I know this sounds like a dumb question but im new to the vette scene, I recently purchased a timing light to complete the tune up process on my 89 coupe (stock engine Cat back Exhaust) but i dont know where to look for the indicator. and the manuel doesnt help me very much. Can somone explain the process to me and if needed how do I make timing adjustments.

Thanks in advance!!!

Kevs_l98

 

Stand on the driver's side of the car at the front of the tire facing the engine.

Then look down below the water pump toward the dampner to the timing chain cover. On the cover, at about the 2/3 o'clock position you'll see a timing tab. That's where you shine your timing light.

The tab is usually covered with crud, so it's a good idea to clean it before firing the engine.

The tab has a ZERO point indicated on it and a series of hash marks and numbers too.

Everytime the timing light flashes, a groove cut into the dampner will align with one of those numbers; the number it aligns with tells you what the amount of timing advance is.

Make sure you disconnect the EST conector FIRST though. This disables the computer from taking over the timing and must be done before you set/check the initial timing setting.

Disconnect the EST with the ignition "OFF" and, also reconnect it with the ignition "OFF". You'll have to disconnect the battery for about 20 seconds or so after you're done to clear the error code that gets set when the computer detects the engine running with the EST wire disconnected.

In order to adjust the timing, it's easiest if you have a distributor wrench which is available at most auto parts stores for a few bucks. It's 'L' shaped to allow access to the single bolt that holds the distributor clamp in place. The hold down bolt is 3/8" diameter with a 9/16" head.

All you need to do is loosen the distributor clamp bolt (you access it from standing on the passenger side of the engine) which is just under the distributor. Loosen it just enough to allow you to turn the distributor. As you turn the distributor, the timing on the engine will change.

6 degrees of advance Before Top Dead Center (BTDC) is the stock setting.


Hope this helps.

Jake

 

There is a groove cut in the vibration damper that will align with the timing tab on the left side of the timing chain cover. There is an illustration in MY service manual. Except for being in a Corvette chassis, it ONLY a small block Chevy engine. Of course you have to disconnect the ESC wire near the brake booster, but surely you read that.

RACE ON!!!

 

Stand on the driver's side of the car, facing the engine right at the area of the front tire.

Look downward, below the water pump to the area where the crank pulley/dampner and timing chain cover are.

On the timing chain cover there is a timing tab. It'll have a ZERO indicator on it, along with a series of numbers and hash marks. That's where you point the timing light when checking/setting the initial timing.

The tab will probably be covered with crud, so it's a good idea to clean it first. Also, be sure to disconnect the EST wire (brown wire with a black stripe right under the power brake booster) before you begin.

This will disconnect the computer's timing control and allow you to set the initial timing. When you're done, shut down the engine, reconnect the EST wire, and disconnect the battery for about 30 seconds to clear the SES code.

The computer automatically sets a code when it detects the engine running with the EST wire disconnected.

Hope this helps.

Jake

 

Good detailed advice. If you can, try and find the timing mark (should be a slot about 1/16" ) cut into the damper. I use paper white out in this slot. This makes seeing the timing mark much easier. If your timing light has a timing advance dial on the back it makes it much easier to set the timing. If you have this, just line up the timing mark with the largest or deepest slot by using the dial. This will tell you exaclty what advance you have. Turn the distributor a little at a time and recheck the timing until you get it where you want it. Tighten the distributor and recheck the timing to be sure that you have not moved the distributor when you were tighting the bolt. If you can get someone to help, have them turn the distributor while you check with your light. Four hands REALLY makes this easier. It is not hard, so don't be afraid to tackle the project. I know you will do well. It is always great to know that you did it your self and it works.