GM Optispark

Hi Guys,

I was wanting to find out more info on optispark system. Do you guys have a good source for Optisparks if yours goes? Are they different between years or does a unit from a 96 fit other years? I keep reading and hearing horror stories about these things so I've started shopping just in case.

 

Good luck with that...happy shopping:confused:

 

having changed one personally...ill tell you its not that bad. mine (on my 94 caprice) was bad because everything was corroded and we couldnt get the water pump to bust loose.

i reccomend getting an MSD cap and rotor (no difference in the B bodies...only with the z28's and vettes ) the opti itself is a non-wear item.

what you will need to do the job,

2 jugs of anti freeze
1 felpro timing gasket kit (you only need two gaskets from the kit but they arent avail. separaely...but its only $12 for the kit.
1 opti rotor and cap
1 tube of blue stuff (gasket sealer)
1 harmonic balencer puller (can be borrowed from autozone)
1 wrench and ratchet set.
1 gasket and seal puller

what you want to do while you are doing this job but isn't 100% ness..
1 replace the waterpump.
2 replace plug wires.

how to do it:

1. open hood, make sure your on a flat surface and have a catchpan under the front of the engine. also make sure you engine is cool.
2. disconnect the coolant lines from the water pump,then unplug the sensor
carefully unbolt the 4 bolts holding the waterpump on.
3. with a grease pencil mark the harmonic balancer and the stud that it rides on (this is so you can line it up when you put it back on)
4. using the puller, remove the harmonic balancer.
5. remove the old opti.
6. remove the cap and rotor and replace it with new.
7. using a gasket puller remove the waterpump and opti gaskets.
8. using a ratchet head...tap in new gaskets
9. replace plug wires at this point...be sure to number them!
10. install in reverse order of the above! (dont forget to align the balancer!)
11. refill and "burp" the cooling system.

 

Early ones are non vented...the 96 is vented. Be sure to get the right one for your car.

 

actually mike, that is only on the F-Body cars and the Vette...the B Bodies all had vented!

 

My mistake....I was thinking of a guy that got a non vent by mistake for his wagon. BUT....I didn't know that it did not include the B body. Thanks for the info on that, Ian.

 

lots of drama over optisparks,. myths too,. i put one into a bucket of antifreeze for a couple of weeks with the vents plugged,. to debunk the myth that they die if they get wet or the water pump drips on them,.that opti is till going,.ever imagine what the front of the motor is like down low when driving in a rainstorm?? opti,s are usually 100,000mi+ trouble free distributors, IF the vent harness is clear, and venting properly,.
all kids fro sale,. the aftermarkets have worked fine for me,.( i have 5 lt1 wagons,.and numerous engines,.)
http://motors.shop.ebay.com/__?_from=R40&_trksid=p3841.m39.l1311&_nkw=lt1+optispark&_sacat=

Nick

 

Yeah, Nick...it IS just a distributor after all. Most of them will go 100K without a hitch. I HAVE heard some horror stories about certain after market cheapies though. I don't remember which ones caused the problem, however.

 

That's a great detailed instruction on how to change it. Thanks very much!

I see a number of them on ebay. What do you guys usually pay for these things? At the local lordco store, they want $560 for an AC Delco branded one. I have another option locally for a new aftermarket one for under $100.

I don't konw why I'm even thinking about this as I still have to rebuild the rear end of the car.

 

The distributor itself lasts a long time like any distributor ... not mechanical like the old ones....chances are very good that you just need a cap and rotor.

 

with aftermarket ones , a good riule of thumb is to shake it hard when you get it,. make sure the screws aren't out of the rotor,. if you change the cap on yours you'll have fun with the wee reverse torx screw
s/bolts that hold it together,.and remember to add a tiny bead of silicone to seal the new cap,. as i said they need to be watertight,.

rebuild the rear end?? wth?? whats wrong with it? they aren't high on the list of things that fail on these wagons,. basically a 1/2 ton chev pickup rear end,.
nick

 

This one has a noisy bearing in the rear end. I can't quite figure out which bearing but for $150, I can replace ALL the bearings and seals and skip the diagnosis.
I bought the car this way so I knew what I was getting into. Luckily, it already has the transmission rebuilt as that's something I CAN'T do myself really....well, maybe I can...
Anyways, car is in the air with the diff cover off and I'm just about to pull the axles.

 

Real Noisy??
you'll need a press for the carrier side bearings,. or a bearing heater,.use a sharp cold chisel to split 'em off,.
it'll likely be one of the outer axle bearings,.or if it,s towed alot in its life,. it,d be the outer pinion bearing and again you,d need a press.sometimes re tightening the crush collar helps some,.
nick

 

I don't see any evidence of this car towing anything - there's no trailer hitch and no holes in the frame from someone removing a receiver. The car only has 92000 miles on it. I had my mechanic buddy sit in the back and listen to it when I bought it and he thought pinion bearing. It's a steady deep hum while driving that lets off slightly when deaccelerating. Fairly loud but still easily can have a conversation in the front seats - as opposed to the 82 landcruiser I picked up last night with a friend that was so loud that we had to scream at each other
The description of the problem came from the previous owner that they had some noise in the back end and brought it to a rear end shop that quoted them "$1000 to fix it now or $2000 if you leave it and we fix it later" They drove it for a little while and sold it to me. It's hard to now how much damage has been done although here's a picture of the magnet in the diff cover with metal filings - I don't know if these filings have come from a bearing or the gears or what. Any ideas?

I have a bearing splitter here that I was going to try. Worst case scenario, I was going to bring the stuff that needed to be pressed on down to my buddies shop - or I was going to break down and finally buy a press.

 

Ooh, that looks like a lot of metal on the diff. cover magnet. Nick is wealth of knowledge with these cars so you can trust what he says.

On the Opti spark I bought 3 optis from 3 different eBay sellers (can't remember the first, then Chandlermotorsports, last, thepartsladi) and the first 2 died on me. one through a DTC 16, and the other through the rotor off inside the dist. the third one is still going, and that one was bought from thepartsladi on eBay, but I believe that seller is no longer around. In my opinion, use AC Delco or Delpi stuff. So as Nick said check the rotor screws, and better yet take them out and put a dab of thread lock on them.

Correction: The water pump is held in with 6 bolts.

Mike