Installing Crane XR 700 Electronic Ignition on the Monk's Chrysler Crown M7
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Above and below - the old Autolite distributor has worked well for years, but the bushings and cam lobes that open the points are worn and the dwell is iffy and jumps around quite a bit at idle. Time for electronic ignition.
 
I removed the distributor and mark the angle of the drive shaft for re-installation reference. Points and condenser coming out, never to return (I hope!)
Above - distributor on the bench in the shop, it's showing 60 years of grease and grime, time for a good clean-up.
I disassemble the breaker plate and centrifugal advance mechanism. I won't need that big suppressor coil any longer, no points means no static.
The flyweights in the advance mechanism are dirty, rusty, gummed up and worn.
The interior of the distributor is very gummy from years of grease caking the innards. That's a grease cup screwed into the side of the distributor housing (below).
 
Above - the breaker plate after clean-up with the new electronic LED signal unit in place for a trial fit.
Above - I cleaned the housing and wire holders and painted them Chrysler Crown Blue. Below - the distributor shaft gets cleaned thoroughly and the advance mechanism gets cleaned up, filed smooth a bit and lubricated prior to reassembly.
 
Above - here's the whole shooting match from left to right: resistor block for the coil, new Crane 40,000 volt coil, Crane XR 700 electronic control unit, old Autolite distributor all cleaned and painted and center stage the breaker plate with the LED trigger and target wheel next to it.
Above - I had to trim the points post down a bit to clear the target wheel. Below - the breaker plate installed, target wheel and wires secured.
 
Close-up of the assembly.
Above - I set the clearance for the target in the LED trigger assembly.
I grind a hole in the side of the distributor so I can set the optical timing. Below - you can see the tip of the rotor. The techniques is to set the trigger block so that the LED light on the control unit comes on just as the rotor is lined up with the plug wire terminal as shown in the photo below.
Below - new wires. 8mm silicone units to handle the 40k volt coil.
Below - I connect the control unit and distributor to 12 VDC using the trucks battery so I can set the optical timing. You can see the red LED on the control unit that comes on when the rotor is lined up with the plug electrode.
 
Above - I go down to the boat and install everything. Fires right up and runs great. It's a significant improvement at idle. Below - the blue silicone wires give a strange, washed out appearance with the flash. Looks Photo-shopped.
I can't time it yet, so I set the timing by putting the distributor back in exactly where it was before. The engine manual procedure for setting the timing is to take the boat out, warm it up, run under wide open throttle and advance the distributor until the engine starts to ping, then back it off. That's a unique method, indeed! But that's what it says. In fact there are no timing marks on the flywheel I can find and no hole or mark on the flywheel housing, so that must be the real deal.
Next step - I have to install a new distributor cap and then Renee drives the boat while I set the timing underway - should be sporty!