No circulation in cooling system ( 78 240d )
 

So far I've replaced the waterpump (old one looked fine), checked the belt, topped off coolant, checked thermostat(even tried running with it removed) and I'm still not getting any circulation. Radatior is new and cold to the touch, hoses are all cold and the temp gauge shows it overheating everytime(verified with laser thermostat).

The car didn't start overheating until i added some coolant to the system. It was running fine up until that point. From then on it would overheat, if I drove it long enough it would appear that the coolant would circulate intermitantly I'd be driving with the guage way above 175 then all of a sudden it would drop to 175. Unsure what else I can try before throwing more money at the problem. I know it could be the head gasket, anyone know of anything else I could try?

Check for an internally collapsed hose by chance?
I've seen that on several occasions.

Air lock? Are you getting heat from the heater core? Have you tried burping it? Have you tried adding coolant via the top radiator hose directly into the block?

Doesn't appear to be a collapsed hose, but will double check.

Haven't checked for heat from heater core yet. How would I go about burping it? I haven't tried adding coolant directly to the block yet either. I will try after work and report back.

Point the front of the car uphill--put on ramps if necessary. Run the engine with the heater on full blast until the air lock burps out.

I have ramps, but no hills around me. Doesn't need to be so steep?

Needs to be steep enough to get the air to move to the radiator.

Airlock in the heater core isn't going to stop flow out of engine and through the radiator.

Wonder if theres a wad of scale or sludge blocking the upper / lower outlets?

Reverse flush ?

The point of operating the heater is not to remove air from the heater core. It is to vent air from the head so that coolant can reach the thermostat.

No bypass on the pump then?

Ok.
Learned something.
If he can't elevate it, adapt a garden hose and run it through the core?

My old Midget had a valve on the side of the head but it didn't need to be open to clear the head.

I took the cap off let the car get to operating temp at an incline then filled with coolant to the top. Turned off the car and put the cap on. I attempted to burp it, maybe i'm doing something wrong, but nothing happened. Heat and fan set to max and remain cold while engine temp approaches and exceeds 200.

What color is your coolant? I ask this because you could have a blocked coolant passage in the head somewhere due to rust or other contaminants.

Putting coolant in the radiator doesn't fill up the block, that's why I said you should the block using the upper radiator hose.

It's green, don't see anything wrong with it.