Re: Tune-up
so how is changing the cap and rotor?? easy, intermediate, hard? im sure it would be easy once you have all the wires off but im just not sure as i have never done it. is it simple as pupping off the old one and putting on the new one. or do i have do take out the distributor>?
it would be for the mercruiser thunderbolt ign.
This fall, I changed the plug wires, cap, rotor and ignition sensor on a Thunderbolt IV equipped 1984 228R Mercruiser. I would rate it as easy. There is no need to remove the distributor, which I would rate as very hard. Those ratings are from the perspective of a non-mechanic owner with basic skills and tools.
But pay attention to the sensor wiring, if you change that. My sensor was the old style and the replacement was the new style. The Mercruiser documentation describes how to make the interface between new and old, but the documentation showed only ONE white wire with green stripe when there are TWO white wires with green stripe that go to the sensor. It would have been easy to miss that detail because on my installation (1984 Sea Ray SRV210), it was not easy to see the rear of the distributor where the sensor wires are connected. Before removing the old wires, I looked at the back of the distributor with an inspection mirror and made note of the two white/green wires. Also absent from the documentation was mention of the ground wire.
And be careful when removing/changing plug wires. Don't just pull all of them off the cap at once. Remove them one at a time from old to new.
