fuel hose OEM Mercedes or aftermarket?

[merrill]

while under the car this weekend working on removing the rear axle I noticed fuel seeping from the braided hose from
the tank to the fuel pump.

i have replaced this line twice in 14 years with the oem braided line which is probably a decent life.

anyone have experience with aftermarket hose vs oem?

thanks  in advance

[wwheeler]

While twice in 14 years isn't bad, I would think you should get a little better life from a fuel hose. I can see replacing them as a matter of maintenance every ten years, but I don't think it should fail that quickly. If you are using pump gas with ethanol, maybe the hose material is not totally compatible with ethanol. I am familiar with examining rubber materials that fail very gradually with incompatibility, and your time frame sounds about right. Again not an urgent issue, but I would expect a bit longer life.   

[Benz Dr.]

I've seen this hose fail before when few others do on such a regular basis. You can remove the hose, cut the rubber portion away, and then replace it with regular fuel hose which will last a lot longer.

[ja17]

Also, I think new supplies of this hose (from Mercedes) are made from improved materials. Try to avoid new old stock hoses.

[Shvegel]

Cohline is the factory supplier of the fuel lines.  I accidentally bought the same hose from Cohline and Mercedes genuine and they are literally the same hose, same markings etc.  I have some pictures buried in my phone that I will try to dig up.

[Shvegel]

Found it. One of these is Cohline from eBay and one is Mercedes factory.  The only difference is the price.

[ja17]

Notice that the hose material is changed from the original fabric covered hose. This material most likely will resist degradation from modern fuel formulas.

[merrill]

well got around to replacing the fuel line today, every time the line was touched it would seep fuel

both ends had cracks (photos) but the tank end was the worst.

replacement line from the local auto shop fit perfect.  lets see how long it lasts

[wwheeler]

Oh wow! That is really bad. You definitely want to make sure it is rated for fuel and is not an old hose stock. For gasoline, Nitrile (Buna/NBR) is the best rubber but it has horrible ozone/UV resistance. So if you use old hose stock, the ozone and UV will have attacked it prior making it prone to cracking when exposed to fuel.

[merrill]

hi Walter,
i think this line will work fine

Gates 3225 series
   
This small-diameter multi-purpose hose is designed for fuel circuits (leaded and unleaded petrol, diesel). Recommended for clamped hose applications on all fuel systems, including fuel injection systems.

Key Features and Benefits:
• Cover resists heat, oil, ozone and weathering with spiral textile reinforment
• Tube has been upgraded to meet changes in fuel characteristics and resists  heat and oil
• Working pressure up to 1 MPa (10 kg/cm²)
• Temperature range from -35°C to +125°C
• Meets requirements of SAE J30R7 and DIN  73379 (except for tolerances)

[wwheeler]

Looks good. The hose says "not for injection systems" but I am sure that has all to do with pressure limitations and not compatibility with fuel. 1 MPa is equal to 145psi which isn't a high pressure hose but perfect for our fuel systems. 

[merrill]

this may also explain why i was getting poor fuel economy. 

[85lc]

There is a 11mm and 8 mm hose from the fuel tank to the pump. 
Do these hoses to and from the tank need to be injector rated?  I would think that the pressure is fairly low.  The tank is not a high pressure tank.

[Cees Klumper]

Low pressure I would think.

[ja17]

Today's "injected rated hoses" must be able to handle very high fuel pressure (possibly 60 to 90psi or more), compared to a pagoda's fuel pressure (usually less than 20psi never over 30psi). Always look for the exact pressure rating of the hose to make sure. Most non-injection fuel lines these days are rated over 30psi. With a pagoda, the large line coming out of the tank is gravity fed to the electric feed pump, and has basically no pressure. After the electric pump all fuel lines must have the potential to deal with 30 psi. Why 30 psi? Well, if the return fuel line going to the tank gets blocked then the electric fuel pump, in your pagoda, will over-pressurize the fuel system to it's maximum out-put which can be just under 30 psi. Under normal circumstances fuel flows back to the tank and pressure is maintained  around 12-15psi by the return fitting orifice or check-valve on the injection pump.

[85lc]

There is a fuel hose with a swaged "L" connection that connects to the fuel pump and runs to the fuel line running forward to the fuel filter.  The fuel line OD is 10mm.  I bought what I thought was this fuel hose and its ID is 9mm & not 10mm to fit the fuel line.

Has anyone had this problem?

Does anyone know what the correct part number is for this fuel hose.  Is it 111-470-09-26?