85 300SD ? hose @ Rr of head above IP ?
 

Just curious when I was replacing my GP's last month it was a pain working around the large black hose on the last plug @ rear of the head. It is above the rear end of the IP and snakes through the firewall and then heads to the battery area. In the future is it okay to disconnect it for better access ? just for that GP ?
Also after the new plugs the car starts great even in the cold. Last night just for chuckles since it was getting down to 23 degrees here I plugged in the block heater for about 1.5 hours before starting it. Wow started on first crank
no delay no issue with wanting to stall.

That hose supplies coolant to the heater core and windshield heater. If you disconnect it, you will lose a little coolant. Because it is a special hose with a smaller hose grafted into the side of it, it is expensive to replace if you damage it while removing it.

FYI
 

Heater Hose
MB# 126 832 28 94

Fastlane: Heater Hose
http://catalog.peachparts.com/item.wws?sku=W0133-1621684







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