90 350sdl...want to replace my mono valve.
The heater hose to the heater core goes into the 1st firewall and there is a computer looking thingie in the way between the 1st and 2nd firewall.

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82 300D....went to MB heaven
90 350 SDL....excercising con rods

You want to replace the monovalve cartridge or the entire monovalve? If it's just the cartridge then you only need to get to the 4 screws atop the monovalve.

The computer thing is probably the ABS controller. There's one or two screws or clips then it lifts out.

Sixto
93 300SD 3.0

There's a large section in the middle of the false firewall that's removeable.

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1984 300SD Turbo Diesel 150,000 miles

OBK member #23

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