Hey Folks, working on a 96 Z28 replacing the radiator and water pump. The vehicle is a 96 approaching 100K miles. Should the distributor cap and rotor be considered while it is apart? I know the standard cap and rotor should be replaced on a regular basis but not sure on this stye engine.

What is the change interval recommendation?
What is best practice?

I don't want to steer the owner in the wrong direction but also don't want to have to pull this apart again in 6 months when it can be done now.

Appreciate your feedback.

 

Like any distributor the Opti cap & rotor are a wear item and should be replaced at 100k mi. Pic looks to be a original AC Delco opti. DO NOT replace that opti as all remans are sketchy. A new C&R with brass terminals would be a prudent decision. You may discover some oil and or coolant inside the opti once you do remove cap & rotor. Just carefully clean it with Q tips or something prior to reassembly. Use blue loc tite on the rotor screws and apply a skim coat of dialectic grease on the large O rings for the cap before cap install. Also on the rubber seal of the large 4 pin electrical harness that plugs into the opti

I would also highly recommend you replace the WP drive & opti seals. They are both PTFE seals and install dry. The FelPro timing cover seal/gasket set for $12 is available at any parts store. You do need a "tool" either specific or home made to install the water pump drive seal so the inside lip does not fold under (99% chance of hat happening without using a tool). Generally these tools are about $20 on ebay or the cap from a Sharpie pen can be used

While the MSD C&R is/was considered very good this one from rockauto is good
https://www.rockauto.com/en/moreinfo...049701&jsn=443

WP drive seal install tool





The Damper hub on crank seal should be fine but if signs of it leaking you should replace. It comes in the TC seal/gasket set. No need to remove hub if just servicing opti. Just unbolt damper from hub. If the rubber is cracking on the damper, replace it

The WP drive seal is a very common leak source so do replace it and if the O ring on the Opti and drive spline are cracked replace those and grease the inside of the spline coupler. If you ignore this the spline coupler will vibrate slightly quickly causing the WP drive seal to leak.

Leaking WP often contaminates the Opti so when you do swap out the C&R clean the inside of it f that happened. The sensor in original AC Delco is why you want to keep that AC Delco opti (Mitsubishi)

 

Thanks, going to order the C&R along with new seals. The seals seem fine, no sign of any leaks at all. I know the standard cap and rotors get replaced with the ignition wires or at least I always have, but hate to install a new pump just to have to replace the cap and rotor 6 months from now, from a labor perspective it doesn't make sense. It would be an added 4 hours to replace it alone.

I do see that there is 2 different caps, one with and without Mexico Emissions, any idea on if there is a difference? I am in the USA but not sure if there was a difference, can't see why where would be.

Appreciate the feedback.

 

Where are you seeing these two caps? I've been dealing with these parts for 20+ years and never heard of one for “Mexico emissions”.

There is a cap for the unvented 93/94 Opti, without the vent system nipple, and one for the vented 95-97 Opti, with the vent system nipple.

 

I checked Rockauto and yes, I do see for the same year a vented and non vented option not sure why they would show two different caps for the same year. They also have a note for 'Mexico Emissions' which is not something I've seen before.

See pic below:

 

They get the years mixed up sometimes because the F-Body an Y-Body LT1 went vented in 1995, and the B-Body went vented in 1994. On an eBay listing for DR473 they show a note regarding “MEXICO EQPD” for the 96 Corvette and 95 Camaro applications only. Again, no idea what that’s all about.

The vents get confusing as well.... MSD replacements for example have the vent nipple on all years.