I'm letting the boy work on this as it's his car and he should be able to turn a wrench.

The car overheated and he didn't know why. So we figured it was an obstructed oil cooler, or flaps may have been closed. After poking around and checking he found the fan has come loose. From what I can see with a mirror the center bolt has backed out and is MIA. Along with missing center washer.

What should I be looking at here?

This happened to me on a road trip in my old black car. There is a woodruff key on the crankshaft also that prevents the fan from spinning. On mine that had sheared off, and it also scored the keyway on the crank that it fit into pretty badly. I ended up having to drop the engine and pull the fan housing off to properly analyze and repair the damage. If the key didn't shear it might be as simple as replacing the key and re-assembling. If the key did shear it probably damaged the keyway in the crank, and to properly repair it you'll have to replace the crank. I ended up sanding the scored bits flat, inserting a new key, and re-assembling with JB Weld. It got me home. When you bolt it back together, make sure it bolts on flat into the taper, if there is wobble on the fan it won't hold together long.

-Ross

In general, replacement can be really simple or major-league difficult. The big issue is whether or not the crank and/or fan hub are damaged. There are 5 main components involved. The crankshaft, the hub, the Woodruff key, the special washer, and the bolt. All need to be correct and in good condition. To find out whether or not the components are OK, you'll need to get in there with good light and a mirror. Check the condition of the snout on the crank, and especially the condition of the keyway. If the snout is smooth and the taper undamaged, and the keyway is clean and the edges sharp, you've gotten past the difficult (and expensive) part. Examine the tapered surface on the inside of the hub. If it's good, then you clean everything up, replace the seal and the o-ring on the crank, and install the key, the hub, the correct thick washer, and the special locking bolt. Install the spacer and the fan using three bolts of the proper length, hardness, and configuration. Some fans use hex head bolts, some use Allen head bolts. The torque is 15-18 ft/lbs. The taper takes the load, not the bolt.

Note! If there are ANY damaged mating surfaces, you'll need to replace the affected components! A taper fit by design MUST be clean, smooth, and tight! I probably have a hub somewhere, and I KNOW Bruce Stone has some, 'cause he got at least one from me.

Good luck, The Cap'n

I just looked at those pictures. It NEVER would have occurred to me to shortcut that repair! Luck alone is holding that one together ................

The Cap'n

It certainly isn't a proper repair, but it got me the 1200 miles home.

As usual, the Cap'n is spot on. The fact that it overheated suggest that the fan was not turning, so the woodruff key might be missing as well. I have a few hubs with bolt, washer, and key if you can't find them locally.

I would have thought that an alternator light would have gone on too after a short while. Question for the Capn or anyone else. Can this part of the crank be repaired through a welding process? I am thinking either directly welding or metal spray. Then repair the taper shape? Or is it just not worth the trouble?

I don't see why it could not be welded, but it would still have to come out of the case. I think the taper will have to be perfect or the fan will not run true.

Any chance of lapping with an old hub? Assuming the damage is minor.
No, I don't think anyone is going to be doing a quality metal repair between the firewall and the engine upside down.

I'll post pictures later this evening (I'm shipipng now). It's amazing. the keyway is still good and the crank slot is still true. I'll put it togetehr and check, but Taylor may Have go Lucky!

Amazing this was simply able to bolt back together with a new Key.

LOCTITE EVERYTHING !