How do I fill a 300SDL (6 cyl) with coolant?
 

I Drained my '87 300SDL 6 Cly Diesel for a flush and new coolant and I can't seem to refil it. It only took about 1 1/2 gallons. I idled the enging until it was hot but no hot water went into the radiator. I loosened the top hose from radiator but only cold water came out.

Whats the secret? My older 300SDs always filled easily.

P E H

I've always had a problem with that, so I undo the top hose at the rad. and fill.

We have a tool that vacuums down the system and sucks in the water. This prevents air bubbles. If you don't have one, you should pull the hose from the radiator side and fill slowly until a large quantity of water comes from the radiator. Turn on the heat to full and start the car. Run at 2000 till you feel heat.

My mechanic (who worked at the dealership for 14 years) told me when they had a difficult-to-purge car, they would drive it to a nearby hill and park it with the front end pointing uphill. He would just fill it via the pressure tank as usual, but add coolant SLOWLY which allows the air to purge itself.