Re: 20HP Chrysler spark
YEP! Like I said: check the easiest and most likely things first---points and condensers.
Those engines WERE produced with electric start versions, however, while the installation is physically relatively easy, it is not so simple. While the starter motor is external to the block, not mounted on top like the autoelectric versions of the 15 HP engines, you need a whole bunch of other parts. The positive aspect is that you get to leave on the top mounted pull starter for emergencies. AND -- there was a hood with trim that allowed the pull start handle to protrude (most likely yours) and one with the handle totally enclosed for appearance. So, you would have your choice.
The starter motor, solenoid, and engine terminal strip are mounted on a cast aluminum bracket that bolts to the block underneath the carb. If I remember correctly, you must remove the carb for clearance while mounting the bracket. The bracket is held on with two of the reed plate bolts and four or six others on the front half of the block--I do not know if these holes were tapped on non electric start engines. So: you may need to tap the bosses on the block 1/4-20 or the english BA system or metric equivalent and get a couple of bolts 1/4 inch longer for the manifold and reed plate. The front end gets rather cramped. There also is a strap that wraps around the starter to help keep it from cocking and torqueing when energised.
The motor itself is a smaller version of the Prestolite motors for the three and four cylinder engines with a standard bendix assembly. It should be easy to find.
Because of the number of parts and the crowded installation, it is BEST to try to find a junked engine and salvage the electric start from it.
Cost? who knows? Whatever the market will bear, I suppose. But you should be able to find a junker for 50 bucks or less USA dollars. What is the pound now? Two bucks USA?
However, you can also try The Chrysler Crew and put in a classified ad searching for one (free ad). You can try Franz at franzmarine.com and see if he has a used assembly--but again, that's going to cost dearly.
I have a complete starter assembly but I don't know yet if I want to part with it and anyway, the shipping alone would probably really hurt your wallet.
AND as a last thought, ALL the engines were set up to accept remote control and cables. You just need to change the rubber plugs in the front of the lower pan and disconnect the twist grip and front mounted shift lever. --too much drag.
EDIT-----
I couldn't resist--I had to run out and look at my 25. The bracket attaches to the block above and below the manifold/reed plate. --Two bolts above and two below.
