Tom400CFI

The Opti has higher resolution than the DIS systems of the time (and now, even) = more accurate timing...so they say. I question it some, b/c there is a timing chain between the crank and the cam/crank sensor. My understanding is that this timing accuracy was necessary to meet the power/emission requirements for the LT1. IDK for sure though. GM wasn't alone trying this philosophy either; I've worked on mitsubishi's and Nissans of the era (and newer) that used the same kind of optical ignition system. In the end the philosophy lost out to magnetic pick ups on the crank/cams.

Renfield

Okay, I'm going to need another tool. No surprise there. The cap and rotor arrived, so now the pressure is on. This is becoming quite a sweat fest.

I don't see why anyone would pay for a tattoo, all I have to do is turn a wrench and my arms look like Gorbachov's face.

Good point about hammering against the crank. Not a lot of room for a puller though. I'm still three bolts away from that process. I had no giddyup left yesterday after work.

Here are a couple snaps of the mess so far. I miss my ride.

grandspt

I know your pain believe me, although my arm didn't look that bad yikes.
Your Opti looks worst than mine, it is really covered with crud. Mine had a lot less (probably the lack of miles).
The plug wires are another pain your arms will get worst.
Keep up the good work but give your arm a little break

Renfield

Yea, I can't believe how thin my skin has become. I need kevlar sleeves. The only part of getting old that doesn't suck is knowing the alternative.

Mine had 86K miles on purchase in September '15. Sitting near 95K now. So about twice the miles (twice the crud?) as yours.

What amazed me was that the flood of dexcool seems to have missed the Opti. Or at least I can fool myself into thinking so for now.

Did your cap and rotor set come with any gaskets or seals? Maybe this is why people write about using RTV?

When I finish getting Lucy back together, Polo Loco is up next!

All the best!

grandspt

Yes, my cap and rotor kit comes with the cap, rotor, middle cover (with impregnated gasket), 2 small O rings, and screws.
When I was younger it never
bothered me working under the hood but now approaching 53 years I feel more body pain But you are right it is much better than the alternative.
Tomorrow I shall see how far I get with my repair, I hope it goes smoothly.
And again I wish you the best with your repairs too.

Renfield

Okay now I am really upset with Corvette Central. They shipped me a non-returnable item without the stuff to use it. Here's your cap and rotor, sucker. Try finding what you need to install it. Nice.

Ah, to be 53 again. The scary part is knowing that I will look back on 58 fondly some day. Soon.

chstitans42

Keep it up! Itll go back together faster than it came apart! What parts did Corvette Central not ship to you?

grandspt

Update, I got my balancer/pulley off and I had to resort to the BFH and a long 1/2" drive extension. I couldn't get any kind of puller in there and make it work. After a few blows it did fall off after hitting the balancer/pulley in one spot and then 180 degrees on the opposite spot and more PB blaster.
What a pain in the ****!! That sucker is going to have plenty of antisieze when it goes back on.
So the bad news is I tore a boot on my new MSD wires (opti side) and on one of the other wires the terminal stayed in the Optispark
I ordered a new wire set and they are not MSDs instead they are Taylor wires from Summit for $65.95 + handling fee.
After pulling the Optispark apart I found one rotor screw sitting in there and the other rotor screw loose. This had to be my misfire and I am surprised it ran and never threw a code. The rotor was in bad shape and so was the cap. I could not find any real signs of moisture thankfully! But I continued to disassemble the Optispark, the bearing seemed good not muck side to side or any forward and back play.
The Mitsubishi Sensor was clean I took a little shop air to gently blow it out but overall the optical side looked clean.
So my missing under load was probably the screw that fell off, the rotor being loose and I am sure the crappy MSD wires were not helping either ( I had problems with the coil wire that came with the MSD set in that it would not click properly I had to expand the spring contact to make it work) MSD seems to have gone down hill in quality.
And for peace of mind I am changing the vacuum lines for the vented portion of the Optispark.

I hope your project is going better than mine.

chstitans42

grandspt:
Mine was doing the same thing. Got a random misfire code. Eventually both of my screws that held in the rotor came out, and then the car would not start.

grandspt

chstitans42, thanks for the info at least I feel confident that the replacement cap, rotor, screws will cure my problem.
The GM kit came with rotor screws with a little bit of blue loctite on them. I am going to use red loctite just to make sure this doesn't happen again.

grandspt

Did any one have a problem pulling the balancer/pulley up and out of the way (even with the opti removed). Mine kept interfering with a small raised stud on the steering rack and of course the hub.
I took my air grinder and shaved the stud on the rack down so I could gain clearance to slide the balancer/pulley up and out.
I wanted to paint the balancer black and put antisieze on it

Renfield

Nice work there grandspt! I wanted to see the puller you got to fit.

chstitans, here's what Corvette Central shipped.

The label is truth in advertising. "USER: SAD"

Renfield

Here's a noob question. Do I need to mark orientation on the balancer so it goes back the same?

Plugs and wires came yesterday from Rock Auto. Aptly named as they truly rock. I bought the Denso wires in boring black and the Denso platinum plugs.

grandspt

Renfield, I did not need to mark them on my LT4 the balancer/pulley had an arrow on the front and the hub had a matching arrow. I also believe that the bolt holes in the hub are oriented so you can only install it one way. Take a look and see if you have the arrows.

chstitans42

Yes the balancer can only go on one way

SJW

Red Loctite is overkill, and you'll curse it the next time you need to replace the rotor. It must be heated to break its bond. Don't go there. Stick with the blue Loctite 242. It's more than adequate to secure these small screws.

Live well,

SJW

SJW

I have not had a problem sneaking the damper out without using a grinder, but it is a close fit. It doesn't shock me to hear that there might be enough variation from one car to another to cause a clearance problem.

Live well,

SJW

grandspt

Thanks SJW for the tip, although the next time it needs replacement it will probably need a new optispark anyway

richcory

My 94 is going in for a new MSD opti on 2 Sept. I had the current MSD opti installed in 2010. Early this year it started not wanting to start with really long crank times. Then it started randomly dieing while idling. It died once at about the 1000ft mark on the dragstrip. I pulled the codes and it had the opti code.

If I had a lift I would like to do the job myself. Thanks to the OP for posting the video.

chstitans42

You don't need a lift. it is all 99% from the top end. Don't waste money paying someone else to do a job you can do!