Omni spark timing
Thread Starter
Cruising
Joined: Nov 2005
Posts: 10
Likes: 0
From: Brighton Michigan
Omni spark timing
I have a friend that installed a new OMNI SPARK himself in his 1993 LT1. I went over, it is getting spark to the plugs but no fire. Should he have put the OMNI SPARK on wrong? Is there a procedure that he should of done to make sure the ROTOR was pointed in the correct direction? If so what is the procedure now to fix it? I think he has to take it apart again, but how do you get it timed to crank?
Race Director
Joined: Dec 2006
Posts: 10,383
Likes: 4
The early opti-spark has a tiny key on the shaft (engine side) that is supposed to line up with a groove in the gear (distributor side). The thing about that tab A into slot B business on these older designs is that they don't prevent one from installing it wrong if he pushes a bit on it or allows the bolts to draw the distributor to the timing cover. So, yes, your buddy could have installed the optispark a bit out of time.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
I don’t know of a formal procedure however the basic procedure is to watch and look to see what you are doing. Carefully installing the shaft into the engine and then carefully installing the opti on it the whole key.
It is probably best to turn the engine so when the shaft is installed in it, the keyway is at 12:00. Then set the keyway in the opti at 12:00 also and push on gently. Minimal force is required as it should fall on hitting the timing cover plate flush. The bolts only hold it I place and not pull it to the engine.
It would probably be wise to start the engine for a couple seconds before the water pump is installed. Put on the MAF temporally. If you don’t connect the water temp sensor it will run rich in about 10 seconds but will run. I like to connect the sensor though.
It is probably best to turn the engine so when the shaft is installed in it, the keyway is at 12:00. Then set the keyway in the opti at 12:00 also and push on gently. Minimal force is required as it should fall on hitting the timing cover plate flush. The bolts only hold it I place and not pull it to the engine.
It would probably be wise to start the engine for a couple seconds before the water pump is installed. Put on the MAF temporally. If you don’t connect the water temp sensor it will run rich in about 10 seconds but will run. I like to connect the sensor though.
Melting Slicks
Joined: May 2001
Posts: 3,014
Likes: 18
From: Raleigh, NC
If the keyway wasn't aligned, and the bolts were used to pull the opti to the motor, it's possible that the opti is ruined. I would take the opti apart and check the rotor and wheel for damage. The encoder could also be damaged, but you likely won't be able to tell visually.
You'll need an inverted Torx bit to remove the cover from the opti, I think it's a number 10, but I don't remember for sure. Also, on re-assembly use a dab of locktite on the rotor screws. The screws have been known to work their way out over time.
You'll need an inverted Torx bit to remove the cover from the opti, I think it's a number 10, but I don't remember for sure. Also, on re-assembly use a dab of locktite on the rotor screws. The screws have been known to work their way out over time.
Pro
Joined: Apr 2008
Posts: 542
Likes: 0
From: middle of Illinois
It's an E4 external torx bit, but it's easier to make one than to find one in any tool store around here. Just find a torx screw head that fits (I wanna say it's a 25, but neat may be right with 10) and screw it into a stand off really tight using loctite or superglue, and use that as your opti screw bit. It was much cheaper than the $80 kit I would have had to buy just to get the only E4 bit I have seen in a store.
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Advanced
Joined: Jul 2008
Posts: 76
Likes: 0
From: SANDY UT
this may sound stupid but did you plug the plug wires in and rout them the right way? the fireing order and dis. plug order is not what most sbc guys would think. to make the wires come out on the propper side of the motor. just a thought.
Melting Slicks
Joined: May 2001
Posts: 3,014
Likes: 18
From: Raleigh, NC
You can find the inverted torx on a tool truck; Snap-on, MAC, Matco, etc... I found mine while I was at a GM dealership looking for parts. I saw the Snap-on truck drive by, headed to the shop. I ran out there and grabbed the guy before he left. He had the socket on the truck, it cost me $8.
Thread Starter
Cruising
Joined: Nov 2005
Posts: 10
Likes: 0
From: Brighton Michigan
Hi to all, Thanks but you keep talking about a KEY WAY. This car's OPTI SPark shft had "gear's" at each end. You could put the shaft in any way you wanted to. So how do we get it back into sync with the motor?
Advanced
Joined: Jul 2008
Posts: 76
Likes: 0
From: SANDY UT
not all of the "gear "is the same. its been a wile for me but eather one tooth is missing or there is one thicker tooth on the "splined" part of the shaft. and if you look at the hole in your cam, and int he hole of the opti, you should see the oposite. ther is no " key" like on a crankshaft. ( but our lt1's dont have that as well)
Race Director
Joined: Dec 2006
Posts: 10,383
Likes: 4
Look at this picture:
"You could put the shaft in any way you wanted to"
That is true but there is only one correct way to align the distributor to the shaft. The correct way fits on smoothly. All other ways need a bit of force to make it fit wrong.
The proceedure is to remove the opti, inspect it for damage as written above, re-install it correctly in time with the cam or replace it if the damage won't permit you to reuse this one.
Start the engine for a few seconds 10 or so with no water pump no intake bellows or MAF as a quick test to see if the engine runs before continuing with the reassembly.
"You could put the shaft in any way you wanted to"
That is true but there is only one correct way to align the distributor to the shaft. The correct way fits on smoothly. All other ways need a bit of force to make it fit wrong.
The proceedure is to remove the opti, inspect it for damage as written above, re-install it correctly in time with the cam or replace it if the damage won't permit you to reuse this one.
Start the engine for a few seconds 10 or so with no water pump no intake bellows or MAF as a quick test to see if the engine runs before continuing with the reassembly.
Pro
Joined: Feb 2006
Posts: 543
Likes: 0
From: powhatan va.
I have a friend that installed a new OMNI SPARK himself in his 1993 LT1. I went over, it is getting spark to the plugs but no fire. Should he have put the OMNI SPARK on wrong? Is there a procedure that he should of done to make sure the ROTOR was pointed in the correct direction? If so what is the procedure now to fix it? I think he has to take it apart again, but how do you get it timed to crank?
Thread Starter
Cruising
Joined: Nov 2005
Posts: 10
Likes: 0
From: Brighton Michigan
1) Ok that is clear. So you are saying that there is a corresponding SLOT on the motor side?
Information: The Shaft on the OPTI SPARK did not have any SLOT. IT was continious GEARS. So I wouild have to incert shaft in the OPTI SPARK and mark the where the SLOT was. Then if the answer to #1 above is yes, then I would have to aline that with the motor slot.
Information: The Shaft on the OPTI SPARK did not have any SLOT. IT was continious GEARS. So I wouild have to incert shaft in the OPTI SPARK and mark the where the SLOT was. Then if the answer to #1 above is yes, then I would have to aline that with the motor slot.
Melting Slicks
Joined: Oct 2004
Posts: 2,510
Likes: 4
From: Austin Texas
1) Ok that is clear. So you are saying that there is a corresponding SLOT on the motor side?
Information: The Shaft on the OPTI SPARK did not have any SLOT. IT was continious GEARS. So I wouild have to incert shaft in the OPTI SPARK and mark the where the SLOT was. Then if the answer to #1 above is yes, then I would have to aline that with the motor slot.
Information: The Shaft on the OPTI SPARK did not have any SLOT. IT was continious GEARS. So I wouild have to incert shaft in the OPTI SPARK and mark the where the SLOT was. Then if the answer to #1 above is yes, then I would have to aline that with the motor slot.
Drifting
Joined: Dec 2003
Posts: 1,493
Likes: 94
From: Westfield MA
It's an E4 external torx bit, but it's easier to make one than to find one in any tool store around here. Just find a torx screw head that fits (I wanna say it's a 25, but neat may be right with 10) and screw it into a stand off really tight using loctite or superglue, and use that as your opti screw bit. It was much cheaper than the $80 kit I would have had to buy just to get the only E4 bit I have seen in a store.
http://www.autozone.com/autozone/cat...layName=Socket
$2.99
Melting Slicks
Joined: Oct 2004
Posts: 2,510
Likes: 4
From: Austin Texas
You can get a set at Harbor Freight for pretty cheap :
http://www.harborfreight.com/cpi/cta...emnumber=95178
