should you replace the spools that go under the magnets or can you reuse them? Do they compress somewhat so that the magnets are all at the same height when adjusting the height of the magnets?
I reuse mine. Some do compress, but you can get around that by how you position them. I've never seen the need but you could machine off the compressed end and use shims. You have to adjust the height of at least a few of the magnets anyway.
Beware of following Fords suggested method in the manual to adjust the height of the magnets with a hammer..
The magnets are brittle and the aluminum spools may also be less pliable/more brittle now than when new. Shimming/filing off material takes more time but we've got more time for our hobby than mechanics back in the day had for customer jobs. (The suggested time for the various repairs is another joke in the manual)
To amplify upon what Roger stated; it depends upon which type of spools you are referring to. I have reused the brass spools with absolutely no problems. Simple turn them a quarter turn so you have are using a previously unused portion of the magnet contact area.
In my experience the aluminum spools are highly prone to crushing and crumbling when setting the magnet height. For this reason I NEVER reuse the aluminum spools. It is cheap insurance to simply replace them.
Ron the Coilman
one shop i know of just puts them all together and then puts the whole thing in his flywheel surfacer and grinds them all the same, then shim the coil ring out
I have also seen that done, but I wouldn't want to do it before getting the magnet heights within a few thousandths difference. You can fine tune the magneto gap easily using that procedure.
Ron the Coilman
The flywheel surface grinder sounds like a good thing till you really think about it, magnets and metal shavings. Then also, the next person now has keepers of different thickness along with the spools to deal with.
I have put 3 engines together with original aluminum spools. I have shortened some with a hammer, but I removed them from the assembly to do it. I have had no problems with these spools. I wouldn't bash the magnets to correct the spool height. One engine I set up with the K.R. Wilson gage, and two without it. I turn the engine nose down and use a sling and a winch to take the transmission on and off. I set the mag coil true with a scale and feeler gages referenced from the crankshaft flange. I set the magnet height using a dial caliper. The retainer plates and magnet thickness aren't really very accurate so it takes some fiddling to get the gap within tolerance for any magnet at any coil pole.
One other thing, unless your drum bushings are in tatters,leave them alone. The gears will seek their own level and you will have a quiet transmission. Make sure the triple gears have plenty of clearance if you replace the pins and bushings.
I have a concern to my self I replaced the transmission bronze bushings and honed each bushing to a perfect fit, however here is the question. I honed the triple gear bushings by hand with a small hone with lots of solvent to float away the particles to a perfect fit, my concern is wheather the bushings are perfectly vertical. The hone seemed to track square but how do I tell? Are they that fussy? Should I remove my perfect honed bushings and take them to a machine shop and have them redone in a hone jig for perfect alignment?
David, your method isn't the best practice, but it has been working for many home mechanics. I remember Reid in Florida used the hone method on his coupe and it was working real fine until he was t-boned.. It's not a Swiss watch, it's an old trans that's more sensitive for too tight clearances than too loose, so if your clearances is on the loose side you'll likely be fine.