I have a 55 235 that is still in the pickup, but I have the whole front end off so it is easy to work on. I have a brand new radiator, not yet installed, so I want to get this junk out before I put it in.
I soaked the whole engine in vinegar for about a week. Then pulled the thermostat out and connected the water pump directly to the water discharge. Ran the engine until it got hot. Left it sit for another week. Then flushed it out. Got out enuf rust to make my own movie.
Removed the drain plug at the back and no joy whatsoever. Black tar like gunk. Poked and prodded, no joy. Hooked up water hose direct. No joy. Pressure washer as best I could. No joy. Left it open.
When I try to push something in there, there seems to be something hard fairly close to the opening. The gunk is somewhat hard, and it is hard to tell if it is gunk or metal. I think it is metal. So I don't want to get too aggressive. I don't know what the architecture is inside of that hole, which direction the channel is (gotta be up) and how aggressive I can be. Don't wanna bugger the threads. Think I'll leave a small 1/4 nipple in there to protect them while I'm fishing.
Pulled the water pump and used a long stick of #6 copper wire, water hose, pressure washer, elbow grease, and a liberal sprinkling of choice words. My roughneck and I repeated that for about 2 days on and off. Water at first looked like a rust milk shake. Now it runs clear, even after I prod a lot with the copper stiffie. The cylinder steel walls look like new. Still no joy with the rear drain plug. Not a drop out of there.
So I put the water pump back on to close the hole, and mixed up a cocktail of 1qt degreaser and 1qt Lime Away. That got hot and boiled up pretty good. Poured it in and it has been sitting there for a couple days. Still no joy on the rear drain.
I think I may try the speedo wire/sleeve trick with a drill. Have drill, no speedo. Maybe some cable and a piece of copper tubing.
Once I get a little hole opened up, I'm concerned that that all I will end up with is a small hole and still a lot of gunk. Considering going a little more radical with muriatic acid. I think once I get done with the acid, assuming it works, I need to run some baking soda thru the system to neutralize the acid left on the metal walls. But I have to find joy first.
This is a lota work for water constipation. Any suggestions for this working in the dark?
