Should I replace the ignition sensor too?

[MrHappy]

Thank you in advance for your answers.

I have a 1991 Sea Ray 225 BR. 5.7 LTR engine. Engine serial number is 0D510869. It has a Alpha lower unit. I've have the boat for 8 years. I bought it with 285 hours. I has 525 hours now.

Lately I have only been able to get 3, 200 RPM's out of her. The WOT is supposed to be 4,600.

I trailer the boat therefor there is no bottom growth.

I thought may be the prop hub was slipping so I replaced it with a new RBX. The prop is 14.5 x 17. I got it up to 3,400 RPM's but not 4,600. I decided to look at the ignition system and the first plug I pulled was cracked. I've pulled three more until it got to dark. I've replace 4 plugs and will replace the rest.

I'm going to replace the distributor cap, rotor and plug wires. Should I replace the ignition sensor too? I've found the sensor for $95.

Also how do you get the rotor and sensor wheel off? Do I have to man handle it? Pry it off? I tried to gently pull it off but no luck.

I do not have tons of money otherwise I would replace with electronic fuel injection. Unless anyone knows where I can get one for a little over $100.

 

[Do Over]

Every post I've read so far here where guys have an issue pullin rpm's its been plugs.....I'd start there before I replaced anything else.

 

[Bt Doctur]

8 years is a long time between tune ups . sesor wheel rotor is remove by using 2 screwdrivers and prying upwards. if that fails ,you break the rotor off.

 

[Gary Hill]

Im guessing you have the Thundervolt ignition? Maybe Thundervolt V? Check all plugs and wires first. You can buy cheap spark testors as well.