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Opti failing? Here is why

redeasysport

Well-known member
Joined
Jan 12, 2005
Messages
57
Location
Myrtle Beach
Corvette
1998 Pewter
Let me say first I am in no way associated with dyna spark. I don't have one but when the time comes this is why I will spend the extra money to get one.

One of the most damaging causes for failure of the OEM GM Optispark Distributor is moisture intrusion. We have documented multiple points of potential water entry into the OEM unit from the front, side and back, in addition to the electrical connection itself. This problem is by far the biggest root cause for most other related Optispark component failures. For those interested, here's what we have observed and documented over many parts of both new, used and failed Optisparks. The first potential locations for moisture and oil intrusion of the OEM unit is on the backside of the case through the sloppy bearing bore clearance and the exposed mounting holes that the internal components use to secure them down to the case. Water is also drawn into the electrical connection at the distributor, the silicone rubber weather pack seal in that connector, (especially on cars with age or that reside in extremely hot climates) and both of the silicon rubber perimeter seals on the distributor cap and around the fiberglass rinite insulator. Most of the time this problem occurs right after a chassis bath at a carwash or when someone washes their engine off and the engine will not start, or misfires badly until the moisture evaporates. As soon as the engine is started, accumulated water in small crevices gets drawn into the unit by engine vacuum and the reluctor wheel slings water all over the bare steel parts and electrical components, causing them to corrode and ultimately fail. The reluctor is a stamped, stainless steel component and does not corrode, but the bearing, bearing retainer, retainer mounting screws, optical sensor screws, rotor screws and the EMI shield are bare steel, to which they do corrode badly. Eventually these components scale and start to flake away to where the debris either gets clogged up in the reluctor windows (causing misfire and Hi/Lo Res. DTC's) or it falls to the bottom of the case to which it clogs the vent tube. Once the vent is plugged, soon thereafter you'll start to feel a noticeable misfire and the poor drivability issues will get worse. Engine oil intrusion has also been observed on vehicle's from which the dist. drive seal in the front of the timing chain cover has failed, forcing oil into these open, exposed holes and through the excessive bearing bore clearances...directly into the case and onto the internal components, coating them. The oil/water sludge deposits cling to everything, especially the optical sensor's photo/emitter windows. Rough engine idle, random misfire, backfiring and engine DTC's soon follow. This problem is personified by a high RPM, high output engine with huge, high power ignition systems. How many times have you disassembled a failed Optispark and found water or oil or rust rattling around in the case? Now you know why. We have addressed these areas of deficiency on the OEM Optispark and corrected them in our design. First, all of the internal component mounting holes are blind and do NOT go through the case, therefore eliminating this point of moisture and engine oil intrusion. Second, the bearing and bearing bore receive an industrial sealant coating around them that serves a dual purpose as both a sealant and to add a retentive property to the outer bearing race to prevent the possibility of it spinning in the bore. Since the bearing has a press fit in the bore AND this sealant applied, it will and has not leaked under vacuum testing. Third, we have completely omitted the fiberglass rinite insulator and it's two respective poor silicone seals with our design. Doing so has
completely eliminated one seal altogether from the original OEM design and another potential point of moisture entry. The only perimeter seal that is in our design is for the distributor cap. We have elected to toss the easily deflected, OEM silicone seal in this area, in favor of a Nitrile, re-usable rubber O-ring in it's place that is semi-permanently sealed with an industrial grade of sealant that was spec'ed and purchased from GE Electrical Systems. Fourth, in eliminating the fiberglass rinite insulator with our design, we have also effectively eliminated another point of moisture entry by removing the electrical connection at the distributor itself. Our unit comes complete with a wiring harness that is integral to the distributor and it is sealed with two grommets both on the inside and the outside, including electrical industry grade shrink tube over the top of them. The internal optical sensor connector well is also filled with the aforementioned GE Sealent. Finally the entire wiring harness assembly is attached and GE Sealant sealed to the case by a shrinkable rubber boot that is commonly found in the manufacturing of Formula 1 Racing wiring harnesses. It provides a redundant sealing property, as well as, providing strain relief to wires themselves as they exit the case. We figured that if it was suitable for F1 Racing wiring harnesses to live in the rain, than it would suffice for our application. Fifth, we have relocated one of the internal vacuum venting locations to the top of the unit, which is 160* different offset than the OEM unit. This revised location promotes better internal venting due to cross venting of the case as opposed to localized venting of the OEM piece. This revised 1 o'clock location will not plug up like the OEM unit's vacuum port location, in the unlikelihood of someone driving through very deep water that may partially submerge the Optispark. (I've seen it happen!) We use stainless steel fasteners throughout to eliminate any chance of internal corrosion from moisture vapor that may be present when the engine is shut off. Sixth, we have included a circular, perimeter boss on the backside of the unit that encompasses a Nitrile O-ring that is designed to seal against the timing chain cover. This further adds a level of redundant protection of heavy water intrusion from the backside of the case. If the distributor drive seal in the front of the timing chain cover fails and oil pours into this sealed cavity, oil will not flow into the Optispark case as the OEM unit allowed, because we have added a small .040" weep hole into the 6 o'clock position of the sealing boss, to allow engine oil to flow to the outside of the billet Optispark body. The bottom line is, that there is alot more to this "Optispark" than one might think or see at first glance. We have addressed nearly every possible point of common failure that there has been and corrected those weaknesses with the redesign of our part. We have put a lot of engineering and forethought in the redesigning of this product and we wouldn't bring something like this to market if it wasn't a viable product that will increase ignition durability and performance. I'm not posting here to sell these things, but rather to enlighten the skeptics that seem to feel as if our part is just "pretty" and an "overpriced stocker". You definitely get what you pay for here. If you've held on through this long post, than I thank you for your time.
Cheers!
;)
 
Well the delteq relys on the stock opti emitter which is one of the parts that gets boogered up when they fail. I know they have better charge on the coils but you can buy a better coil to help that. You still have an opti to deal with that is why I guess it will be Dynaspark for me when the time comes.
 
redeasysport said:
Well the delteq relys on the stock opti emitter which is one of the parts that gets boogered up when they fail. I know they have better charge on the coils but you can buy a better coil to help that. You still have an opti to deal with that is why I guess it will be Dynaspark for me when the time comes.

The optical part of the opti usually doesn't fail, by taking the high voltage component out of the opti with a delteq it solves the problem of why most opti's fail. The dynaspark is basically an improved opti but still has the problem of the cap and rotor which is the part that usually fails just like a gm opti.
 
So, the "delteq" is the best choice to replace the Optic Spark?


I'll tell you, my first vette, a 92 Optic Spark's cap was replaced at 90K miles and I replaced the entire unit at 195K miles. Remember the 92 has no vent and, it had no rust inside. (I drove my 92 daily 90 miles a day) My 95 has more chance to develop rust because it just "sits there" in the garage.
 

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