I've noticed that my rubber return fuel hose (from the fuel filter canister to the steel return fuel line to the tank) ballons from 3/8" (ID) to about 5/8"(ID) (for about 8") then goes back to 3/8"(ID) where it attaches to the steel line (616 engine 75' 240D). It has developed cracks and I want to replace it.

Does any see any problems if I replace it with straight 3/8" rubber fuel line? I assumed that the larger balloned section is designed to absorb pulsating shocks from the injector pump. I'm worred that if I use straight 3/8" hose that it may put stress on the fuel return lines that tie the injectors causing them to either leak or come off.

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87 300SDL (115,000mi. 7/1/2008)
03 Jetta Wagon TDI (62,000mi. 7/1/2008)
75 240D(sold, sad to sell it, needed the garage for the SDL!)

Smokey

It is called a cigar hose. There is a reason it is make this way. I just don't know it. I use it but have a friend that just used a straight hose. Charlie

You're right Smokey,it's to absorb the pulses.

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Democracy dies in darkness, you have to kick at the darkness till it bleeds daylight

Smokey,

Cracks, so what? As long as it doesn't leak why replace it? Its nothing that will cause the car to stop running.

The worse thing it can do is start to leak and then you can replace it. Keep a replacement regular hose in the trunk, but I doubt if it will even leak because there is no pressure on it.

If it ain't broke, don't fix it!

P E H

To keep from having it start leaking a thousand miles from home on a Sunday in the middle of a family vacation ?

Leathermang,

That's why I told him to carry a piece of tubing along as a spare. THe "cigar hose" will start to seep slowly for a long time before it has a serious leak because there is practically no pressure on it. If car owners replaced every part that might fail, they might as well get a completely new car because the replacement process would never end.

We MB owners trust MB to give us cars that are very reliable and don't need a lot of parts replacement. Otherwise we might as well drive a Chevy or Ford.

P E H

So you just lump everything into one category ? No provisions for 1. rubber items 2. that can be seen to be cracking 3. That carry fuel ?

People new to the forum should understand that PEH is exceptionally "frugal"....by his own admissions and the examples he has given in the past of his careful money management...

Ahem. I read this web site because:
1. People help each other in a friendly (and humerous) manner.
2. People here have helped me with my car without even knowing it. I was so new to the internet that people had to show me how to log in and use the search feature.
3. People choose to respect each other, even if they disagree with the help offered.

By the way, I'm not frugal. I'm cheap. But I keep my old belts and hose elements in a box in the trunk. The little hose elements fit inside the big radiator hoses, so they don't really take much room. Never had to change one on the road because I change the belts and radiator hoses every two years, and the little hose elements every five years (coolant and fuel). It's comforting to me to know I have insurance in case debris or a critter gets a hose on the road.

Hoses do deteriorate from the inside, so it's a good idea to replace all the hose elements periodically. Most people forget to consider the brake and fuel lines. Good job, Smokey. Peace of mind is pretty cheap when you buy the parts here (they also give us this web site for free).

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daBenz - 1970 220D

If your keep your extra belts and hoses in the trunk. You may want to try and place them around the spare tire they are out of the way but ready when you need them.
I for one like to keep the car leak free and clean. That way if I get new leaks I can see them.
To me the money I spend on belts and hoses are cheaper than a tow to a shop. Just my .02 worth. Charlie

I replaced mine about 20K ago with a piece of straight rubber hose before I realized that it was designed to absorb pulsations. I haven’t had a problem but I do plan to put a new cigar hose back in the next time I’m ordering parts and doing anything with the fuel line. It’s on the return side and if you park the car pointing downhill you won’t get air in the line. You have to do it quick while the fuel leaks out is all.

JohnM 1983 240D 4sp 154K

Thanks for the feedback.

I was running diesel purge through the engine and noticed cracks in the "cigar" hose. Couldn't find a replacement "cigar" hose on Fastline but they may have one for newer models. The one on the 75' 240D is about 10" long. I would assume it's about the same length on the newer 240D's. I'll do some searching.

BTW, the diesel purge worked great! but as soon as I started running the remaining fuel in the tank the engine started smoking and knocking again. I think I have a bad load of diesel! I'm goiing to try some diesel additive.

Thanks!

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87 300SDL (115,000mi. 7/1/2008)
03 Jetta Wagon TDI (62,000mi. 7/1/2008)
75 240D(sold, sad to sell it, needed the garage for the SDL!)

Smokey

JohnM,

Who cares it you get air in the return line. It will just go to the fuel tank with the rest of the air in he tank just like it does when the sysytem self bleeds the air off when you put in new filters.

P E H

My driveway is sloped quite a bit. If I have the car pointed uphill and I work on the fuel line, it seems to me that air is drawn backwards and introduced into the fuel supply system. Maybe not or maybe not much, but to be safe I point the car downhill. I am aware that air in the return line itself isn’t an issue.

JohnM 1983 240D 4sp 154K

I was told that air in the return line would rapidly expand until the entire car exploded!

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Dave
1995 C280
1999 Triumph Daytona 955I - my speed fix.
1982 300TD - Gone, but not forgotten.