John Deere 70 / 730

will a John Deere 70 flywheel fit on a 730 and function correctly

No

can you tell me if a 730 flywheel has slight indication of a crack if a taper loc can installed on it

Gas or diesel ? I'm pretty sure all the diesels will interchange, but on a late 720 and 730 IIRC something is different about the pin to drive the slinger as you don't need one. Or is it the other way around and you do need it and the early tractors don't ? Parts book will tell you.

If you have a crack now you sure do not want to install a taper lock into that one. I prefer the fylwheel made just for taper locks as it is stronger.

Quote: matt1890
will a John Deere 70 flywheel fit on a 730 and function correctly?

YES is my answer BUT read my answer.

In 1976 my Father had to replace the Fly Wheel on his Diesel JD 730,and only a JD 70 Diesel Flywheel was available:

I weighed the JD 70 FLYWHEEL, counted the number of TEETH on RING GEAR, checked all timing marks, checked were the master spline and the "V" marks are.

The only ONE difference in the FLWHEELS was, the JD 70 FLYWHEEL had to have a RING / SPACER machined to be placed between the Inboard side of the JD 70 FLYWHEEL so as FLYWHEEL would not CONTACT the CRANKCASE of the JD 730.

Place a straight edge on the inboard side of the JD 730 FLYWHEEL, and check the distance from the straight edge to the HUB of the JD 730 FLY WHEEL. Do the same with the JD 70 FLY SWHEEL and you shall see the thickness of the spacer ring required to position the JD 70 FLYWHEEL correctly on the JD 730.

I drilled a HOLE in the spacer ring so as the SLINGER RING can still be driven by the DOWEL from the FLYWHEEL. We installed GRADE 8 BOLTS, torqued to JD 730 specs. Tractor ran approximately 1000 HRS with JD 70 Flywheel and was still running properly when Tractor was sold.

The JD 730 had a Starting motor (NOT straight electric)


Bob....Retired Power Engine.......

If the old flywheel was loose on the crank splines. There is no used flywheel that while stay tight on the worn crank splines.
Time for a taperloc flywheel if the crank splines are worn.