I suspect the previous owner took a short cut and replaced the flexible part of the oil line with rubber hoses. The rubber hose bursted. You can do the same with good quality hydraulic hoses. Or bite the bullet and replace all 2 with OEM. Replace with OEM is a lot of work. How long you want to keep the car? Good luck.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.