When I had my engine (serial #12354317) rebuilt recently, I had the rebuilder save the crankshaft hoping that it my be one of the EE variety. By the attached pics, it's obviously one of the straight side throws variety but no sign of EE stamps anywhere. The only markings on it are the Ford and Transue&Williams logos with "U" stamp. There has been some grinding here and there by the looks of the metal discoloring close to the bearing journals. The rod and main bearing journals measure out at 1.248, with at most .0005 out of round. EXCEPT the 3rd main which measures 1.39 (no out of round). The scoring on the journals is minimal and only can be felt by running your fingernail along them.
It passed the 'ring test' well, and I am wondering if it is worth having it magnafluxed and the journals cleaned up in the event my current T attracts a "mate" in the future. Also given the accumulated crud on the most all the engine parts and dustguards, with the exception of the pan inspection cover and the head, I am wondering if this is the original crankshaft or had been replaced?
Are you sure the third main is .152 bigger?
Don't know about the 1.39? Otherwise polish up all the journals and use.
You probably mean 1.239. Sure its worth saving. Mains are typically rebabbited and bored to match each journal. The rod journals are very good. If it isn't cracked, its a good one.
Correction: 1.239 on the third main journal. Thanks, John.
Get it cracked checked, a ring test is like kicking a tire to see if a car burns oil!
I wouldn't throw it out even if was broken in half. The rear main and flange makes a good small face plate and the rest makes good stock for dies and tooling. It even makes good forge/furnace stock. But I'm a scrounger.
Your engine is an early '26, made in september 1925. It's very likely the crank is original to the engine, it looks like what's in most engines made from the spring of '24 through 1926. EE cranks were made later on, found most often in '27 engines. Being a straight side throw crank it's better than most diamond throw, one design improvement compared to the earlier type is larger radii at the rod journals (1/8", was 1/16" on older cranks).
If you find it crack free after magnafluxing, be sure the crank grinder indexes on the flywheel flange when setting it up to grind the third main - the flywheel and trans must run straight and true in relation to the mains.
But if the third main is nice and smooth, perhaps it was ground some time in the past and the block was repoured? Maybe new babbitt can be custom fit to the crank, no point in grinding off more than necessary of an already undersized crank
Model T cranks aren't beefy enough to withstand metal fatigue forever.. most will crack eventually, but hopefully not in our lifetime ;)
Roger, thanks for the info. I replaced this crank with a SCAT counter-balanced variety. So, with this engine, I am not worried about metal fatigue affecting it in my life-time...or a couple others for that matter. I don't know if these early straight sided cranks have the same reputation for toughness compared to the EE variety. If it isn't as serviceable as the EE cranks, I would probably keep in my parts pile if someone else who can't afford a new one might need it.
Guys if you need to get a crank built up Homer Bracket use to do mine. I don't know if he is still around or the name of the company or where it use to be. South Carolina seems familiar to my mind. ??? I cannot remember things like I use to any more it seems. (?) But he submerged welded several of mine. Straightened them and you told him what to make it to (O.D.) after you had line bored (cleaned) good old original babbit still left in the block. I have had him make a few that were .003+ and .005+ years ago. So you COULD find an oversized shaft in one of your engines depending on who did it. Jess Bonar put me onto him in the mid 70's.
Joe in Mo.
joseph brings up a good point. the crank shop near me does nice work on t's and a's, and they also spray weld up bad cranks. not sure what it cost, but whats the viewpoint here as to if it makes a crank more brittle, or other bad effects from the weld
Thanks for all the feedback. Right now I probably need to spend a few bucks and get it magnafluxed for cracks, then make a decision if I want to have it cleaned up right away or store it for the future and do it when needed.
Looks like normal wear to me after almost 100 years.
I would recommend you magnaflux it and then straighten and grind it.
Not everyone can afford a new crank.