W123 300D Oil cooler lines - PeachParts Mercedes-Benz Forum

Stretch · #1 03-11-2010, 02:32 PM

Dear All,

I thought I'd add this information for those who have struggled with oil cooler lines on a W123 300D.

If any of you can not remove the engine mount in order to give yourselves the necessary space to remove and replace the oil cooler pipe lines (I got stuck because I didn't have the correct size Allen wrench) here is an alternative way.

This might sound a bit mad but remove the radiator, the engine shock, and the middle (oil cooler line) mounting bracket and it is a piece of cake!

Explanation:- I discovered this solution with the radiator already out whilst replacing the front crankshaft seal.

I've included a photo looking from the front of the car towards the back with the radiator, engine shock / damper, and mounting bracket removed. And another photo of the middle oil cooler line mount.

funola · #2 03-11-2010, 05:25 PM

Nice! How long did it take you and did the lines come out and go back in without being like a puzzle? Just to be clear: you did not undo the engine mount and did not jack up the engine for clearrance and the lines came out without interference?

Carpenterman · #3 03-11-2010, 05:32 PM

Good workaround! I also read that you can take the oil cooler out. You already have the lines off and there are only two bolts to remove at the clamps.

JHZR2 · #4 03-11-2010, 06:16 PM

Getting lines out was tough, but putting back in, I had my wife help me, and I had both in within 5 minutes. It really helps to have another set of eyes and a bit of pull from uptop when feeding from below.

I would recommend replacing motor mounts when doing this though... mine had less than 10k but 6 years on them, and one was shot, the other was crooked...

Stretch · #5 03-12-2010, 09:00 AM

Quote:

Originally Posted by funola

Nice! How long did it take you and did the lines come out and go back in without being like a puzzle? Just to be clear: you did not undo the engine mount and did not jack up the engine for clearrance and the lines came out without interference?

Well how long did it take? With the radiator (and oil cooler attached) already out about 20 to 30 minutes!

I did not jack up anything - and I did not have to touch the engine mounts at all.

So say that the lines came out without interference is more or less correct:- You need to pull the lines at the front of the car up in the air to clear the engine mount obstruction... sort of going round the bend.
I think the trick is that with the middle mount gone and the damper too you've got enough jiggle space to get the lines out with out scraping stuff off of your engine bay or your fingers.

Stretch · #6 03-12-2010, 09:02 AM

Quote:

Originally Posted by Carpenterman

Good workaround! I also read that you can take the oil cooler out. You already have the lines off and there are only two bolts to remove at the clamps.

Indeed there are only two little bolts that hold the oil cooler in place. You might be able to get the oil cooler lines out by just removing this part and leaving the radiator in but I think there is a better chance that you'll damage the delicate fins on your radiator whilst you jiggle the oil cooler lines free...

Stretch · #7 03-12-2010, 09:07 AM

Another tip that may help is that I found quite important to fit the new cooler lines to the filter housing - doing up the nuts hand tight - so you can still rotate the cooler lines into the correct position for the mounting brackets.

Doing it this way round (rather than attaching the mounts first) means that you will probably get a really good seal at the joints and you won't have to force the cooler lines into position. The previous owner / mechanic who had fitted the previous lines on my car had tightened the top line so hard that it was twisted... this must have restricted the flow of oil to the cooler.

funola · #8 03-12-2010, 10:41 AM

Hi Army,
You're in the Netherlands. Do you have a Euro model btw? Does it have AC or cruise. Those components may add complications to oil cooler lines r&r in a 300D. Some model/years the oil cooler lines are wide open and other model/ years they're buried.

rs899 · #9 03-12-2010, 10:46 AM

uh, yeah...I don't see an A/C compressor

Stretch · #10 03-12-2010, 01:39 PM

Quote:

Originally Posted by funola

Hi Army,
You're in the Netherlands. Do you have a Euro model btw? Does it have AC or cruise. Those components may add complications to oil cooler lines r&r in a 300D. Some model/years the oil cooler lines are wide open and other model/ years they're buried.

Ah ha - that might make it more complicated for others...

I don't have AC or cruise control and yes it is a Euro model.

HOWEVER - looking at the picture of a removed OM617 engine and ancillaries in my Haynes manual it does not seem that the AC compressor would get in the way as it sits below the cooler lines at the front of the engine (in this picture anyway). I assume the cruise control unit is just above the engine shock mount (the one on the engine). I don't think this would be in the way either:-

My method was to undo the connectors at the oil filter housing - remove the shock and the bracket that holds the middle clamp. This allows the cooler lines to fall downwards and slightly forwards and then allow you to sort of hook (round the bend) the cooler lines free.

I had another look at the car today and I reckon (on my car anyway) you could probably get the cooler lines in and out without removing the radiator - but I'd recommend covering the radiator with a bit of cardboard or something to stop any unwanted damage.

stapletron · #11 09-23-2010, 10:44 AM

Hi all,
Just wanted to share a little of my experience using the remove radiator method. I have a 1984 300D with AC and cruise, and the compressor does get in the way. The large mount on the back of the compressor doesn't let you move the lines upward enough. But unbolting and dropping the compressor and mount give plenty of space. My lines came out nice and easy, but I ran out of daylight so today I am putting it all back together. All in all, I'd say this is a good alternative method. Thanks for the advice!

Stretch · #12 09-23-2010, 03:03 PM

Quote:

Originally Posted by stapletron

Hi all,
Just wanted to share a little of my experience using the remove radiator method. I have a 1984 300D with AC and cruise, and the compressor does get in the way. The large mount on the back of the compressor doesn't let you move the lines upward enough. But unbolting and dropping the compressor and mount give plenty of space. My lines came out nice and easy, but I ran out of daylight so today I am putting it all back together. All in all, I'd say this is a good alternative method. Thanks for the advice!

You're welcome - and welcome to the forum. I don't suppose you took a photograph of what you did? I'm sure others would like to see it done on a car with more options that mine!

Stretch · #13 02-26-2011, 04:29 PM

Like the title says - I still think getting out these oil cooler lines can be a lot easier than jacking up engine mounts etc etc etc

From the pictures in my Haynes manual (yes I know - not always a reliable source of information) removing the oil cooler lines' mounting bracket that is closest to the engine mount still looks like it will give enough room to remove the lines even with more options fitted to the engine...

Take a look at this picture:-

I know this isn't the normal orientation but if you

1) disconnect the bracket at the front from the oil cooler lines (you don't need to take this one out)

2) Unscrew the oil cooler lines from the oil cooler and the filter housing

3) Take out the engine shock

4) Take out the bracket that holds the oil cooler lines - this is the one that is positioned close to the engine mount

It looks like this:-

5) Wiggle the oil cooler lines at the front upwards and hook the lines around the engine mount (if you want more space take out the radiator - or perhaps just the oil cooler if it will disconnect easily)

I'm pretty sure that's a job done!

If someone with more options on their car tries it this way I'd be interested to hear how you get on.

Prove me wrong - no hard feelings - honest gov!

katubma1 · #14 05-03-2011, 03:33 PM

It may be a little un-traditional, but on my buddies 300d, to get the leaking oil cooler line out, I just cut it in the middle so both parts can be dropped out, and then had the hose company flare on a fitting to re-join the two parts...