Took the advice of Gregory Long and reverse flushed my cooling system today. Kind of a McGuyver kind of job. The residual water was not as “tar-y“ as I expected, but there was significant rust/crud left in the barrel. Hoping this helps cure bubbling/overflow issues. Have already made sure bottom radiator hose was totally sealed and closed down on the water pump packing nut which helped a bit (before I took apart to reverse flush). Boy, does the water pump move some water 😃.
Looks like about the most thorough flush it is possible to do!
Kirby: thanks for posting a photo of your reverse-flush setup. None of the photos I’ve taken over the years of this setup look as clear and self-explanatory as your photo does.
The beauty of this setup is that the water is heated by the engine, and HOT water is needed to soften, free up and flush out the residual old water pump grease that migrated from the pump to the radiator core, and clogged some of the tubes. Some low-suds dishwasher detergent added into the flushing water also helps clean out the residual grease.
Kirby: when you reassembled the cooling system, did you add a ‘footy-sock’ in the upper neck of the radiator to filter and catch any additional rust flakes that show up?
Hi Greg, thanks for your comment. I did not add the footie, I did know about that but chose not to, as I knew the car would be going down soon for a restoration. I did run evaporust which did more clean up. Cooling improved dramatically after I did this. When I did take the car down for the restoration, and removed the water jacket, I saw what others had indicated I would see……lots of particulate scale. After that will certainly use the footie when I reassemble.