In an attempt to remove a misfire and a code 16, I will be replacing an OEM optispark with a MSD unit. I replaced the original optispark when the engine was out of the car but now that the engine is in, I need to schedule a time to tackle the dreaded project. So how long would you assume a partially, mechanically inclined person could replace? And interrupt if this order is incorrect.

Disconnect the battery, remove air intake, remove A/C lines, drain coolant out of block by knock sensor. Remove hoses connected to waterpump, remove belt, remove waterpump, remove idler pully, remove balancer then you have access to distributor.

 

I'd strongly recommend that you also replace the water pump, all coolant hoses, spark plugs and wires, and serpentine belt, unless any of these items are fresh. You'll never have a better chance to replace these than when you're already into things as deeply as is required to replace the Opti.

Here's a list of tips I wrote up some time ago about doing the 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.

Unbolt the coil/ICM bracket from the right cylinder head.

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 (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 cranshaft. 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.

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.

Hope this helps.

Be well,

SJW

 

I did the waterpump, opti, plugs, wires, & coil in about 4 hours. This included a few beers & time to let the coolant drain out.

Enjoy!

 

I'd say it will take you every bit of 8 hours the first time....

 

SJW has the best reply I've ever seen for opti replacement. It will take a considerable amount of time. I think I had 3 hours just changing the plugs.

 

Wow i'm glad I have an L98, that looks like a lot of work.

 

Did you have any problem getting the opti to seat..did you have two Orings on the opti shaft, did you have to remove them to get the opt flush...I cannot get the Opti totally flush as for the last 1/8th of an inch. Thanks for any input