103 engine 300E bleeding cooling system? - PeachParts Mercedes-Benz Forum

lsmalley · #6 06-19-2018, 12:45 PM

Quote:

Originally Posted by murphysf

Hello

My 1987 300E does not have a bleed screw in the top of the thermostat housing. To bleed the cooling system there is a bolt on the top of the head.

I understand that the housing was updated with threaded hole and bolt / crush washer..

I am not sure which point is higher, the bolt in the head or the screw in top of the thermostat housing?

Why and when was the screw added to the thermostat housing?

I will soon be replacing my thermostat and was wondering if I should change the housing to the updated part while I am at it?

Bleed from the coolant reservoir. What I have found that works amazing is to add the coolant and jumper the aux water pump. Keep adding the coolant and the aux pump will do the work in getting it circulated and pushing any air out of the system.