I like to tinker so I decided to check the timing on my 87 na today. The results were
L1. 17 deg ATDC
T1. 10 deg ATDC

So in the fsm it says trailing should be at 20 and leading at 5 deg ATDC.

What is going on here, why is my leading higher than trailing. What do I do?

I double checked and made sure I was at my leading wire amd trailing with the timing light and all the wires are hooked up correctly.

 

Did you jumper the initial set connector first to "lock" the timing to factory preset before checking it?

The pickup coil on my timing light some times cross-triggers (picks up the energy from the other plug wires) if I don't isolate it from the other plug wires. Also I've read that you should have it as close to the spark plug as it can be without cross-triggering. Also if you have an adjustable timing light you should calculate based on the factory timing marks.

 

I did not jumper the initial set connector, what where when and how do I do that?

The timing light is adjustable and believe or not the yellow and red marks are still there, yellow is more difficult to see but its there. so I am able to adjust the light to get a good reading I think.

 

The initial set connector is to the left of the leading coil. It is the two terminal green female connector. Jumper these two wires with the ignition key off, engine warm. When you're finished checking/adjusting your timing, don't forget to shut the engine off before you remove the wire. I'm not too familiar with adjustable timing lights (mine is from the dark ages and is non-adjustable.) If your timing light is adjustable, I believe you should set the dial to zero.

 

On my timming light there is a dial and when your checking the timing you rotate the **** until the mark is lined up and that tells you your timing, very simple and easy to read.

 

except that it will be wrong.

 

Well then, now what? I am confused now.

 

I was under the impression that I turn the **** until the mark lines up with the notch on the pulley and that was the timing advanced.

 

it would be on a piston engine with a distributor. with a rotary leave it at zero