US300hp

I read all the posts and articles about adjusting my timing on my 69 corvette, 350/350 rebuilt to factory specs. and I have started the procedures only to see that the mark on my balancer is coming in at the wrong spot with my timing light. Instead of the 1 o'clock position under the tab (when looking at the front of the engine) it is over at the 7 o'clock position. Obviously 180 degrees off. Is there any way to realign the mark without taking off the balancer? I know I guess I could scribe a line 180 degrees across from the timing mark but I don't think this would be too accurate. Any help is appreciated. Thanks.

US300hp

I just realized the harmonic balancer is keyed so it can only go on one way, so what the heck is going on?

my 76 ray

OK. Start with the basics.

Your timing light needs to be connected to the #1 Cylinder. It is the front spark plug on the driver's side.

You are not 180 degrees off. At 180 degrees off the mark would appear at TDC (0 degrees on your timing tab) because the crank turns twice for each revolution of the distributor.

The outer ring of the harmonic balancer may have slipped and it will need to be replaced if that's the case.

morleyz

If it fires up and RUNS, the only thing I can think of is: Are you sure your timing light is hooked to Cyl #1? If you're hooking it up near the distributor, there's no required spot for #1. Whoever installed the distributor could have set #1 to any one of the posts. Set the balancer to 0 degrees, pull the cap and see where the rotor is pointing. That's your #1.

It it won't run, it could be you're 180 off. If that's the case, set the balancer to 0 and make a note of where the rotor is pointing, pull the distributor, rotate the engine 360 degress and put the distributor back in with the rotor pointing to the same location.

US300hp

Ok forgot to say the car runs and drives good. I was just going to tweak the timing for more power and smoother driving. I was definitely on the #1 spark plug line. I had a trick and put the light on the #6 wire exactly across from the #1 and guess what, the timing mark lines up. What do you think? Are the plug wires totally reversed? I just put the mark at 0 TDC and pulled the dist cap. Rotor is lined up with #1.
The part two of this is my initial timing is about 20. Can't get it any lower (I believe 8 is to spec). My total timing is only 25. Couldn't get it up to 36. Any adjustments to the distributer make the car run like poop! Also when I try to read the initial timing the mark is jumping all over the place, the 20 is kind of an average. Why would that happen. Thanks again for anyone's input!!

myk7

Are you clipping on to the #1 wire at the distributor or closer to the plug? Try it next to the plug, front left. Sure sounds like you have the wires mixed up at the dist and you are not getting on the real #1.

US300hp

I'm thinking of rotating the balancer 1 turn, then the rotor will be half a turn (on the #6 wire). Then taking the rotor off and putting it back to the #1. The mark will be back at 0TDC, and the rotor will be at #1. (REALLY at TDC of #1) Does this make sense?

Camivette

It just means use #6 as you're timing mark. Rotor only goes on 1 way

my 76 ray

You would have to pull the distributor and reinsert it with the rotor pointing to #1. Probably not worth the effort especially if you're not comfortable doing it. It won't hurt anything to use #6 for timing.

What concerns me is that you say initial timing is 20 and total is 25. Are you disconnecting and plugging the vacuum line that goes to the distributor and revving the engine so that the centrifugal advance is kicking in?

TimAT

Pop the cap and check the mechanical advance. It could be gummed up or just a little sticky. I'd be pulling it anyway to see if #1 on the cap is really #1 on the engine, it kind of sounds like someone swapped the #1 position just to get it to run.

gcusmano74

The rotor fits on the distributor shaft only one way. Otherwise, you will be trying to put a square peg into a round hole, and vise versa.
Also, the PO may have rotated the distributor and reset the #1 so that the kink on the tach drive cable is minimized. Attach your timing lead to the wire at the plug, not the distributor.

jotto

Is it a new balancer? Sounds like it may have slipped.

76stingracer

Take out the #1 spark plug. (front drivers side plug) and rotate the engine with thumb on the open spark plug hole. Rotate until you feel the compression stroke. Once you feel it check the rotor and make sure it is pointing at the #1 terminal on the distributor and then check where the timing mark is on the dampener. If the mark is not on or near the TDC timing tab mark then the dampener has slipped and should be replaced.