I've been trying to revive my 1978 Canadian Mini 1000 that had been sitting in a garage for 12 years. I finally got it started and idling, but the radiator started overflowing after running for 15 minutes, even though the temp gauge is below 230. (by the way, the car is running a little lean, which could be causing things to heat up).
The water has a lot of rust in it, so I decide I should flush the system and add some rust treatment. Ran into a bunch of issues:
I couldn't get the lower radiator hose off. I guess I'll try to reach it from the bottom and force it off the radiator. But, if it's so hard getting it off, I worry that it'll be hard getting it back on too. Ant tips here? Should I just try to remove the whole radiator?
Next I tried to take off the thermostat housing, and that was a pain, because the housing has a bracket that the smog/air pump connects to. So I had to take that apart first because I had to twist the housing to try to get it off. And I couldn't take the bracket bolt without taking off the cylinder 1 spark plug :/ Furthermore, one hole of the housing has a stud with a nut on top, and it wouldn't come off. The housing twists around that stud but wouldn't come off! I tried a lot of WD40 but nothing...what can I do? I don't have access to welding equipment or a blowtorch. I was thinking of using a metal file to make a groove in the stud so I can maybe use a large screwdriver and unscrew it.
There is no thermostat in the housing, there was no gasket...I think the PO removed the thermostat and did a poor job of putting it back together. I've ordered both parts but I can't put them in because I can't get the housing off!
I put things back together, and thought maybe I can improvise and just let water flow out of the thermostat housing to flush the system. I left the hose from the housing the radiator off thinking that that's where the water would circulate and enter back into the radiator. However, no water came out when the car was running. I checked and there's water in the rad. Also, a heater hose was leaking ( which I replaced) under the dash when the car was running, so I know that water is circulating up to that point at least. Am I thinking of this wrong? Water is supposed to flow out of the thermostat housing, right? Or maybe is the system really clogged up with rust that coolant isn't circulating? Could the water pump be bad? Any help here would be really appreciated!
Also, notice how the radiator is a different design from regular Mini rads, because of the smog/air pump. I couldn't find these for sale online...so just replacing this would be hard.
Here's the housing:
Closeup of the bracket: