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Tue Nov 03, 2015 8:53 am

Amskeptic wrote: "D" does not mean doghouse. It is the 1600 pulley for the 905mm belt.

If you have ^ ^^ spacing, it is 0/7.5/10

If you have a 5* ATDC *notch* you will have a "0" dimple on the outer pulley half. The dimple will, of course, line up with the crankcase seam before the notch as you rotate the engine.

Consult your every manual for the every permutation of timing marks that could very well somehow end up on your engine for reasons you will never know.
Colin

Tue Nov 03, 2015 10:21 am

Tcash wrote: Amskeptic wrote: "D" does not mean doghouse. It is the 1600 pulley for the 905mm belt.

If you have ^ ^^ spacing, it is 0/7.5/10

If you have a 5* ATDC *notch* you will have a "0" dimple on the outer pulley half. The dimple will, of course, line up with the crankcase seam before the notch as you rotate the engine.

Consult your every manual for the every permutation of timing marks that could very well somehow end up on your engine for reasons you will never know.
Colin
There are three listed stock pulleys with just a single notch and no TDC "dimple" markings....

'50-'65 1200-G1500 engine (single notch = 10BTDC)
some 1600cc Man&AT w/ DVDA (single notch = 5ATDC)
'76-later AT engines (single notch = TDC)(not certain if these have a TDC "dimple" in addition to the notch, but why would they need to?)

So if you only have a single notch, you would be wise to confirm what it indicates rather than assume it means 5ATDC or TDC. All you really need is to remove your pulley and use a right-angle square with one arm lined up with the center of the woodruff key slot and centered on the pulley hole. If the 90-deg arm lines up with your notch... the notch is TDC. If the notch is CCW from the arm it is 5ATDC. If the notch is CW from the arm you happen to have a 1200cc pulley and it is 10BTDC.

Fri Nov 20, 2015 7:20 am

keifernet wrote: Yep... dimple is TDC...

I have never seen a pulley with all the marks on it like in Glenns pic though... most of the time you either see the notch to the left of the dimple which is 5 ATDC ( orginally a DVDA distrubutor) or a single notch to the right which is 7.5 BTDC ( SVDA) VW did produce at least 5 pullies with different notches in them that I know of... maybe more.

Well, then how about this?

Engine code = D0986163

Fri Nov 20, 2015 8:57 am

kuseetha wrote: keifernet wrote: Yep... dimple is TDC...

I have never seen a pulley with all the marks on it like in Glenns pic though... most of the time you either see the notch to the left of the dimple which is 5 ATDC ( orginally a DVDA distrubutor) or a single notch to the right which is 7.5 BTDC ( SVDA) VW did produce at least 5 pullies with different notches in them that I know of... maybe more.

Well, then how about this?

Engine code = D0986163

Find top dead center on number one cylinder and see where those notches are at in relation to the split in the case. My bet is those notches are TPC.

Thu May 04, 2017 1:08 pm

I have a dimple and no notches, LOL.

79FISBCab

Thu May 04, 2017 8:37 pm

garyt wrote: I have a dimple and no notches, LOL.
One member just posted their crank pulley had no notches. When they held up a paper degree wheel they found the PO has welded the notches and sanded them perfectly smooth so you couldn't see them unless you were specifically looking for them.
Look carefully where the 5ATDC and 7BTDC notches "should be" and see if there is any sign of notches.

Also, some early degree pulleys had tape on or paint on numbers. Over the years you end up with an aluminum pulley with no markings at all. But this would not be a stock pulley and would likely not have a "dimple" at TDC.

Wed Jan 03, 2018 2:00 pm

This is what I'm looking at on my bug,
I think its a 1641 DP with a 009?
was thinking about checking the timing, but I think I will leave well enough alone until I know exactly what i'm doing.

I guess this mark if for timing and not TDC as a TDC mark is not really useful as checking the valves is just an approximate area so that all the valves on the particular cylinder that you are adjusting are open?

Wed Jan 03, 2018 2:17 pm

Unlimited Editions wrote: I think its a 1641 DP with a 009?
was thinking about checking the timing, but I think I will leave well enough alone until I know exactly what i'm doing.

I guess this mark if for timing and not TDC as a TDC mark is not really useful as checking the valves is just an approximate area so that all the valves on the particular cylinder that you are adjusting are open?

Go here https://www.thesamba.com/vw/archives/manuals/degree_wheel/VW%20Degree%20Wheel%20PDF.pdf , print out the diagram for pulley, find the TDC #1 dimple on the pulley, paint a mark the 30 BTDC on your pulley, use your timing light to time #1 at that at about 3500 rpm.

Would be OK to use a static light just to mark where your static timing fals before you start that, and OK to see where static mark falls after using the timing light to set.

Wed Jan 03, 2018 9:51 pm

Unlimited Editions wrote:

This is what I'm looking at on my bug,
I think its a 1641 DP with a 009?
was thinking about checking the timing, but I think I will leave well enough alone until I know exactly what i'm doing.

I guess this mark if for timing and not TDC as a TDC mark is not really useful as checking the valves is just an approximate area so that all the valves on the particular cylinder that you are adjusting are open?
I would actually suggest otherwise. A TDC mark is the minimum number of timing marks you need. It allows you to set valves and if you own a timing light with advance dial/settings you can set your timing to most BTDC values.

A timing light like this :

can adjust timing from TDC to 60BTDC using just a TDC mark on the pulley.
For a 009 distributor this is particularly useful. Because the recent aftermarket 009s are inconsistently built, you want to make sure they never exceed 32BTDC at ANY rpm. So you rev the engine and check that the timing stays below 32BTDC. Using a timing light like the one above, you would set the dial to 32deg and rev the engine. As long as TDC mark doesn't pass the case split you are fine. If you adjust the dial to the point where the TDC mark lines up with the case split you now know what the timing is by just reading the dial.
If you want to set the idle timing to 7.5BTDC, you set the dial to 7.5deg and rotate the distributor at idle until the TDC mark lines up with the case split.
So you see how a TDC mark can be more useful than an actual timing mark, as long as you have an advance timing light.

Thu Jan 04, 2018 9:35 am

Good response AshMan40 !!

I have a vintage timing light that doesn't have an advance, so I tend to forget that newer ones typically have that.

Thu Jan 04, 2018 2:27 pm

Thanks for the helpful straightforward advice!! i'll ad the strobe with the advance feature to my shopping list... haven't owned a ray gun for a while!!

It makes sense that is a TDC mark now as the dis is not pointing straight at no.1, this must be the advance? think I'm getting it! SLOWWWWLY.

Sat Jan 20, 2018 4:56 pm

My timing should be 5 ATDC according to my manual.

First, i have my timing light set at 0 degrees and the TDC dimple on the front of the pulley lines up with the split on my case correctly.

Second, I set my timing light to 5 degrees.

My question: Should the TDC dimple on the pulley line back up with the split on my case or should i line the v notch (5 ATDC) mark on the back of the pulley line up with the split on my case?

My timing should be 5 ATDC according to my manual.

Thanks for any help

Mon Apr 23, 2018 10:21 pm

Hi,

This is my pulley, AS engine, 1600dp. should I timing it on 5 ATDC which is dent? and marked behind is TDC? nor should I timing it at 7.5 btdc?

Tue Apr 24, 2018 5:30 am

kaupu714 wrote: My timing should be 5 ATDC according to my manual.
Ignition timing should be based on the distributor you have installed in the engine. In the decades since your car left the factory the distributor may have been replaced with a different model. Before we assume it still has the original distributor and should be timed at 5ATDC you should confirm the model# stamped into the body of the distributor. You may need a mirror since the numbers are typically on the front side of the body.

kaupu714 wrote: First, i have my timing light set at 0 degrees and the TDC dimple on the front of the pulley lines up with the split on my case correctly.
??? :? If your advance timing light is set to zero and the strobe is showing the TDC mark lined up with the case split at idle then your idle timing is TDC (zero deg). Zero on your timing light means it is not changing the strobe pulse and is flashing at the instant the spark pulse is detected thru the inductive pick-up..

kaupu714 wrote: Second, I set my timing light to 5 degrees.

My question: Should the TDC dimple on the pulley line back up with the split on my case or should i line the v notch (5 ATDC) mark on the back of the pulley line up with the split on my case?
With your timing light advance is set at 5deg, adjusting the distributor so the TDC mark lines up with case split will result in a timing of 5BTDC even though it visually appears to be timed at TDC.
The advance timing lights can be used to set any "BTDC" timing using just the TDC mark. As far as I know the advance setting on your timing light CANNOT be used for setting timing to ATDC values.

The function of the timing light advance DELAYS the strobe pulse. So a spark pulse that normally comes 7.5deg "BEFORE" TDC (7.5BTDC) can be delayed by the timing light to appear to come 7.5deg late when the TDC mark is just passing the case split. It cannot accurately strobe BEFORE the pulse is detected which is what you would need to have an ATDC timing pulse show up early.

Tue Apr 24, 2018 5:39 am

Amzoch wrote: This is my pulley, AS engine, 1600dp. should I timing it on 5 ATDC which is dent? and marked behind is TDC? nor should I timing it at 7.5 btdc?

The above timing notch appears to be the 7.5BTDC mark. Using the table above there were only two pulleys with a TDC dimple and a single notch. It is unlikely you have the 1950-1965 crank pulley which has the notch marking 10BTDC. That leaves the '74 crank pulley with a TDC dimple and a 7.5BTDC notch.

Whether you should set your timing to 5ATDC or use the 7.5BTDC notch on your crank depends on the model of the distributor you have installed. Look to the model# stamped into the metal body of the distributor and look up the # on this page to find the recommend timing.
http://www.oldvolkshome.com/ignition.htm
Backup site: http://fullmoonbusclub.com/forum/topic/144?page=1

Tue Apr 24, 2018 7:29 am

ashman40 wrote: The above timing notch appears to be the 7.5BTDC mark. That leaves the '74 crank pulley with a TDC dimple and a 7.5BTDC notch.

Looks like a TDC dimple and a 7.5BTDC notch to me.

I've used a paint pen to paint marks on my own pulley, you can see some of those here. "B" is bottom dead center (or TDC for #2 and #4), and 32 BTDC is for total advance. The TDC mark is not visible until the engine is rotated clockwise a little more.

Sat Jun 19, 2021 8:18 am

Bringing back this one from the dead because I came here looking for a printable degree wheel. Link is dead or gone, can we get this added to the first post some how?

https://www.hot-spark.com/Hot-Spark-009-VW-Type-I-Pulley-Degree-Template.pdf

Sat Jun 19, 2021 5:12 pm

That degree wheel only shows BTDC marks and references on the TDC mark so may not work well for adding ATDC timing marks. Also it may not help if you don't have a TDC mark to center on (not all pulleys have a TDC marking).
It can be helpful to note where 270BTDC (or 90deg ATDC) is as this is where the crank pulley woodruff keyway is located on all ACVW engines. This slot is at 9-o'clock on the ID of the crank pulley when TDC is straight up, as seen on the degree pulley below.

Using this keyway as your reference you can ID where TDC is located in case your pulley does not already have a TDC mark.

I made this paper template a few years back.

It has lines that extend to the center of the wheel. This way you can cutout the center and line up the 270deg line with the center of the woodruff keyway at the 9-o'clock position.
Print it out full size and it should be a 7-in diameter wheel.

Thu May 01, 2025 5:54 am

I know it's a old post, but, heck, it's a good place to start.

I am timing my 71 super, with a AE 1600 DP engine, currently statically timed at 5° ATDC as per just about every reference I have. It is running a single vacuum line distributor, I have no idea if it's stock or what. I have a aftermarket 34PICT carb. (my Solex is not happy right now, pse no haters)
I have a stock pully (I believe) with one notch, which I take to indicate 5° ATDC.

From idle, and "off from a start" I always seem to fight that little "bogging down" thing. Especially when the engine is cold. I have checked and set points (currently at 48° with the dwell meter), I have the idle set at 900 RPM, using the accepted method of setting idle, the accelerator pump seems to be working, and no evidence of a vacuum leak anywhere.

I am wondering if the distributor cam or whatever is a bit worn, and maybe I can advance the timing a few degrees and see if I correct the problem?
Thoughts please

Thu May 01, 2025 6:31 am

Chinaclipper wrote: I am timing my 71 super, with a AE 1600 DP engine, currently statically timed at 5° ATDC as per just about every reference I have. It is running a single vacuum line distributor
The 5° ATDC idle timing setting is strictly for use with fully functional DVDA type distributors, which is what your 1971 Super originally came with, and hence what your references' information is pertinent & applicable to.

However, if you are running a 34 PICT-3 style carb with a SVDA distributor setup (which is what it sounds like you are describing above - "single vacuum line distributor"), then you want to be using approximately 7.5° BTDC for your idle timing setting.

Trying to get a smooth idle and good performance with your current carb + distributor combo and using a 5° ATDC timing setting is nearly impossible. I.e., that's running it at about 12 to 13+ degrees retarded from where it's supposed to be, and thus makes for a huge degradation in acceleration performance, along with upper RPM fuel economy & power!!