How difficult is it to replace the opti-spark module on a 92? What all needs to come out? Mechanic says its a 5 hour job to complete? Is that about right?

 

I replaced the one i my 94 this weekend. Took from 9 to 3 Saturday and from 9 till noon Sunday. Yea I'm old (67) and slow. I also installed new plug wires and new lower radiator hose and of course the water pump. Plug wires for me are harder than the opti. Be sure to use anti sieze on all bolts you put back. I do and the Harmonic basically falls off. I do have the advantage of having done it 3 times before.

 

I have already replaced the plugs about a 1000 miles ago. and I got Accel wires when I got the opti-spark module. Do I absolutely have to change the water pump? I didn't order that......I am strapped for cash seeing that I just replaced the radiator(ac delco).......the alternator(ac delco) and belt......now I just order the opti-spark(ac delco).

 

what all will I have to take off? I know its a pain to get too.

 

Waterpump and the harmonic balancer have to come off.

It's not all that hard once you've done it once.

 

Thank u........does the water pump have to be replaced immediately I mean I wouldn't mind in about a month. But it just seems like the month of July has been a nightmare for me.

 

WP doesn't have to be replaced at all but you do have to remove it to pull the opti. Now since you already have it off you may want to go ahead and replace it but it's not necessary.

You will need new wp gaskets and I suggest using a ton of RTV on those.

 

RTV? sorry i'm still learning the corvetteforums lingo.

 

RTV stands for Room Temperature Vulcanizing, but it's commonly used to refer to Silicone sealants/caulks, including the stuff that's used to form or adhere gaskets in autmotive and other applications.

Here's a re-run of a set of Opti swap notes I posted here some time ago:

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I'd STRONGLY encourage you to NOT install another OEM Opti in your '92. The '92 used the deficient first-generation Opti, and a replacement unit will be as deficient as the one you're removing.

Consider the DynaSpark or MSD as an aftermarket solution that should serve you much better than the OEM replacement.

While you're in there, I'd also highly recommend that you also replace the water pump, serpentine belt, all coolant hoses, and spark plug wires, unless any of these items are fresh. Also drain and/or flush the cooling system (remove the knock sensors to drain the engine block).

If you have a good set of general mechanic's tools, and decent mechanical skills, you can tackle the Opti swap yourself. No special tools are required. Here are a few tech tips I wrote up some time ago about doing an Opti swap:

Get a Factory Service Manual, and follow the procedure it lays out.

A few tips (I'm going from memory here, so I'll probably forget a few things):

Drain the cooling system.

Disconnect the MAF sensor and IAT sensor and remove the air intake duct with the MAF and IAT as an assembly.

Disconnect the ECT sensor and remove it from the water pump.

Remove the serpentine belt and tensioner.

You may find that you’ll need to unbolt the coil/ICM bracket from the front of the right cylinder head. I can’t recall for sure whether or not I did.

Unbolt (but don't remove) the power steering pump. This will help you to sneak the new plug wires in/out behind the pump, but may also be somewhat helpful when working on the water pump/Opti.

If you want more room to work, you can remove the radiator, but it isn't strictly necessary, and it involves considerably more work to remove it (I left mine in place).

The FSM will tell you that you need a special Kent-Moore puller to remove the crank pulley/damper. You don't. Here's how to get it off:

1. Raise the front of the vehicle enough that you can get under the car (it's also helpful to have it at a more comfortable height while you're working from above).

2. Remove the three bolts that secure the pulley/damper to the hub.

3. Mark the damper and hub so that you can easily see how to realign them to each other later.

4. Slide under the car with a long pry bar or hardwood dowel (I use a jumbo Snap-On screwdriver that's around two feet long) and a mallet.

5. Place the tip of the pry bar against the rear face of the damper, as close to the hub as possible (Ideally rest the tip alongside of the hub).

6 Give the pry bar a few whacks with the mallet, and with any luck the damper will pop off without too much of a fight.

You may find it helpful to apply a few whacks, then rotate the crankshaft in 120* increments, whacking it a few times at each interval (I haven't needed to do this).

It's also helpful to, if possible, shoot a bit of penetrating oil where the damper meets the hub, a day or more in advance of doing the job.

After you get the damper off, clean the damper/hub mating surfaces to remove all corrosion, etc, and apply a very thin coating of anti-sieze compound to these surfaces before you reassmble the damper to the hub. This should make it a lot easier to get the damper off next time.

Once the damper is removed, rotate the crankshaft so that one wing of the damper hub is at the six-o'clock position. This will position the other two wings at around the ten- and two-o'clock positions. In this orientation, the Opti will clear the hub as it is being removed/installed.

The Opti basically unbolts and pulls off as you'd expect, once you have the water pump and damper out of the way.

Once the Opti is out of the way, inspect the shaft seals for the Opti, water pump, and crankshaft. If they show any signs of leakage, replace them now.

When you install the new Opti, be sure to align it correctly with the cam gear, and don't force it into place against the timing cover (do NOT use the bolts to draw it into place). At most, give it a gentle bump with the heel of your hand to encourage it to pop into place.

Reassemble everything else.

Follow the cooling system refill procedure in the FSM carefully, and you'll have no problems with this. In particular, be sure to bleed the air out of the system as it's being refilled. I recommend that you also re-bleed the system after the first three thermal cycles.

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Hope this helps.

Be well,

SJW

 

That will be a tremendous help. THANKS ALOT!!

 

You're most welcome. That's what this forum is all about. Most of us are happy to help out when we can.

Good luck with the swap. Let us know how it goes.

Be well,

SJW