So I bought a new/rebuilt D15B2 a year or two ago for my car. In the past few weeks I've been swapping it in along with an MPFI swap and wire tuck.

So today I go to put the crank pulley on as well as the belts in anticipation of FINALLY finishing, and my stock crank pulley is slightly too big. The diameter of the pulley is about 1-2 mm larger than the diameter of the shaft (i.e., the pulley is "loose" on the crank) and the crank pulley bolt is too large as well and won't thread in.

What gives?

 

The new d15 must be an 88' motor. They have a smaller crank snout than 89 and later.