Expert: Kevin Pilotte - 4/5/2006

Question
Hi,
I replaced the AMC 360 engine in my 81 jeep with a 401 engine out of what I believe was a 71 Jav.

The Harmonic Balancer on the 401 is a 3 bolt design. The Crank Pulley is a 2 groove pulley.
The 360 had a 4 bolt 3 groove pulley.

The AC and ALT on the Jeep are turned using parallel belts. These would basically be the center and inside grooves on a 3 groove pulley. The outside pulley runs the PS pump.

I was able to obtain an adapter that adds a third pully to the system (for the PS Pump) but my problem is the crank pulley grooves are a slightly different size.  This keeps me from running the parallel belts and a single belt slips.

1) Is there such a thing as a 2 groove 3 bolt crank pulley where the 2 grooves are the same size? If so, what might I find them on?


2) Was there ever a 3 groove 3 bolt Crank pulley made where the center and inside grooves are the same size?

3) WOuld it work if I drilled a 4 bolt Crank pulley to the 3 bolt pattern (Done professionally).

4) Taking a different approach: Can I exchange my 3 bolt HB for a 4 bolt HB if the 4 bolt is for a 401?  Some folks have told me that the assembly must keep the HB it was balanced with (btw this engine will almost never see anything over 4500 RPM)

Do you have any other thoughts or suggestions?

Thanks!  

Answer
This is a good one. I have not experienced this condition so give me some time to dig up an answer for you. I am putting it out to some other AMC afficiandos. Please send me your email address and I will answer you directly.
kepilotte@yahoo.com
Kevin