Use this guide at your own risk I am in now way responsible if you screw up your optispark.

Hey guys as some of you know I had some ignition problems lately it turned out to be the coil. When I had the car apart I took the opti apart and decided to make it a vented style unit per this article www.corvettefever.com/howto/16758/ . I did some things different too. Here are directions to what I did. I tried not to repeat any of the information mentioned in the links I have you guys.

Items needed.
T8 or T9 screwdriver for rotor bolts.
4mm Socket
E4 Female torx bit. ( I couldn’t find one so I took an old TB Bolt and welded a nut to the end of it.)
Red Loctite
Dremel + Wire wheel + sharp pointed grinding stone
3/16” drill bit
T-Fittings
Vacuum hose
Permatex Ultra Copper RTV
409 Cleaner
Isopropyl alcohol
A can of black spraypaint
Lots of Q-tips
Lots of paper towel
Black Sharpie



1. Disassemble the opti. The 92-94 style units have a little more guts to them than the newer ones. There are some male torx bolts in there. You can use a 4mm socket to take them out. Just be careful and take your time. Refer to this page. http://www.charm.net/~mchaney/optisprk/optisprk.htm One major area that's different with our opti's is the way the slotted disk sits on the opti drive. Ours are spot welded on. I couldn't get the metal to drill so I used a sharp tipped grinding stone in my dremel. Before you take this off clean the surface and mark the holes with a sharpie this will help you make sure that you line it up right when you put it back together.

2. I noticed all the metal internals had surface rust and oil on them. I cleaned everything off with 409 then I cleaned them all up with a wire brush in my dremel. I then cleaned the surfaces with isopropyl rubbing alcohol. I then proceeded to paint them flat black. I chose a dark color since optical drive manufacturers noticed that this helped there drives read disks better since there was less reflection inside the unit when closed. I don't know if it poses any benefit to this application or not. Do not paint the optical disk!!!! Also leave the stainless guard alone just clean it up.

3. Everything inside was cleaned with 409 then with isopropyl alcohol. I used a lot of q-tips to do this.

4. I took out the screws that keep the Mitsubishi optical sensor fastened down. I slightly bent up the sensor so a q-tip could fit in there. I cleaned it off with the alcohol and then blew it off with compressed air.

5. Reassemble all the opti guts. When you go to line the slotted disk back up dab some loctite on the back of it. And line it up with the holes and sharpie marks you have from before. Push down slightly to spread out the loctite and let it sit for an hour. I did this to make sure it didn't move when I was putting the rotor back on.

6. Now you can put the rest of it together. I threw out the cracked stock seals and used permatex ultra copper to hold everything together and keep this thing water tight. I've never had a problem using this. To promote better adhesion to the plastic on the cap I roughed it up using the wire wheel again. I also cleaned it all off with the alcohol.

7. My cap and rotor were pretty new so I reused them. I put loctite on the rotor screws to make sure they don't back out. I cleaned the rotor up a bit with the wire brush along with the internal terminals on the cap.

8. Put it all back together now. Tighten everything up. Let it all sit for 24 hours so the rtv can properly cure.

9. Put it back on your car. Cross your fingers and turn the key. Mine started right up. It seems a little more responsive now than before. That could be due to cleaning the rotor and terminals plus the new coil I put in.

I didn't take any pictures my garage is to dirty to have my camera lying around in there. I may make a better step by step guide down the road with pictues if I can find a non-vented donor opti.

 

Not too shabby
Any idea where to find a replacement Mitsubishi disk?

Now all you need todo is market this and start rebuilding optis

 

What, if anything did you do to the harness connector "tower"? There is some evidence to suggest this is one of the main channels for moisture to enter.

 

The opti disk shouldn't go bad. It's stainless steel the only thing is rust particle can clog it up. This can be taken car of by a cleaning. The optical sensor seems like it should be a stout unit as long as nothing blocks the optical "lens" I have no idea where you could find one of these. I think that with a careful cleaning you could repair a lot if not all opti's that throw high or low resolution codes. The only hard thing to find would be a source for bearings. The oil that gets into the opti comes from the bearing itself. Rust particles shouldn't be a problem now that all the steel is properly painted.


Injuneer you are right, that is the main channel for moisture to get into the opti. It's a really bad design as far as I’m concerned. My tower was actually cracked none of the connections inside were stressed though so I plastic welded it back together. I cleaned the old foam gasket out completely with the wire brush. I also used an abrasive to rough up the service of the housing and the tower. I carefully filled it with rtv before I assembled it back together. The opti vacuum harness has a flow regulator so it won't see near the vacuum pressure as a regular vacuum port. The rtv if prepped properly should have no problem holding. It would be better if the case was a tighter fit to the connector but I'm not worried about it.

One thing I don't like about the 92-94 style units is the optical sensor is located on the bottom. Where as the 95-97 has it on the top. So any oil that leaks out of the bearing will drain down onto the sensor. I was surprised mine still worked it had a healthy coating on it.

 

kinda off topic but...DAMN...that's quite the car collection you got there

 

Thanks, I worked 60 hours a week during my summers in H.S. in a stone quarry. While the other guys in my class were buying weed and pissing away their money on other stupid crap, I bought cars an messed around with them. I need to start getting rid of a couple of the newer cars so I can put more money towards the older ones. They were a good investment though I always have people coming up to me at shows asking If I want to sell something for a lot more than I paid for it. Once I get done with my bachelors degree and get a decent engineering position someplace I'm going to fix them all up really nice.

 

A few points based on my experience with early opti s:

All the rest is good info..
I did chase down a bearing once but it was very hard to get[like impossible] and VERY pricey...
Also on that 'to do ' list is to try to bore that housing out a bit and put in a REAL bearing...[sealed ball, etc..] to replace that so called 'bearing' that comes stock in one.. I believe that would be a real improvement..
Charlie

 

I agree on the bearing. What are the other points? They got cut out of your post.

 

The points are there, just inside your text..I edited and made my comments BOLD
Charlie

 

the Same thing to mine a while back. I also cleaned the harness that plugs into the opti. I always had problems with this. I used some Dielectric grease and some rtv around the top to seal it off. havent had a problem to this day and I have even washed the motor since and still no problems.

 

Haha I didn't even see that. Good points Charlie. I could not get that disk off though when I tried wiggling it back and forth.

 

Has anyone tried using an opti without the tin EMF shields inside? wonder whether it would work and what the result would be.. that would get rid of a lot of the rust problem inside.. There are electronic distributors out there that do not use that.. hmmm

 

I have a powder coating kit. The next one I'll powder coat the shields then they'll never rust.