3.0 Crank shaft Spline question

[Mike Nass]

I've got three 3.0 cranks i picked up in buy out...   2 of them have fine splines and one is a course spline...    whats the application for each?   Educate me boys....   

[Chaz]

Coarse spline was 1995 and all of those had a two-row bearing on the center mains.
If your two fine spline cranks have single row center mains then they are good cranks. If they also have two rollers per row, they are 1996 to maybe 97 or 98 and are nothing you want to use in a build.

[Dave S]

So Chazz.....are the cranks bad or the rollers are more prone to fail because of short length?....

[Mike Nass]

Thanks for the info Chaz!

[Chaz]

The rollers are just about as long as they are in diameter. So they aren't very stable. I had a motor with an early crank in it that would "shut itself off" abruptly. But fire right back up and run till it would randomly do it again. Passed all fuel and spark test's , so I said , the only one way to find it , is to pull it apart and see what we got. There was a chunk taken out of the crank surface , all the pins had heat marks and a few with rounded/chipped corners from where they dropped in the hole and locked it up like a park pawl in an automatic transmission. Put a late model crank in it, cleaned up the bores and clipped the heads. From last I heard, it's still running strong ..

[Capt.Insane-o]

Welp... on the styrofoam motors I like the double row center mains. I have a lot to offer on these pieces of ****, but that is for another time.

[Dave S]

cappyi....ya..... dobbt botem.....closer to yje main rying masss the better.....

[Chaz]

Out of the 24 years of production there was :
1 year of coarse spline.

23 years of fine spline.

2 or 3 years of two-row bearings.
21 years of single-row bearings.

I have found some good use's for the twin-row cranks :
Doorstop.
Take up space in my scrap steel bin.
A source for a used top and bottom bearing.
Top snout makes a good flywheel lightning mandrel.
Bottom flange to the bottom center main makes a good dead center tool for shortening mid-sections.

Other than that, I'll do like the factory. Use the late model cranks ... and never look back ..

[Dave S]

Chazz.... ya found 5 good uses.... for a usesless crank....