I've been looking for either this one or Haunted House for quite a while. I found this one fully working at an auction.

It's a fully working machine, so I'm fortunate. All I have to do is to go through the machine to learn about it and fix any minor glitches. I also should tackle the grounding issue since this machine never had the grounding modifications done to it.

The only thing that didn't work when I bought it was the spinner motor in the backglass. There are well documented fixes for the motor so I studied them. I bought the recommended motor from Grainger but I wasn't crazy about the methods used to install it. All the methods I found crammed the motor right against the backboard and circuit boards, squeezing wiring harnesses and connectors out of the way, and placing the motor casing right on the bare wires for the lights. Plus you have to make spacers to move the plastic spinning disc out from the backboard. Nobody seems to have a problem with this method, but I thought it was taking a lot of chances when not necessary.

I thought there must be a different way. I don't think this is an easier way, just a safer way. It is about the same amount of work.

I found that there is an extra 3 inches of room behind the new motor to allow it to be moved away from the backboard and circuit boards when the backboard is in the closed position. I determined that you only need to move the motor about 1 1/4" + away to clear everything. Then you aren't cramming anything in and you are away from all existing objects.

You need to buy a 5/16" shaft coupling and metal rod for the pin extension. This brings the shaft out to the original location so you just slip on the disc hub and fasten the disc.

I also didn't want to drill the backboard at all. No modifications. I found that I could use the existing motor mount strap that attaches to the front of the backboard. I removed the old motor housing so I only had the flat strap.

The benefit of all this is that now I don't have to work around the pinball machine at all until I install the motor for the final time. All the measuring/cutting/centering/swearing and injuries of the motor mounting is done on a workbench. I haven't disconnected anything, moved anything or drilled anything on the pinball. When I throw things out of frustration nothing will hit the pinball machine, I'm nowhere near it! Blood will not be shed on the pinball but in my workshop where it belongs! That is why it is a safer way!

PARTS:

The existing motor mount strap with my adapter attached.

This is the spacer (on left)

I glued together 1 3/4" dia. discs of wood to a total height of 1 3/4". I think 2" might be better but I used 1 3/4". Drill a 3/4" hole through this and cut in half. One half is all you use as a spacer.

The motor has an alum. angle attached to the threaded studs. It has two holes that attach it to the wood spacer. The shaft coupling and an extension rod are attached to the motor shaft.

The other end of the wood spacer has two holes to attach it to the front mount strap.

You do the visual centering of this assembly while on the workbench. The hole through the original front mount strap is the center of the spinning disc on the machine. Just center it by eye and transfer the hole locations with some oversize to allow tweaking.

To mount on machine you take off the front metal strap and attach it to the front backboard in the original location. Insert motor/spacer/shaft assembly from behind, line up the holes in the front strap and attach with screws, tweak for centering.

Now hook it up to the power connection and BOB'S YOUR UNCLE!

The disc rotates CCW (switch motor leads if not). I found that this motor rotates at 1.5 rpm when hooked up to the original motor connector (6 volt).

Usually after I finish a project using what materials I have on hand I figure out a better way to do the same thing.

If you are good at visualizing things and don't mind drilling at least three holes through the backboard try this alternate method for a sturdier mount while still spacing the motor away from the backboard:

You can skip the front mount strap and wood spacer by just using threaded aluminum standoffs threaded on the motor studs and mounting directly onto the backboard. These standoffs are in hardware stores in the nut and bolt aisle (a good hardware store, not Lowes or HD!). Find the right thread size standoff (you will have to assemble a few short ones together with setscrews to get the length). Hold the motor and standoffs up to the backboard and move it around until the standoffs are in a safe, open area for drilling and the motor shaft is centered. Mark the hole locations and drill the backboard.

You still have the use the shaft coupling and the shaft extension rod.