just got to taking the heads off the flathead I got a while back to inspect things and I am really happy with what I see. Cyliner walls look brand new, as do the pistons. Valves are older but seem to be really clean, and in great shape. Besides the dozen or so dead flies on top of one of the pistons (Im guessing that exhaust valve was maybe open and they decided that was a good place to die) My only concern is the water jackets...common area of concern on a flathead I figure. Is there a process to clean these at home without taking apart the entire motor for an acid bath? That brings me to my next question...if I take it in for a bath, it must be totally dissassembled, correct? Thanks for the info.
Based on what I see, the only thing I would do is pull the water pumps and look inside. If there is not a lot of scale, put a new gasket behind each one and bolt them up. If I felt really concerned, I would run that radiator flush from the parts store before putting in antifreeze. For mine that I got with a car around it, I pulled the thermostats, did a motor coolant flush, put new thermostats in it and then antifreeze. The green stuff is still green and no issues.
The old school method of cleaning out flattie blocks is to roll it around and bounce it on a wood floor. Don't get crazy and bust anything! Just keep at it, you'll be amazed at the amount of scale that comes out.
Hi, What I would suggest is to make conical strainers and insert them inline on the upper hoses. That will catch excess trash, before it clogs your radiator. I also make aluminum radiators( since I switched from the brass one, I haven't had a clogged radiator since). Best Wishes ,Flathead 26 ( youtube)
One suggestion that I thought was cool was to take an old speedometer inside cable, fray one end and put the other end in an electric drill, fish the cable inside the water jacket holes and spin the shit out of it with the drill. It will scratch the scale off of the water jacket and then it can then be flushed out. Remember when Dupont? sold block flush that was an acid and the neutralizer was included to stop the cleaning action and then fill and flush. The new stuff is not as effective IMHO. Probably outlawed by the EPA.
From the perfect cylinder walls and the writing on the piston tops,,and the new looking gaskets,,,wouldn't that suggest that it was recently rebuilt just before you bought it? Looks like it just needs to be ran. Just my opinion. Tommy
I wouldnt say rebuilt, but freahened up. New rings etc. The water pasdages in the heads are fairly gunked up. Removed water pumps and there isbsome loose scale in there...actually went in there last night with a wire, and knocked off a stelagtite of sorts...about a quarter inch long!