Does anyone know a way to make this radiator cap round again to make it usable? The threads are good, but the whole thing is kind of bumpy instead of round, and it will not thread into the radiator neck:
I want to use it as a spare and also to keep anyone from walking off with my nice one...
Round wood peg in a vise and a leather mallet ought to do the trick.
And if you have a wood lathe, make the peg fit both the ID and the dome on the top. Actually, you'd have a rather awesome tool if you did that!
Oh yeah - this is IMPORTANT - before you attempt to straighten (or actually re-rounden!) the cap, you need to anneal it, otherwise you risk cracking it, ruining the cap. Brass anneals at between 480 and 650 degrees farenheit. No hotter - you don't want to sag the cap. Get it hot for a few minutes (IIRC it will be dark maroon in a dark room or oven or somesuch when it's done) and let it cool.
Or go to a bearing house and see if they have a single large ball bearing that is just the right size; then gently force the bearing inside the cap and tighten a screw type radiator hose clamp around the outside until it is round.
Thanks for the ideas. I'll see if I can make something work.
Well, success! I ended up using a water inlet that goes on the side of the engine block as an anvil and lightly tapped all around the threads of the cap with my lead hammer*:
Then once it started a few threads, I used valve grinding compound to work it into the neck deeper and deeper until it goes in just fine (a few issues with the old, after-market non-Ford radiator for my stationary engine, but that's another day):
The lead hammer is actually babbitt from my engine rebuild. The guys asked if I wanted them to keep the old babbitt and make a soft hammer for me, and so they did. Very handy:
Thanks for all the suggestions and ideas.
Who made the babbitt hammer? looks similar to the hammers the guys make here in escondido.
Vic & Dale's engine rebuilding did that for me. I use it a lot...
yep those are the guys!