Coolant Flush old school?
 

Searches on this subject are very futile... either TMI, or not enough...
'94 W124 M103, can I just cut the drivers side rear heater hose and place a bronze T (instead of the dreaded Prestone plastic one in the kit) and attach a water hose and flush my cooling system like we did "back in the day"?

Would I still need to put in a special 'open' thermostat? Or could I do it without. Or just remove it temporarily while flushing?

Plan would be install T, remove engine block plug and run water hose at low pressure until clear...

MB way is to attach special radiator hose sized T at top of radiator with water hose and install special thermostat.

Just trying to keep this simple. I don't need lectures on what antifreeze to use or 'make sure you run heater' etc, I know all that. Just want to know if the old school way would damage something, and the engine block plug is not something I'm used to from my shade tree days working on US cars.

you can't have a 103 with a 94.....i would remove the thermostat and put in the t..... you will be fine....

Has the coolant started to turn more towards yellow / brown rather than green? If the coolant looks greenish I'd do a 1X fill with water then drive for a few miles rinse. Heat does wonders in cleaning things out.

If the coolant is brown, opening the block drain then filling from the tank would be the first step.

A word of caution, if your drain is like mine, it works like a brake bleeder screw. Mine has a thread issue that prohibits opening past 3/4 of a turn. If it is forced past that point I'm concerned that the threads will be torn out.

Just pulling the thermostat on these cars isn't a good idea. The disc on the bottom of the stat is needed to block the bypass when the stat opens.

Thanks. Even MO Simpler... :) and ches... meant 104 car. Almost 50 and feeling forgetful...

remove the T stat and plug the bypass hole with a shorty rubber cork, install cover back without Tstat, you would then essentially have a forced open thermostat.

Go to town with flushing.