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Sat Sep 12, 2020 1:05 pm

I’m having trouble with the engine running good. Sounds like it’s running on 3 cylinders. All new plugs & wires, distributor. Adjusting the carburetor does not provide much for me.
My timing wheel has only one notch in the front only.
I’m going by the white one in front. At idle where should it be?
It is to the right & moves to the left at higher RPM.
Thanks for any help!

Sat Sep 12, 2020 1:37 pm

First off: what carburetor and what distributor are you running?

Let's establish that front/forward is the front/driver end of the VW.

It seems to me that the forward rim of the crankshaft pulley has the notch at the 5 degree after TDC mark (5 ATDC). That 5 ATDC would be the correct ignition timing mark for a 1973 with stock carburetor and stock distributor.

And the rear rim of the crankshaft pulley has the "dimple" to the right of that at the TDC mark. I don't know who made or why there's a white paint mark on the rear rim of the crankshaft pulley.

We're ignoring the rearmost small AC pulley for all this.

Sat Sep 12, 2020 2:00 pm

Agree with Cusser. For now, ignore the white mark on the rear facing (rear of car) lip of the crank pulley.
The notch is 5ATDC and the proper idle timing mark when using a DVDA distributor with a functional vacuum retard system. The working vacuum retard system removes 8-12deg of timing advance at idle taking the idle timing down to 5ATDC.

Look up your distributor model number here to find out how it should be timed. If you are running a non-original distributor in place of your '73 distributor you need to adjust ignition timing based on the distributor you have installed, not your factory timing.

Sat Sep 12, 2020 3:11 pm

Electronic ignition. So should the timing be set right on the crack on the engine?
Yes ignore the ac pulley and the denote.

Sat Sep 12, 2020 3:39 pm

Cusser wrote: First off: what carburetor and what distributor are you running?
If nothing has changed from this earlier pic in the OP's gallery, looks like we're dealing with an 009 and H30/31 combo.

Sat Sep 12, 2020 3:46 pm

mukluk wrote: Cusser wrote: First off: what carburetor and what distributor are you running?
If nothing has changed from this earlier pic in the OP's gallery, looks like we're dealing with an 009 and H30/31 combo.

If that's the situation, I'd static time at 7.5 BTDC (before top dead center, and you don't have a mark for that on your pulley) and maybe set totl advance at 3500 rpm to about 30 BTDC with a timing light.

Sat Sep 12, 2020 5:58 pm

Yes it is the same, 30 31 & same distributor. No vacuum advance. Thanks!

Sat Sep 12, 2020 7:44 pm

glennj3cub wrote: Electronic ignition. So should the timing be set right on the crack on the engine?
The case split is where the marks on the crank pulley are lined up under the strobe timing light when adjusting timing.

Electronic ignition module does not change the timing they just make the trigger mechanism more accurate and can improve the dwell time. The recommended timing is based on the ignition timing curve which is controlled by the weights+springs of the mechanical advance (and vacuum advance/retard where applicable). They control how much and when the timing changes.
Note that some electronic modules will change the rotation of the distributor body because they change where in the rotation the sparks are triggered. This can change where the #1 spark plug wire is located on the cap.

glennj3cub wrote:
Yes it is the same, 30 31 & same distributor
Since you are not running the stock distributor you should not use the stock timing marks. Add marks or notches for 7.5BTDC, 28BTDC and 32BTDC.
Agree with Cusser to start with idle timing of 7.5BTDC. If you were using the single 5ATDC notch previously this will advance your timing 12.5deg. That is a ton of extra advance which will mean more power at idle. If you were previously using the white mark on the rear lip of the crank it will be even more!
Once you get the engine running and warmed up, follow these steps to get that 009 timed correctly. You really need to make sure at total advance the distributor never produces more than 28-32BTDC of timing. More than 32BTDC and you will risk detonation at higher rpms under load.

Sun Sep 13, 2020 6:51 pm

Thanks again. I’ll measure and make the correct marks tomorrow then set the timing. I don’t have a tach so I’ll look for one.

Sun Sep 13, 2020 6:58 pm

You really don't need a tach to set timing at high rpms. Watch the timing marks under the strobe light as you raise the rpms there will be a point where you can increase the rpms but the timing no longer increases. This is max timing. You never want this to exceed 32BTDC with rpms-based mechanical advance. Find the sweet spot between 28-32BTDC where it runs best.
Once you determine your max timing is at 32BTDC, let the rpms drop to idle and use this as your max reference. If your idle timing is above this spot you know your max timing will be above 32BTDC.

Sun Sep 13, 2020 9:05 pm

I normally just listen to guess the RPM (900).
So I know realize I was setting the timing wrong anyway. I thought 7.5 degrees BTDC would be 11.5 mm to the right of the crankcase split. From what read the 7.5 mm Mark should be on the split at idle! That will change things a lot!

Mon Sep 14, 2020 5:27 am

glennj3cub wrote: I thought 7.5 degrees BTDC would be 11.5 mm to the right of the crankcase split. From what read the 7.5 mm Mark should be on the split at idle! That will change things a lot!
The timing marks on the ACVW are the opposite of what many other car makers use for timing marks. Instead of a stationary index and a TDC mark on the rotating part (pulley, flywheel harmonic balancer)... VW used a stationary pointer (case split) and the index is part of the rotating crank pulley. This aftermarket degree pulley illustrates this well:

This also means the timing marks move differently as the timing advances. If the timing were at TDC the "TDC" mark (dimple on your pulley) lines up with the case split. As the timing is advanced so it fires a spark BEFORE the piston reaches TDC the CW rotating TDC mark on the crank pulley will not yet have reached the case split. This means a point CW from the TDC mark on the pulley will be lined up indicating BTDC timing.
Your existing 5ATDC notch is CCW from the TDC dimple indicating it is an (A)fter TDC mark. For it to line up with the case split the spark will come AFTER the TDC mark has passed the case split.

Hopefully this change allows your engine to run well.

Mon Sep 14, 2020 8:14 am

Lots of information for my brain to take in. I need to keep it simple 😊.
Please clarify for me. I use the crank case split. Measure the flywheel distance for 7.5 & 30 and time with a light, putting the 7.5 on the split at idle. I can go from there.
I appreciate your efforts!

Mon Sep 14, 2020 10:32 am

Yes.
Make new makings (or notches) on your crank pulley (not flywheel) for 7.5BTDC and 30BTDC.
7.5BTDC is CW from TDC but 1.5x the distance the 5ATDC notch is CCW from TDC.
[5ATDC notch] <-- 5deg --> [TDC "dimple"] <--- 5deg length x 1.5 ---> [7.5BTDC mark]

For the 30BTDC mark, you will need to break out your high school geometry. The crank pulley has an OD of about 7-inches. Pi x 7in = 21.99in. Break this into 360deg slices (21.99 / 360) and you get 0.061" per degree. You want 30deg BTDC (0.061 * 30deg) and you get 1.83-inches CW from the center of the TDC "dimple".

You can static time your distributor to the 7.5BTDC mark. This will be good enough to get it running. Once it is running, use the steps above for timing a OO9 to make sure it does not exceed 32BTDC. The reason you need to do this is because of the lack of quality in most OO9s. When Bosch still made them in Germany, you could reliably set timing at idle and not worry about over advancing at high rpms. But since OO9s have been made by many different manufactures worldwide, the quality is all over the place.

Mon Sep 14, 2020 11:50 am

These are the timing marks (not running) but where they are when running. Does this look OK? The high RPM just barely got there.
But I noticed I could turn the mixture needle all the way in & it kept running!

Mon Sep 14, 2020 10:34 pm

glennj3cub wrote: These are the timing marks (not running) but where they are when running. Does this look OK?

Maybe its just my eyes by the new white mark just CW from the TDC dimple looks closer to TDC than the 5ATDC notch is. This would mean it is less than 5BTDC. Were you trying to make a mark at 7.5BTDC? Also, your timing marks need to be more precise. The new white mark appears to be about 3deg wide. I recommend a thin black permanent marker or pencil line in the white paint to clearly locate the timing mark.
While you are at it, you should mark the TDC “dimple” in white paint. Again add a thin line that splits the TDC dimple so you know exactly where TDC is.

glennj3cub wrote: The high RPM just barely got there. But I noticed I could turn the mixture needle all the way in & it kept running!
Even if you had the timing off by a few degrees the engine should have easily revved to 3000+ rpm. Is there some other issue with the engine? I’m assuming you saw the timing marks move as the rpms increased? That confirms the distributor is advancing the timing. Did you set the point gap/dwell? That needs to be done before you adjust the timing since dwell changes affect timing.

Tue Sep 15, 2020 9:04 am

I have to say I’m confused as Hell now. It’s electronic ignition so a dwell is not used. That’s for setting points?

The TDC notch in the pulley is 5 degrees when set on the crank case split.
The 2nd painted spot is supposed to be 7.5 degrees. I measured 11.5 mm from the notch on the pulley. At idle I have the 7.5 degree on the split.

The 3rd notch I measured 46 mm from the v notch to mark the 30 degree BTDC

I put the marks on so I know which area if the mark is most precise.
The engine revs up good and yes the mark moves at higher RPM.

I want to get her right and obviously need help.
Thanks!

Tue Sep 15, 2020 9:08 am

I notice in a picture up top of the nice clean pulley showing TDC & 7.5 degrees. I see the notch is not on the split but is in the left side of that protrusion on the split. Where are we talking that the split is actually located?

Tue Sep 15, 2020 10:10 am

Mark 30 BTDC on your pulley, print this out https://www.thesamba.com/vw/archives/manuals/degree_wheel.php

Rev engine to what feels like full throttle like 3500 rpm with timing strobe set up on #1 wire, rotate the distributor to align the split with the new 30 BTDC mark. And don't worry about where the mark is at idle.

Tue Sep 15, 2020 10:10 am

I previously tried to do a static timing. The light stays on all the time. Light is to the neg. coil & the other end is grounded. Turning the distributor will not turn off the light.