Tune Up Question for 5.7L Mercruiser

[pwrplay]

Hi Everyone,

I have a quick question regarding tune up parts for my 1998 Mercruiser 5.7L with Thunderbolt V ignition (serial# OK278885). It has around 250-300 hours on it.

I bought the boat last year and want to give it a tune up (plugs, wires, cap, rotor, fuel filter). The boat starts and runs great, I just want to do the tune up as I don't know when it was last done.

My question is should I replace the Ignition Coil and Ignition Sensor as well? I really don't want to spend the money if they are OK. What is the typical lifespan of the coil and sensor? Is there an easy way to test them?

Oh ya, one other question, does anyone know what the spark plug gap should be for this engine?


Thanks in advance

 

[Don S]

Re: Tune Up Question for 5.7L Mercruiser

My question is should I replace the Ignition Coil and Ignition Sensor as well?

No, they are not replaced unless inop. They live till they die.

Plug gap is on the plastic cover on top of the engine.

 

[pwrplay]

Re: Tune Up Question for 5.7L Mercruiser

Great thanks for the quick response Don. You just saved me $150.00.

Cheers and happy boating.