85 300D transmission cooler lines
 

Does anyone have a part number for the passenger side auto trans cooler metal line for an '85 w123? Mine has been brazed previously, and when I tried to replace the rubber hose to the cooler, it was seized so bad that I managed to snap a 17mm line wrench.

Alternative question: has anyone made one of these lines yourself and happen to know the dimensions and fittings I need?

wow. broke a wrench?

You could get a hydraulic shop to do it.

All the info you need is on the other line.

I might take it to a shop. Would probably be easier than trying to DIY it.
Yeah. Though now that I think about it, I think it was a HF set. I didnt break it in half, one of the jaws snapped off. Probably a good excuse to buy a better quality set.

I just replaced one myself.

there are many variants out there. I tried to bend one into shape to make it line up... worked... but it was a shorter line. SOB. needed a custom rubber hose made.

I agree.... this is a tough one to DIY unless youre good at brazing ends and have the right radius bending tools.

Cant just leave the line on there? leaking? what about having a shop fix whats there?

The rubber hoses are in pretty bad shape. I can leave the line in place as-is, but I would feel better having a new hose and line to protect the transmission (not to mention one of my friends nearly wrecked when a transmission line failed on his car).

I soaked the fitting with penetrating fluid and will have to get a new set of line wrenches and see if they will come loose after a day or two. I rounded the brazed fitting off a bit, so I may be stuck unless I can replace the entire line.

This is the second car I have had problems with those fittings on. I wonder why that is? Maybe corrosion since they are so close to the ground.

Are they NLA from dealerships?

I am guessing they are not easily obtainable.

But the w201 190e / d used this trans and I bet theres plenty out there. You would have to modify them most likely. But the ends would be correct.

'85 w123 is the only year that will have the same ends. 722.4 trans.

85 SD will be different than w123, but will have the same ends.

if you have a backup car... maybe try slicing the nut of the rubber hose down 2 sides.

Hitting the threads a little bit would not be a big deal, the seal is at the flare fitting. threads are just for holding it.

Hmm, mine is an early 85, I have the 722.3 transmission I think.
Thats a good idea. I might try that. Though honesyly I will probably just wait until I can get a proper set of hoses. The car should be drivable anyway, the hoses will last a while. Or I might try a bit of heat and more penetrating fluid.
I do have a backup car, but the 300d has been off the road for a couple months due to heat and HVAC & power window problems that will hopefully be resolved this weekend

Try: 123 270 40 96 & 123 270 33 96

I got these from here:
Mercedes-Benz Teilekatalog (Ersatzteile online)
#802 and #803

You can leave the Lines in place and you grind or file off the crimped section n collars on the original hoses and pry them off with a screwdriver and pull off the old Hose. After that you can go down to Autozone or a similar place and get some Oil Cooler Hose and hose clamps and replace the old hose with them.

Another advantage of the above is if the Hose Fitting is corroded on to the Radiator side you are not going to damage the radiator trying to unscrew them.

The same method and idea is in this thread. Your transmission cooler Line crimped section is not as tough as the one shown.
Repair your leaking oil cooler lines! (Pics fixed) - S-10 Forum

I see what you're saying there. That would work. I ordered some higher quality line wrenches and some odd designed vice grips that are specifically made for gripping hex bolts/heads, I might try those again - or I may pull the hardline off of the car, clamp the fixed portion in my bench vice with some aluminum padding, then try to break it loose with a box end wrench on the rubber side of the hose.

it would be wiser to let the sleeping dogs lie,

cut the rubber cooler hose and use a small dremel to cut the crimps away, peel off the hose from the barbs.

use some trans cooler hose and clamps to tighten the hose in place - they are not under great pressure. You can use this same hose to repair your metal line too.

I support this also. very reasonable solution.

That is a safety concern to me. I have seen what happens if the line slips if the fitting slips, and I doubt the barbs are designed to hold off just a line clamp. I would rather spend the $150 or so on a new hose if needed than worry about it.

I am using the hose and clamp on the rubber lines since quite a while now. And I have also succesfully repaired metal cooler lines on power steerings on W body chevy sedans - cut the metal line, use a double flare tool to make a barb, slip on hose tighten with clamps - never a leak.

The safety here is the bulge you make with the flare tool on the metal line.

you can choose to use fuel injection hose band clamps.

The ATX cooler line rubber hose repair is pretty commonplace too. But your car, your choice.. we just gather here to tell of our own repair and procedures.