Diesel RVs: Re: [diesel_mercedes] Lower oil cooler line

With all the hulabaloo, I decided to take a look at my lines today. I noticed the fabric / rubber / plastic part of the lines were oily wet also. I am guessing (of course), that various fluids have dribbled over the years on those lines. They are under (or near) filters where diesel fluid would have dripped, the power steering pump where ATF could have dripped, and other parts where motor oil could have been deposited.

All to say, need to keep fluids away from hoses.

brian from laverne, ca
Mary (195K) Martha (280K)
1983 w123 300d's

From: "audiolaw@aol.com" <audiolaw@aol.com>
To: diesel_mercedes@yahoogroups.com
Sent: Friday, June 1, 2012 9:45 PM
Subject: Re: [diesel_mercedes] Lower oil cooler line

Trish,

Remember a little while ago, I said take a breath and regain composure? This is what happens when you do that. Oil leaking from one of the oil cooler lines can flow backward and appear to be coming from any number of places.

Be greatful that it isn't the rear seal.

My 300SD got one of its oil cooler lines cut, while I was on a road trip. YUCKY. But not fatal.

There are a couple of things to deal with here:

1) Figure out how the line got slit. It is POSSIBLE that it just aged out. But before concluding that, make sure that you have considered as many alternative possiblilities as you can. You don't want a repeat of this.

2) See if you can do a temporary patch until you can replace the hose. On mine, out on the freeway several hundred miles from home, I fashioned a patch with a piece of rubber gasket material, held in place by a hose clamp. Since I use synthetic oil, the patch wanted to slide away every time I tried to tighten the hose clamp. I probably worked at it for more than an hour. But finally got it clamped in position over the sliced spot. (Mine got sliced from contact with the power steering pulley - don't ask how I got it out of position to let that happen!)

2.a) You might try wrapping it with "emergency repair tape". There's stuff, I can't recall its brand name (Miracle Tape, or something), that is self adhesive tape made of plastic. It gets used in the film industry for all sorts of emergency repairs on hoses and pipes and cables. Clean the surface and wrap the tape starting inches away from the slit, going over the slit and on for inches. Then double back on itself for a couple of layers. Single layer is supposed to hold 900 lbs of pressure. Once on, it NEVER comes off.

3) Replace the hose when you can. There is one EXTREMELY important part of this operation. The two oil cooler hoses (one feed, one return) go down on the lower left side of the engine, where they are held to the engine, near the engine mount, by a simple bracket.

The bracket is ESSENTIAL. Do not skip it. Do not lose it. Do not leave the hoses without it, thinking, "I'll get back to is someday". The bracket keeps the hoses from beating themselves to death with engine vibration. If the previous owner left the bracket off, that's your problem. Go to the junk yard, or call Tom Hansen at the Classics Center and get the bracket before you do the job. The bracket is held on by a single bolt, if I recall.

To replace the hoses or either of them, you MUST raise the engine off of the left side motor mount. When you get the new hose, you will discover that it has metal sections and rubber sections. You MUST keep it in the shape that it comes in - DO NOT bend the metal sections.

Even if you could bend the metal sections, you couldn't fit the hose in place without lifting the engine off of the motor mount. This is an indication that the Benz engineers saw this as a low wear part, never intending it to be replaced, except in the case of accidental damage.

Lifting the engine is NOT such a big deal (remember to unbolt the motor mount and the damping shock absorber FIRST. It may sound intimidating, but it really isn't so bad.

DO NOT DO THIS JOB unless the car is up on jack stands on a very solid surface (not gravel, sand, dirt or grass).

This IS something that you can do in your garage or driveway, but will be easier if you can put the car on a lift. Once you get a good look at the hose routing, and a good view from underneath, you will see that it is actually pretty straightforward.

IF you can't find a cause for the failure, then assume that the hose "aged out" and split. THEN assume that the other hose is the same age and maybe the same condition. Since you don't want to do this job twice, get both hoses and replace them at the same time.

Cordially,

Tom

In a message dated 6/1/2012 10:25:39 A.M. Pacific Daylight Time, purrfectharmonyfarm@wifi45.com writes:

Yep that's what it is. Kevin climbed under there, wiped everything down, started it up and watched it leak. Big slit in it.

Ordered a new one from AutohauzAZ, the best price we found via a massive search. Free shipping too! Hopefully it'll ship today. When I can afford it I'll get the upper hose. The brakes are next. A/C????? Oh well. It's been 4 yrs, what's one more blistering summer in N TX without? At least I have it in the house!

-- '81 300SD
Trish Dougherty
PurrFect Harmony Farm
Ennis, TX
http:/purrfectharmonyfarm.intuitwebsites.com