DIY Radiator reconditioning
I had a Cordoba that started to overheat but I was out of town every week ( truck driver ) during the weekdays. One Sat. I pulled the rad. and looked in and spotted some tubes stopped up. I was going to take it and drop it off in front of the radiator shop with a note but decided to try something. The worst thing that could happen was to cost me more money.
I rigged a holding bracket to keep the radiator upside-down about 1" off the concrete ( did this on the porch for comfort ). Placed a garden hose in the bottom hose (now on the top ) and started the water. I then used a rubber mallet to tap on the radiator every where I could without damaging it. I was shocked at the crap that came out on the floor. Put it back in and tried it. Problem solved.
One other thing I did that probably didn't help was I mixed baking soda in water and poured it in and kept the water flowing for at least 10 min. That was an effort to neutralize any acid that might have built up in the system.