95 Opti Cap Replacement

[Zo6 LVR]

I replaced my plugs with AC Delco replacement plugs and shortly after developed a miss at idle in gear with the A/C running. The miss is random and is also there without the A/C on but much less noticable. I assume due to the extra load of the A/C it is more noticible. Because I just replaced the plugs my first thought would be a bad plug or improperly gapped plug or a bad plug wire that was disturbed when removed and replaced from the plug.

Does anyone know from experience if it necessary to remove the water pump to replace the distibutor cap? Or is there a procedure out there for replacing the cap?

 

[WillC4]

On an LT1, yes it is necessary to remove the water pump. Also need to remove, or push it forward enough, the harmonic balancer. I just recently did a complete tune up on my '94 LT1. My biggest complain is the harmonic balancer removal. Not much space to work with, especially with that "cross brace" in front of it. I actually couldnt remove the harmonic balancer, but was able to tap it forward enough to slide the new distributor in. If your not replacing the whole distributor, i suggest covering it with alot of towels to keep coolant from reaching it. It may also be beneficial while your at it to replace the spark plug wires as well.

 

[Zo6 LVR]

Thanks Will. How many miles on your 94?

 

[C5sarge]

When I replaced the opti on my 93 I took an old wooden solid broom handle and positioned it going forward behind the right front tire. I got the end of the broom handle behind the balancer and used a 5 pound hammer to hit a few times. Then I would rotate the motor 1/4 turn and do it again. After about 10 times the balancer popped right off. I know they make pullers but the area is so tight and hard to get to without a lift.

 

[gmjunkie]

LT1 and LT4's have a 2 piece balancer,3 bolts around inside of pulley and it will pop right off the hub!!

 

[WillC4]

Im sitting at about 131k miles on my '94 now, with the distributor being replaced with a MSD unit, Moroso 8mm wires, ACDelco Plugs, and MSD Coil as part of my tune up. I also replaced my water pump with a Duralast unit, ACDelco 15 pound radiator cap, and ACDelco 180° T-Stat. That was done maybe 300-400 miles ago.

Now for the process, people do it differently here and there (not too much though).
This was my process to get to the Distributor:
-Disconnect (-) terminal of the battery.
-Disconnect MAF and Water Temp sensor wires/connectors
-Remove Intake Neck (between Intake and Throttle Body)
-Drain the Coolant system (drain plug located on radiator, lower passenger side)
-Place Plenty of Towels above and around the distributor (if your reusing the current unit)
-Unplug all coolant hoses attached to the water pump (Coolant MAY and probably WILL spill out, so be prepared)
-Remove Water pump (six bolts, three on each side, there may be a bolt where you will need a flexible/angled extension to remove it, the one located behind the power steering pulley, again coolant MAY and probably WILL spill out from the engine block, so be prepared again)
-At this point, the distributor/opti will be visible.
-Remove the Harmonic Balancer, (3 outer bolts and a single center bolt)
-From here Distributor is accessible, whether you replace the whole unit or not is up to you.
-Reverse process when your finished with the distributor, be sure to torque the bolts to proper specs and refil your coolant system,

*on a side note, there is a sleeve that attaches to the Water Pump gear and Timing chain gear, KEEP THIS, you will need it. You may want to clean it out with penetrator spray, or WD 40, then add grease to it. I used a $2 packet of bearing grease on it from autozone with plenty left to spare.
** You may also want to replace your spark plug wires while the distributor is accesible.

If there is any additonal questions, comments, concerns, additions to this process, please feel free to add to the discussion.
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