Gurus: are these parts interchangeable?

[bradmeehan]

I'm swapping over some parts from an 85 Spree onto an 86 crankcase. The 85 flywheel did not fit onto the 86 crank so I used my spare 86 flywheel. I kept my 85 stator and pusle gen. Are those interchangeable?

Also, the bendix appears to stick out further in the 86 case.

[az_slynch]

Seconded. My '85 rotor doesn't fit on my '87 shortblock's crank.

Tempted to tear both motors down to directly compare the cranks.

[bradthreee]

After a look at the babbitts site the 86/87 alternator set is different than the 84/85. So, 84 and 85's are the same and 86 and 87's are the same. There are also different part numbers for corresponding stators and pulsers.

[bradmeehan]

Mine 'looked' identical to my spare from my 86 so I used it. It looks completely different than the 85 stator shown in the manual. But...it works. Maybe the PO swapped in an 86 before? Dunno

I did the full crankcase swap and the only things that didn't fit were:

Flywheel - shaft is too wide on the 86
Fan - holes wouldn't align
Fan cover - not deep enough to reach holes but has same part numbers
Bendix - who knows. Worked before I did the swap an hour earlier

[az_slynch]

Noticed something else when installing dem0nk1d's old '87 engine into the FailSpree. The pulser (trigger) coil for the '87 has only one wire (signal) while FailSpree's original coil had two wires (signal and ground). I'm wondering if I need to use FailSpree's pulser or if things will work fine as-is?

[Spreetard]

in 1986, the humble nq50 engine got revamped from the block up.
the swingarm on 84/85 engines has only four ribs of internal reinforcement, as with the two pictured below that i jacked from trafficjamz



both of the above engines are '85 blocks.
the 86/87 had more of a latticework, as is mostly visible in this OTHER picture i jacked from trafficjams, as i'm posting from his computer.

this is a 86 (with a cut down 84 cover)
the flywheels, fan, alternator, front pully, piston, exhaust port, reed block/reeds, piston,
exhaust pipe, and at least 1 other thing i don't know about were altered slightly over the four year run of the spree, and most of the changes were to the 86.

*edit; i know alot of the parts do interchange, but not which all ones do not other than the whole flywheel/fan combo. *