Vortec 454 Cap and Rotor Replacement

[EmersonHart13]

I am guessing James knows the answer to this... lol

Does anyone have a how to for the cap and rotor on the Vortec 454? It is buried behind the motor and and I would love to know what I need to do to get to it.

Thanks in advance,

John

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[jason05gt]

I just replaced the cap and rotor in my boat which has a GM/Mercury Marine 454. The cap is held on by two phillips screws. Make sure to mark the wires so that you do not mix them up. The rotor is under the cap. It's keyed on the shaft and slides right off/on. Put some dielectric grease on the contact so that it will come off in the future. It's about a 15 minute job on the boat, but might take longer in an engine bay due to space.

 

[Eagle]

Start digging! I didn't even think they still had dizzys in these things!

 

[EmersonHart13]

Eagle Ill post photos! It is so buried!

Jason what year is your motor? I am guessing that doesn't have PCV or EGR, right?

I have a pretty good feeling all or most of the ignition system is original with 162k miles... ewww

 

[EmersonHart13]

Dizzy:

Plenum Height:

Cap under there:

Passenger Wide Shot:

Old Plugs:

While I have all this apart I think I am going to try to clean the IAC, EGR, MAF, and TB. Also I will replace the PCV. I think the front O2s should probably be done, but I am going to order those online.

It's a pain? I'd say it's far more of a pain to remove the intake when there's absolutely no reason to do that just to change the cap and rotor! 1998454 - Are you kidding?

Two bolts and two harness connectors get the coil/ignition module off the back of the plenum and out of your way, then the cap and rotor are totally accessible.

Yes, you have to lay down across the top of the engine to do this, but it's really not that bad.

EDIT - this always bears mentioning when discussing replacing a Vortec distributor cap - RE-USE YOUR OLD SCREWS. Replacement caps often come with threadlocker on the screws or may not be the "exact" correct thread; it's very easy to break the plastic tabs on the distributor body where the cap screws on. It doesn't need any help from funky screws.

 

[EmersonHart13]

Ugh... I think this is going to require removing the upper plenum. I changed the wires today and even hooking those up was terrible. Even though people say it is possible to change the cap and rotor with the plenum on, I do not think I am able to do it. I guess I will have to make that a Saturday project. On a bright note changing the plugs and wires have smoothed out the idle. Now it just has a small shimmy at idle after getting warmed up and that could very well be related to the cap and rotor.

 

[jason05gt]

Eagle Ill post photos! It is so buried!

Jason what year is your motor? I am guessing that doesn't have PCV or EGR, right?

I have a pretty good feeling all or most of the ignition system is original with 162k miles... ewww

It definitely has a PCV. It's a 2001 Mercury Marine 454. I am not sure about an EGR though.

 

[Turbocharged400sbc]

have fun, no you dont have to pull; the upper intake but if you do pull it you might as well replace the LIM gaskets while yer there

 

[EmersonHart13]

Yeah, that is why I don't want to. I found out the secret to getting that back coil bracket off is a wrench with a bend or offset in it. I am going to give that a try because a straight wrench was not working for the driver's side nut.