On a '93 104.942, was able to change out coolant pump without moving the PS pump. Delicate maneuver getting the old out and the new in, but do-able.

Green coolant is a curse. Had a green blob accumulated in the inlet. Stopped the radiator up. Flushed system with citric, refilled with G-05. PO relied on Jiffy Lube for maintenance.

I will also say that this series (104.9XX) is a bit under-cooled IMHO, judging by the size of the radiator. It is a delicate balance, and requires regular maintenance to keep the system operating consistently. UPDATE - The thermostat must be re-installed with the small hole/ball valve at the highest position in the recess housing. This prevents air-lock. Otherwise vacuum will be present via thermal expansion/contraction and the engine may overheat.

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327K on 1986 W201, 602.911, 722.414 2.5 190D ("The Red Baron")
139K on 1993 W124, 104.942, 722.433 2.8 300E ("Queen")

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Do not worry about your difficulties in Mathematics. I can assure you mine are still greater.
- Albert Einstein

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