I'm getting a small drip from one the metal fuel hoses under the front-most clamp holding it to the underbody. Which means the line probably either has a crack or a pinhole in it (wear from the clamp or corrosion). What's the best way to proceed?

Are the fuel lines from front to back available anywhere? Should I cut the offending line under the car, replace with metal brake line of appropriate diameter (avail at auto parts stores) from the damaged area forward to the motor, and use a short rubber line as a coupling?

Or should I use a flare tool to make a flared joint, which will likely be stronger/safer? What is the diameter of those fuel lines, inside and out? Is it safe to use a hacksaw to cut the line, or would that be likely to start a diesel fuel fire?

Assuming you have a 616 or 617 diesel, you can patch in as much rubbe rline as you need to with clamps. The feed line is under suction, and the return line is very low pressure.

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I'd prefer not to have a rock puncture the line, leaving me stranded or with a fire, though Presumably, it was designed with metal fuel lines for a reason.

The odds of a fire are very slim. Diesel has a rather high flash point. High enough I believe it's not even categorized as "flammable" per the definition when dealing with hazardous materials. Instead it is simply combustible i.e. it will burn under the right conditions but it's not prone to burning at ambient temps and pressures.

While not entirely scientific in nature, here is a video that demonstrates this:

https://www.youtube.com/watch?v=3LeRSPuA5Z4

It's why (for better? or worse...) there are lots of W123 diesels running around with fuel leaks from injectors, rubber lines, etc. Even under the hood, leaking on to a hot engine, diesel tends to be rather benign so people don't stress it so much.

So I'd say patching it with rubber line is a very viable solution, even if it's just to get you by until you can figure out the best way to replace the hard line.

And the odds of a rock or something else cutting in to it are really slim. Think about the rubber brake hoses that are under the car. They usually fail from age before anything else happens.

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When my car was saftied, the mechanic pointed out that I had a leak. His comment was "you're lucky its not a gas leak or I would have to fail you..." interesting that it isn't a fail point for a safety inspection around here - or maybe my mechanic was just being nice to me.

I have new fuel lines on order.

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1981 240 D in the Toronto Area
Ivory with one black fender

OK, so I pulled the clamp holding the lines to the bottom of the car off after work. There was a big gaping hole in the return line. The only thing that kept the leak from being massive in the first place was the little rubber grommet! Fuel started SQUIRTING down. Stuck a bowl under it. Fuel wouldn't STOP SQUIRTING.

This is the return line! Shouldn't that go to the top of the tank and not be able to siphon fuel from a tank that's about 50% full? Almost a gallon came out before I crimped the line on both sides of the leak and clamped a split rubber hose over the leak. No leakage, but the fuel return is blocked, so the car isn't safely drivable now.

Options:
(1) Figure out how to break the siphoning action. Can I disconnect something from the tank so that I don't have a fountain under the car?!?!?!
(2) Admit defeat. Use the drained diesel fuel for good purpose and light a match. Neighbors may object, and I've heard that diesel fuel is actually hard to ignite.
(3) Admit defeat. Have the car towed to a mechanic on Monday and let him deal with the evil thing.

Oh right, and I have a date tonight and will go smelling like a tractor mechanic who had a bad day at work. Fun times!

You crimped the metal line? Should have crimped the cigar hose and the rubber return line under the tank. PM me, I have just what you need.

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Yeah, I crimped it. I'm planning to remove the crimped section anyway, so it's not as if it's worth saving!

Where is this rubber hose under the tank that should be crimped (I crimped the cigar and this didn't staunch the flow)?

The return line does not return fuel at the top of the tank. It comes in at the bottom. The metal tube extends into the tank 3 or 4 inches.

Under the car on the passenger side, above the axle are 2 rubber hoses, one is the supply to the engine, and the other is the return.

The return will have a hose clamp on each end, and slips onto the metal line. This is the line you should clamp.

The supply is easy to recognize, where it goes into the tank is a 46mm aluminum nut on the bottom of the tank. this is the fuel strainer. Where the fuel line screws into the strainer (if it is still original) it will have a metal crimp on it. If it has been changed to regular 5/16" fuel line. The crimp is cut off and will have a hose clamp. The fitting that screws into the tank strainer is Brass and the end has barbs.


If you notice a rubber Bell shaped thing behind the L/R wheel pointing down, that is the tank vent.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

OK, pinched off the rubber return line at the tank which stopped most of the flow (there was still a little trickle, easily caught using an oil drain pan).

Then cut off about two feet of the metal fuel return line (it was only damaged under the first clamp) with a junior hacksaw, bent metal tubing to fit, used short lengths of rubber hose to couple it in.

Total time spent: about 1 hour.

PS - is diesel fuel supposed to be bright blue in color?

Purists turn away-

I have about 20 - 25 ft of rubber hose under my 240D. I think I still use the leaky steel lines as a support. The only steel still plumbed is the stem that comes off the tank and goes down to the rear subframe. Steel lines can be a right PIA if their not the first thing to go on the body after paint.

You can get heavy zip ties with a little tab that lets you open and reclose them as required. Mighty handy.

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82 Benz 240 D, Kuan Yin
12 Ford Escape 4wd

You're four times

It's hard to

more likely to

concentrate on

have an accident

two things

when you're on

at the same time.

a cell phone.

www.kiva.org It's not like there's anything wrong with feeling good, is there?

If you're going that route, why not go with nylon? You can get diesel-rated 5/16" O.D. nylon fuel lines that will fit into the existing clamps, they don't rust, and they won't be as vulnerable to damage from rocks and things as lines that are zip-tied in place. Make the repair better than original!

http://www.ebay.com/itm/NYLON-TUBING-PNEUMATIC-AIR-OIL-FUEL-LINE-5-16-O-D-100-/360207208339

bright blue? no... the only thing bright blue i know of is that startron biocide stuff

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1981 NA 300D 310k miles

Did you add some 2 cycle oil to the fuel? that will turn it a blue color.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Blue could be from the color of the light you are using. The fuel has a green tinge to it.

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