1985 merc 470 issues

[tradesman59]

I am a recent owner of a merc 470 in a 21' success boat. I have put about 20 hours on it so far this year. When I got the boat there was a blown coil. It was also the wrong coil. It should of had a resistored coil and did not. Since I just bought 2 new coils w/o resistors and did want the expense of replacing them again I simply bought a couple of ballast resistor for a 73 dodge 225 engine and put one is series with the running voltage supply of the coil. This worked well. However I seem to need to adjust points about every 3 hours of run time. The engine will backfire after awhile and boggs out of the hole. I like the engine in this boat and it is good on fuel. This boat is not a rocket but I had trouble pulling up a skiier last weekend. I think one of the lobes in the distributor may be worn. The boat only has 220 hours on it if the meter is correct. I know where thboat came from and I suspect it is.
I am thinking of going to electronic ignition and want to replace the complete distributor assembly. What is recommended for brand and where do I find one?

 

[Don S]

Re: 1985 merc 470 issues

Get the right coil and it won't burn up the points.

About the only thing you can do for a 470 is to go to the Pertronix conversion that replaces the points, in your distributor.
But fix your coil problem before converting to electronic. They are designed to use the same coil and wiring as the points system.