Broken Crankshaft?? WTH :/

[Ricky Gee]

Update;
I was able to get the engine tore down and didn’t see any reason for the crank to just break. Looking at the crank it looks like a bad casting and it finely gave way. Ive got 2 other engines, one of them seems to be free and only has 34K on it. It has been sitting for awhile and its condition is unknown. It does spin free though, so hopefully i have a runner. It’s an earlier model, looks to be a 78 0r 79 which seems to be the better years. Looks like they did some changes in 1980 that slightly detuned it? Crossing my fingers that i have a good one. It will get a good look over before i install it.
i do have a question, I couldn’t get the alternator rotor off the crank and the broke crank wont come out of the case till it’s removed. What’s the secret? I have a puller but it wouldn’t budge.
Thanks for the inputs..

[bikerphil]

A 16mmX1.5 bolt threaded into the rotor and using an impact gun, the rotor will fall right off.

[Ricky Gee]

Bikerphil

i am a little slow this morning and I'm not following you here. I don't remember seeing a place to thread a bolt into the rotor other than the center bolt that holds the rotor in place. Can you help clear the cobwebs out of me?? LOL

[bikerphil]

Look at again, there are threads in the rotor and the bolt pushes against the crank popping the rotor off.

[DEEBS11]

[DEEBS11]

Many of these to choose from on the internet.

[Ricky Gee]

This make sense. I was thinking the bolt that held the rotor used those thread. Now to find the bolt required. thanks guys.

[DiverRay]

The bolt to remove it is 16mm X 1.5mm X 45mm. I'm buying a new one to use from Tacoma Screw, and they have a 50mm that has threads all the way up. 1.25" is all you should need for bolt length, 50mm is about 1.75". Yeah, not exact, but close enough for government work....

[Ricky Gee]

thanks all.. still looking locally for the correct bolt. i may have to order it if i cant find one.

[DiverRay]

Google search for metric bolts near you. Tacoma Screw is a large company, and has offices in most metro areas. Granger may also carry a bolt that will work.

[bikerphil]

A few pics of the rotor pulling process...