How do you get oil residue out of the coolant reservoir? - PeachParts Mercedes-Benz Forum

WNC123 · #1 11-10-2011, 07:15 PM

'85 300TD wagon.
While doing a full coolant flush I noticed that my (original) coolant reservoir tank is not only old looking, but beginning to develop cracks. It is not leaking at this time, but I am not expecting it to make it through the winter.
I pulled a very nice (practically new) MB reservoir out of a car in a junkyard. The only real issue with it is that there is oil residue coating the inside of the tank.
I have tried to clean it with the following products (diluted) by putting them in the tank, adding water, shaking, flushing, even letting it sit overnight full of water/cleaner:
-Totally Awesome
-Dawn dish soap
-vinegar

The amount of slime inside has diminished, but there is still a lot of residue left.
Can anyone recommend something that might clean it a little better, or completely? I do not want to damage the tank or any o-rings (obviously). I was thinking of trying Simple Green next.
I can't spend the ~$50 on a new tank and plug at this time. I also don't want to install this one and have it cause problems or ruin my new coolant.
Thanks for any input.
Jon

79Mercy · #2 11-10-2011, 07:28 PM

idk, maybe try boiling it in soapy water

tangofox007 · #3 11-10-2011, 07:31 PM

I had the same problem. I half-filled the bottle with a surfactant-type cleaner and taped it to a vibratory parts cleaner for a couple of hours.

Diesel911 · #4 11-10-2011, 07:45 PM

Maybe Purple Power or Simple Green would work.

vstech · #5 11-10-2011, 07:54 PM

I'm thinking a solution of gojo in hot water and lots of shaking...

ah-kay · #6 11-10-2011, 07:59 PM

Use a good quality detergent, oil removal agent etc, plus some marbles and give it a good shake. Some industrial system uses marbles/ball bearings to clean stuffs.

Give it a try. Nothing to lose.

tangofox007 · #7 11-10-2011, 08:19 PM

Quote:

Originally Posted by ah-kay

Use a good quality detergent, oil removal agent etc, plus some marbles and give it a good shake. Some industrial system uses marbles/ball bearings to clean stuffs.

Marbles won't get very far in the new-style, compartmented bottles.

ah-kay · #8 11-10-2011, 08:32 PM

Quote:

Originally Posted by tangofox007

Marbles won't get very far in the new-style, compartmented bottles.

Did I say what size marbles? I am sure one can find some marbles or beads that will be OK. As I have said, nothing to lose.

compu_85 · #9 11-10-2011, 08:52 PM

I've found that a good stinky carb cleaner is the only thing that will touch that gook. I've had excellent results with B-12 Chemtool brand.

-J

tangofox007 · #10 11-10-2011, 09:05 PM

Quote:

Originally Posted by ah-kay

Did I say what size marbles? I am sure one can find some marbles or beads that will be OK. As I have said, nothing to lose.

It's crystal clear that you have absolutely no idea how the current expansion tank is constructed internally.

compu_85 · #11 11-10-2011, 09:20 PM

Ya, the small chambers have only small access passages. You can spray a bunch of cleaner in there though and shake shake shake.

-J

ah-kay · #12 11-10-2011, 09:23 PM

Quote:

Originally Posted by tangofox007

It's crystal clear that you have absolutely no idea how the current expansion tank is constructed internally.

Do not understand what your 'current' means. The car is a 1985 model so it was designed in 198x era. Never cut open an expansion tank so may be there are only pin holes in there. I do not know.

You have better ideas than just putting some cleaning fluid in there and give a good shakes?

tangofox007 · #13 11-10-2011, 09:36 PM

Quote:

Originally Posted by ah-kay

Do not understand what your 'current' means. The car is a 1985 model so it was designed in 198x era.

Somewhere along the way, the expansion tank designers returned to the drawing board. The result of their efforts was a tank with a maze of internal compartments connected by very small openings.

Quote:

Originally Posted by WNC123

I pulled a very nice (practically new) MB reservoir out of a car in a junkyard.

WNC123 · #14 11-11-2011, 11:10 AM

thanks for the input. i was not sure about putting carb cleaner in it in case it would react with the plastic and/or the o-ring on the plug, but i may try it. i think i will try simple green first.

yes, the newer tank certainly has a lot of weird chambers and passages in it. i would fill it and then shake it and it would then appear to be half empty. i could also drain it, then turn it, and more water/cleaner would come out. seems like a pretty intricate design.
when turning/rotating the tank when shaking it, it is clear that there are numerous chambers and passages in it.

bigblockchev · #15 11-11-2011, 11:39 AM

I have used Brake cleaner on badly gummed up expansion tanks. However the tank is only about $22 or so new. If yours has had oil in it it will be weakened and may crack at an inopportune time. Replace it and you may avoid disaster, at least you will be able to see the level easily. Cheers Dan