Peter

You're right. It's a risk. Perhaps you should wait until after the European Event, that way we'll all be safe!

[Benz Dr.]

Who knows Peter.  It could be me. That should be incentive enough to stay alive for a while. I wouldn't run the site though......

  Fuel hose problem is not from ethanol. It's simply a fuel hose problem that happens to some of these older parts. 190SL's have the same problem with the hose that runs between the fuel filter and fuel pump. In that case it developes vacuum leaks but it's still the same break down in material. Other hoses MB makes are not affected at all so it's the hose not the fuel.
 
I had the same problems with certain hoses long before the fuel was changed.

[Peter van Es]

Wow, I'm touched at all your concerns for my well-being   or should that be: Your concerns for:

• continuation of the website
• continuation of the European Event

At least the Dr is prepared to step up to the plate as President... hey Dan, only a small election to win there!

I'll try to stay alive to finalise the European Event... it really will be a good event with great driving and great people, good food and fun...

I'm trying to fix my car this saturday!

Peter

[Benz Dr.]

Hummmmm....... I don't know Peter. The place would look so different some wouldn't be able to recognise it. 

[Peter van Es]

Today successfully replaced fuel hose. New part is installed. Only a small amount of fuel, still in the hose, came out. No more leaks. I'm unharmed!

See attached picture for the old fuel hose. These cracks are only about 5-7 mm deep. I presume I can cut off the end and then re-use? Ot is the rest of the hose brittle too?

Peter

[jacovdw]

Peter,

Based on your photo, I would not cut off the end and reuse that hose at all.
Not safe as you can only speculate as to the condition of the rest of the hose under the braiding.

[jameshoward]

Today successfully replaced fuel hose. New part is installed. Only a small amount of fuel, still in the hose, came out. No more leaks. I'm unharmed!

See attached picture for the old fuel hose. These cracks are only about 5-7 mm deep. I presume I can cut off the end and then re-use? Ot is the rest of the hose brittle too?

Peter

You're not serious, surely?!

Bin the lot and get a new hose. Check the others whilst you're at it.

[JimVillers]

Peter .... This should be a reason for you to replace ALL old hoses in the car.  Include the hose from the tank to the pump and the hose from the return line to the tank.  If you haven't replaced the brake hoses, power steering hoses and other fuel hoses, I would put them on your project list.

[Peter van Es]

The point (and hence the joke) was that ALL my hoses everywhere were replaced in 2007 and only this one bled through. But as you can see from the posts, I'm not the only one. I checked all other hoses.

Peter

[graphic66]

Contrary to our resident curmdgen ethanol does attack rubber and plastic parts, Hagerty has some info http://www.hagerty.com/ethanol/faq.aspx  I have been seeing a lot of melted rubber inside fuel lines in the last few years, probably the ethanol. I believe you can find fuel stations not using it if you look. Also you can get Type A-1 marine fuel hose that is alcohol resistant.

[Peter van Es]

Thanks, good info. The fuel I use has no Ethanol. However, those attending the European Event in France should be reminded not to buy the E10 fuel (see this message: http://www.sl113.org/forums/index.php?topic=11150.msg74455#msg74455) as it has too much Bio-ethanol. Buy the Superplus 98 instead.

Peter