Optispark questions

[Veronica Mangan]

I also have the classic wagon, and am having to R&R the water pump. Have removed the water pump, and also thought I might as well replace the distributor while I was at it, so am glad to get all the info. I'm under the impression that the "distributor" is all one piece. I also have the Chevy shop manual, which does have helpful info in addition to the Haynes, which is pretty brief...but any additional info, or links to pictures, would be appreciated...
Veronica.

[Veronica Mangan]

[quote=j cAT;6479987]If you look this up on the internet search you will find many pictures and details on removing this water pump and replacing the cap/rotor, and if necessary the distributor..

can you give links to these pictures and details?
Veronica mangan

[Blue Bowtie]

The OptiSpark (Opti) unit itself is held on with conventional fasteners. The Opti distributor cap is held to the shell with external Torx screws (E4 socket). In my opinion, it is far better to remove the Opti unit completely, then remove the car and rotor for replacement. That is the only way to effectively and safely clean the unit, including the interruptor disc and optical pickup array, and verify the correct placement of the seals upon reassembly. It also lets you clean the electrical connectors to the Opti unit thoroughly and allows for a good look at the seal in the timing cover.

Once the water pump is removed the harmonic balancer accessory drive belt sheaves must be removed. Your wagon likely has the heavy duty cooling option which included a belt-driven fan and second drive belt for it. That drive sheave must be unbolted and removed to allow access to the damper bolts.

NOTE: Before removing the damper from the hub, match-mark the position of the damper in relation to the hub. There have been numerous discussions about whether the hub/damper are balanced as a unit or individually. Since no reliable answer has ever surfaced, it is a good idea to reassemble them in the same orientation they were originally assembled. It is also a good idea to note the position of the arrowhead cast into the hub and install it back onto the crankshaft snout in the same orientation when reassembling. (The arrow has been painted white in the photo.)



When the damper has been removed the Opti can be removed and clear the hub. If you find that difficult because of the accessory setup, you can remove the hub by removing the center bolt and using a three-jaw puller.

Once removed, the Opti is fairly self-explanatory, but there are some tips which might be useful as a guide. I'll try to post them shortly.

[Blue Bowtie]

There are some helpful photos and ideas to be found HERE .

Remember that it is important to clean and thoroughly dry everything without the use of compressed air. The optial pickup array can be safely cleaned with a tissue or swab soaked with isopropyl alcohol. Methanol, mineral spirits, and stronger solvents can attack the plastic and optics and should be avoided. Allow the parts to air dry.

Verify that the ventilation system is working. All the vacuum hoses should be intact and the check valves need to be functional. The air supply tube also needs to be connected and intact. These are critical in keeping the Opti clean and dry while in operation.

I had good success using aftermarket caps and rotors. My own '94 has a Borg-Warner cap/rotor set on it which has been flawless since June of 2000.