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Wed Feb 22, 2023 1:29 pm

I wonder if anyone can help me with a timing problem which has really got me puzzled. My car is a 1973 1303s fitted with an AJ code ex fuel injected engine. This was converted to carb before I got it. It has an electric fuel pump and a Pict 34 carb. I'm aware that with the 009 distributor the timing should be set with the engine running at 3000rpm and should be 28 to 30 degrees btdc. To get the engine running though I had to get the timing somewhere near. Therefore I set the static timing at 8 degrees BTDC. I started the engine and it ran fine, both at idle and upon accelerating. I then put my timing light on (correctly with inductive pickup arrow pointing to the plug on number 1 lead) and to my amazement the reading at 800rpm idle was 38 degrees. Revving up to 3000rpm the reading went up to 58 degrees. So that's obviously 20 degrees advance, which I believe is right for a 009. But why those readings? Why not 8 degrees and 28 degrees? It's really got me beat. I've checked the crank pully and the marks engraved upon it and that's all correct. Any ideas will be most gratefully recieved.

Wed Feb 22, 2023 1:46 pm

I would guess that if the idle timing was actually 38 degrees BTDC, the engine would be hard to start.

Are you reading the timing from an aftermarket pulley with degree markings on it, or are you using an adjustable timing light? If you're using a degree-marked pulley, double-check that your timing light is set to zero (if adjustable). I put tape over the knob on mine to keep it from turning accidentally.

Being off by 30 degrees shouldn't be a wrong-wire issue, because as you move the sensor to different wires, you should see the timing shift in multiples of 180 degrees (or is it 90? but anyway, not 30). Once I got the number-2 wire by mistake and saw the bottom of the pulley illuminated (the PO marked bottom-dead-center on the pulley).

Wed Feb 22, 2023 2:08 pm

I agree at 38 degrees it wouldn't start and even if it did it wouldn't run so sweetly. The timing light isn't adjustable. At first I thought light must be the problem so I bought a new one - also non adjustable. It reads exactly the same. I took the crank pully off and checked the gradations in relation to the woodruff key slot. They all look correct compared to other pulleys.

Wed Feb 22, 2023 2:46 pm

You never want to go over 32 at max RPM. Assume your timing light is fine. What happens to engine performance when you dial that advance down to 32 (at max RPM)? 32 before TDC is about 2 inches to the right of TDC. So scribe a little mark there if you need to.

Wed Feb 22, 2023 4:29 pm

Tom K. wrote: ...Assume your timing light is fine. What happens to engine performance when you dial that advance down to 32 (at max RPM)?...
Makes sense. Maybe it actually is at 38 degrees and starts and runs better that we expect. Maybe your static-timing was off by 30 degrees somehow?

You could slowly rotate the distributor so the timing indication reduces and see how the engine reacts. If it gets retarded too much, you'll know it. As you lower the timing, the idle speed will change, so you'll have to compensate by adjusting the carburetor.

Wed Feb 22, 2023 4:52 pm

Howdy ...

Are you DEAD CERTAIN the inductive pickup clamp thingy on timing light is around spark plug wire #1 ?

This has gotten me in the past ...

Just checking ... stay safe

jinx

Wed Feb 22, 2023 6:24 pm

Print this
https://www.thesamba.com/vw/archives/manuals/degree_wheel.php

Thu Feb 23, 2023 11:56 am

Check the distributor fly weights to see if one of your springs has broken or come off.

Fri Feb 24, 2023 4:26 pm

What distributor do you have?

Fri Feb 24, 2023 5:16 pm

Some questions from me...
Before you set the static timing... did you adjust the point gap/dwell?
If the dwell was way off it could cause the timing light to read something strange. Point gap with new points should be around 0.016". If using used points, dwell is more accurate. Set dwell to 45deg with used points. As the point cam follower wears the dwell# will increase.
Changes to dwell affect ignition timing. So re-adjust your static timing any time you adjust points.

Does your timing light have an "advance" function? This is usually a dial or digital setting in degrees. The number of degrees set is how many degrees delayed the light pulse comes. If your idle timing is 8BTDC and your timing light is set to 8deg the light will pulse when the TDC mark lines up with the case split. Instead of the light pulse coming 8deg BEFORE TDC it will come 8deg late just as the TDC mark lines up with the case split. This function allows you to adjust any amount of BTDC timing using just the TDC mark on the pulley. But it will not match the static timing.
I don't think this is your problem, but it is one reason why the static and strobe timings may be different.

If your inductive pickup is near the distributor cap... move it to the spark plug end of the #1 wire. Near the distributor cap there is much "noise" from the other spark plug wires. At the spark plug end the inductive signal is only coming from a single spark plug wire (#1).

Make sure you are connected to the correct spark plug wire (#1). Look at the engine tin near the spark plug. You should see the cylinder number embossed into the tin.

Sun Feb 26, 2023 2:20 pm

I just want to say thanks to everyone who has helped by replying to my question - what a great resource this is! I started the engine , took the revs up to 3000 and then gradually retarded the timing until I got it to read 31 degrees. The problem then was that it wouldn't idle very well. I sorted this by fiddling with the carb air screw. Now at idle the timing is reading 11 degrees. So I think I'm sorted. Thanks again all.

Mon Feb 27, 2023 3:58 pm

Is this with the 009? I can tell you how to make it run even better.

Mon Feb 27, 2023 4:07 pm

heimlich wrote: Is this with the 009? .

Seems to be...
fillpoke wrote: which I believe is right for a 009.

Mon Feb 27, 2023 4:25 pm

Glenn wrote: heimlich wrote: Is this with the 009? .

Seems to be...
fillpoke wrote: which I believe is right for a 009.

You're not helping when you're helping.

Mon Feb 27, 2023 4:35 pm

heimlich wrote: Glenn wrote: heimlich wrote: Is this with the 009? .

Seems to be...
fillpoke wrote: which I believe is right for a 009.

You're not helping when you're helping.
penetrating oil might loosen it up but it will lock up again. It's best to be taken apart, cleaned and properly lubricated.

But it would help of the OP would post some pictures,