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Thu Jul 28, 2011 7:06 pm

I have a '72. This week I ordered a new distributor from KGPR. Today I received a Richporter distributor.

I have reviewed the Bentley manual carefully on installing a new distributor. Before I removed the old distributor, I made sure the engine/rotor was in position to fire plug #1. The rotor was pointing the hash mark located at approximately 5 o'clock on the old distributor (and on the crankcase).

Here's my problem: The new distributor has no hash mark so I don't know where #1 is. If I leave the crankshaft pulley in the same position it was when I removed the old distributor and then drop in the new one, the rotor is at around 2 o'clock.

Is there a way to install the new distributor correctly? Thanks.

Thu Jul 28, 2011 8:11 pm

As long as you haven't turned the motor just install the new distributor - the drive dogs are offset so there is no danger of getting anything out of time. Not that you won't have to reset timing - you will. Turn the rotor as you push the distributor into the case. It'll only fit one way - and it will pop into place - you'll know when you get there. After the dist is locked into the dist drive you won't be able to turn the rotor without rotating the motor - not that you could by using the rotor. Look at where the rotor is pointing. The nearest post on the cap will be #1. Going clockwise next is 4 - then 3 then 2. Time the engine and you're done. It's that easy.

Fri Jul 29, 2011 2:52 am

Thank you!

Fri Jul 29, 2011 5:19 am

In addition, I'd double check the timing curve on your new one to make sure it's what you want. My Pertronix was WAY off where it should have been and ran terrible, I had to make considerable changes to get the curve where I wanted it. You didn't say whether you have a mechanical or dual advance, but most guys time mechanicals at 30-32 degrees total measured at full advance (3000+rpm).

Good Luck!

Fri Jul 29, 2011 6:32 am

That sounds like good advice. How do I check this?

Fri Jul 29, 2011 7:07 am

1. Verify TDC with a piston stop tool.

2. Mark your pulley for 30° or whatever you want for max timing.

3. Set your timing using a timing light at 3000+RPM.

4. See where your base timing falls and if the timing curve meets your desires.

Here's an article I wrote for my local club newsletter:

Timing is everything. Is my car really in time? (Part 1)
Making sure the ignition timing is correct in your VW is critical for an air cooled engine. Because of
the much hotter component temperatures, air cooled engines are much less forgiving about over advanced
ignition timing than water cooled engines. Even a few extra degrees of timing advance can spell death in
the way of a burned piston, burned or dropped valve, cracked head or other terminal failure. Everything
related to the ignition timing has to do with the accuracy of the timing marks themselves on the crank
pulley. Being that many of our engines have unknown histories and were assembled from different parts
piles, locating exact TDC is a wise move to protect your engine from an early demise. Locating exact TDC
is a simple process which only took me about 10 minutes including making the tool, let me explain the
process.
1. Take an old spark plug and grind the top chamfer from it that retains the porcelain insulator.
2. Grind or cut the ground electrode off.
3. Using a hammer and punch, knock the porcelain out of the steel shell from the bottom.
4. Run a 3/8" NC tap through the empty spark plug shell.
5. Snug a 3/8" x 3" long bolt into the shell.
6. Remove #1 spark plug with the piston halfway down and snug your new tool into the #1 spark plug hole.
7. GENTLY rotate the engine by hand until the piston stops against the tool.
8. Make a pen/pencil mark on the pulley at the engine case parting line, and be exact. Tip: Use white
masking tape on the pulley and a sharp pencil to make your marks.
9. Rotate the engine in the opposite direction until the piston again touches the tool.
10. Make another mark with a pencil at the case parting line.
11. Measure the distance between the two marks with a flexible tape measure and divide in half. Find the
exact halfway point between the two marks, this is your EXACT TDC. Mark this with the pencil.
12. If your pulley has a TDC mark from the factory, verify that it agrees exactly with your halfway mark.
13. If you have no TDC mark from the factory, use the sharp edge of a metal file and notch the edge of
your pulley firmly.
14. Take a toothpick with a dab of white paint on it, and fill in the notch in the pulley to make it more visible.
15. REMOVE THE TOOL and reinstall the spark plug!
Now that you have TDC identified correctly, you might want to check your total advance. This is easy if
you have a high-buck Snap-On or Mac timing light that has advance built into it, but let’s cover the basics
for those who have a standard strobe-style timing light. VW only has you check your initial timing at idle,
and not total advance. Total advance is the important number, though. VWs seem to have more
catastrophic failures when total advance exceeds 30-32° BTDC measured at 3000RPM or more, this is to
verify your mechanical advance is working correctly and total timing is not too excessive. The next
problem is, where the heck is 30°? Well, we can find that accurately using some basic mathematics.
Using a wide flexible cloth tape measure, find the circumference of your crank pulley after removing the Vbelt.
Most measure about 21-22”. You can take this measurement, divide by 360 (number of degrees in a
circle) and multiply by 30 to find the distance from TDC to 30° BTDC, or you can eliminate one step and
just divide by 12 to find your total timing position. Let’s take an example:
Mike Roecker’s ’66 Beetle 1300 has a pulley that measures almost exactly 21” in circumference.
21” circumference ÷360= .058333” for one degree, or:
21” ÷12=1.75” which is 30° from TDC.
So, it’s relatively simple on Mike’s car- we identified TDC using the procedure above, and measured 1.75”
to the right of TDC from the TDC mark to find where his total timing should be. Once again, I used the
edge of a file and notched the pulley, and a spec of white paint to lighten it up. Interestingly enough, the
’66 1300 does not have a TDC notch from the factory, only 7.5° and 10° BTDC notches on the pulley.
Another interesting note is that Mike’s 1300 has no centrifugal advance, relying totally on vacuum for all of
the timing advance. I was surprised to find by testing his car that it did reach 32° total timing with the
vacuum advance hooked up, and total advance was reached at only 4”Hg of vacuum! I think his car has
the best low end torque of any Beetle I have ever driven, that carb/distributor combination is “spot on”. I’ll
continue this article next month discussing different types of advances and testing them. For now, keep on
driving those classic VW’s!
_____________________________________________________________________________________
_____________________________________________________________________________________
Timing is everything. Is my car really in time? (Part 2)
In part 1 of this series I discussed finding exact TDC and how important this is in verifying that the ignition
timing on your VW is correct. I’ll now expand on different types of distributor advances and how to test
them. On my 2180 I have a mechanical advance only distributor, determined my TDC, and marked my
pulley as stated before. I’m using 30° as my target for total advance so I am not concerned about initial
timing, only total timing at maximum advance. I set my timing at 30° at 3000RPM, making sure all of my
mechanical advance is “in” by that RPM. This is done by attaching the timing light, revving the engine with
the light on, and watching the marks move. If the centrifugal (mechanical) advance is working correctly,
the timing marks will move about 20° in my case. The general theory is to verify your centrifugal advance is
“all in”, set your timing at an RPM above that level, and let the initial setting fall where it may. In my case, I
have about 20° total centrifugal advance and 10° initial for my total of about 30°. It’s a good idea to check
this periodically to verify your advances are working correctly and you have the correct total advance.
Verifying that your timing scatter is not excessive is also a good idea, in a perfect world there would be no
timing scatter but most cars I work on have a couple of degrees. Spark scatter is how much the mark
“moves around” while you’re looking at it with a strobe timing light. If it’s excessive, like 5 or more degrees,
it’s time to find out why. The distributor could be at fault, or worn/loose drive gears in the case. I have a
Chinese manufactured 009 that has at least 5 degrees of spark scatter, I wonder what it would bring on
Ebay? ☺
I have experimented with several distributors on my 2180, all junk, just stockers and cheapie 009s that I
had laying around. I ordered a new Pertronix cast distributor (PN D186604) because I wanted electronic
ignition and a small style housing. The factory curve on the Pertronix cast was terrible- it had way too much
advance starting at way too high of an RPM and ran very poorly. Out of the box it was about 30 degrees
total advance starting at 2500RPM and “all in” by 3500 rpm. With 30 degrees centrifugal advance and my
total timing set at 30° with the centrifugal “all in”, my base timing ended up at TDC. This was the WORST
curve I have ever driven in a car because it basically ran at TDC until 2500rpm! Once I recurved the unit I
was able to bring total advance down to 20° which puts my initial at 10° BTDC, and reduce the RPM where
it completed advance to about 2500. It’s a nice curve and it runs great! If you’re not happy with the
performance of your engine, take a hard look at the advance curve- it should be similar to what I have.
Most distributors are adjustable inside if you have a little ingenuity. On mine, I reduced the total advance
by sleeving the limit stop pin with a small piece of brass tubing purchased at the local hobby shop. I also
installed a lighter spring to get the advance to start earlier. Yes, many distributors only have one advance
spring installed from the factory with the “hooks” for the second spring not used.
Vacuum advance is another issue. Many stock VW’s run two types of advance- both centrifugal and
vacuum. The idea here is that the centrifugal will give the correct timing for the RPM, and the vacuum can
give you a bit more advance under light load conditions. During light load (part throttle cruise), the
volumetric efficiency of the engine is down due to the throttle plate being mostly closed. Volumetric
efficiency is quickly explained by how well the cylinder is filled with the air/fuel mixture at the bottom of
each intake cycle. On a naturally aspirated engine it may run 70-90%, on a turbo or supercharged engine
it will run well over 100% under boost. With cylinder filling (volumetric efficiency) lowered during part
throttle cruise conditions, more timing advance can be dialed in without fear of engine damage. This
increased advance (within limits) will result in better fuel economy, lower engine temps, and better throttle
response. As soon as the driver opens the throttle, the vacuum goes away and the timing returns to the
mechanically advanced baseline so that it is not too far advanced. This is why SVDA (singe vacuum dual
advance) distributors are suggested for most street applications and centrifugal advance distributors are
suggested for most race applications. There are also DVDA (dual vacuum dual advance) distributors that
use both intake manifold vacuum and ported (venturi vacuum) to control the timing advance. These are
seen mostly on later engines subject to emission control regulations.
The difference between intake manifold vacuum and ported (AKA venturi) vacuum is that intake vacuum is
tapped below the throttle plate and strongest at an idle, lowering as the throttle is opened. Ported (venturi)
vacuum is tapped off of the side of the carburetor just above the throttle plate. It measures zero at idle and
is strongest at a part throttle setting, dropping considerably at wide open throttle. Venturi vacuum is
preferred for most timing advances in a street driven vehicle.
How often should you check your timing? In a perfect world you should only have to set it once and never
check it again, but this is far from a perfect world. I check mine a few times a year, just to make sure
nothing has moved. Remember the consequences of incorrect timing can be terminal, and it only takes a
minute to check it and make sure the advance(s) is working correctly. Many of us are running distributors
that are several decades old and I have found there is a high failure rate among both mechanical advances
and vacuum advances in these old components. How do I verify my vacuum advance can is not
defective? If you have a hand held vacuum pump, it is quite easy to connect this to your advance
diaphragm and give it a couple of pumps. The vacuum gauge on your pump should rise up and remain
steady, and the point plate or advance plate should move roughly a quarter inch. If it will not hold a
vacuum, the diaphragm is perforated or rotted from gasoline fumes. Most advance diaphragms are rubber,
not neoprene, and subject to rot from gas fumes when the car is parked. If you don’t have a hand-held
vacuum pump, you can use your mouth to create a vacuum on the end of a vacuum hose attached to the
advance can. You should be able to pull a vacuum, block the hose with your tongue, and have it hold a
vacuum. Yech, I know! At the same time you should watch the advance plate move inside the distributor
advancing the timing. You may not know how many inches of mercury you’re pulling, but at least you know
the diaphragm is not shot and the advance plate is not frozen. Why does the tube that is part of my
vacuum hose have that funny little upward swoop in it? This is to prevent the gasoline fumes from
migrating down into the vacuum advance can and rotting the advance diaphragm when the engine is off.
Another item that needs occasional maintenance is the felt pad under the distributor rotor. It needs a drop
of oil on occasion to lube the upper bushing in the distributor. I’ll also comment about the o-ring that seals
the distributor housing to the engine case. Most parts suppliers will give you a regular round o-ring with fits
terribly and requires excessive force to install the distributor. Seek out a “D” cross section sealing ring
which will allow the housing to be installed much easier. VW discontinued the OEM ones (PN 111-905-
261) so we must seek out the correct style from aftermarket sources.
Have fun, and keep on driving those classic VW’s!

Fri Jul 29, 2011 5:11 pm

I don't think I have done this correctly. The car won't fire without backfiring.

Here are the steps I have taken thus far:

1. Before removing the old distributor, #1 was at the hash mark on the distributor, or about 5 o'clock.

2. I dropped in the new distributor without turning the engine. When at #1, the rotor points to about 8 o'clock.

3. Assuming the distributor post at the 8 o'clock position was #1, I installed plug wires clockwise, 1 4 3 2.

4. I assumed 3 and 1 were left and right plugs at the front of engine, with 4 and 2 left and right at the rear.

I thought I'd done everything right but apparently not. Any comments would be much appreciated!

Fri Jul 29, 2011 5:25 pm

I'm not quite following what you're saying, so let's start over. The ONLY thing that matters is the relationship between the rotor and the tower on the distributor cap. What you should have done is rotate the pulley until the rotor pointed exactly at a cylinder (people like to use #1, although any one works as long as you know which one it is). Remove the distributor. Drop your new unit in, making sure the rotor points to the same tower on the cap.

(Fussy people like me do a static time of the engine next, putting the pulley where I want the timing and rotating the DIST counter-clockwise until the points open and the coil sparks.)

If you're really lost, can you get back to where it will run with the old dist and use my method?

Fri Jul 29, 2011 6:09 pm

OK, thanks. I think this is start to sink in. I appreciate your time.

Fri Jul 29, 2011 6:20 pm

If you have a OEM pulley or a quality aftermarket one like a Berg or CE then there's no need to verify the TDC mark is correct. If you want and easy way, just remove the crank pulley bolt and the woodruff keyway should be 90° to the left or at 9 o'clock.

Then you need to see if you are at TDC on #1 or #3. Just remove the left valve cover and have someone rock the crank a few inches left and right. Watch the #3 rockers, if BOTH move then you are on overlap and at TDC on #1. If only one moves then rotate the engine 360° and line up the TDC mark. You are now at TDC on #1.

No need to stick things into the spark plug hole.

Most modern timing light have a feature where you can "dial in" the advance, so only the TDC mark is needed. Set the tight to say 30° and it will retard the light so it illuminates the TDC mark when the ignition is at the set advance.

Fri Jul 29, 2011 7:31 pm

Glenn:

You are a smart man and I respect you, but I don't agree with you. Not all VW pulleys have a TDC on them, some only have timing marks. Being that most of our engines have less than virgin backgrounds, I feel it is important to verify TDC on any aircooled VW. Also, I've seen several high dollar Snappy and Mac timing lights with advance built into them that was off by a country mile- if you dialed in 30 you got 20 or 40.

My feelings are keep it simple, verify your TDC and use a regular timing light at 3K (or whenever it's "all in".)

Respectfully,

Fri Jul 29, 2011 7:34 pm

Bruce.. no problem.

I've been using a Berg pulley for the past 30 years and my OTC timing light is dead on. I tested it on my calibrated Sun Distributor Tester.

I guess you can't be too safe, but i've never had a problem with stock pulleys.

Mon Sep 07, 2015 2:36 pm

I just installed a Richporter VW10 distributor on my 71 Ghia.

The Richporter didn't come with technical information, wiring diagrams, etc., so there is some good judgement that had to come into play.

I ran into the same issue that the first poster did with no well marked number 1 cylinder index on the distributor body. What I ended up doing (I had the #1 Cylinder at TDC), was to get the rotor in the right place for #1, rotate the body of the distributor so that I knew that the cap (and #1 wire) would line up with the rotor at the #1 position. Once I had that solved, it was pretty easy to transfer the wires in the correct firing order (1-4-3-2).

I downloaded a template off of the Hot Spark website that was a full size paper template of the Type 1 pulley and I used a silver sharpie to mark TDC, 7.5 BTDC and 32 BTDC.

I noticed that timing was a little tricky since I couldn't get 32 degrees BTDC at 3000 rpm and 7.5 BTDC to both come in. I had read that you always want the 32 degrees BTDC to be the setting to try to achieve. I set the timing based on that (vacuum line plugged).

It is a huge improvement over the 009 Distributor I was previously running. Engine seems to be much smoother and no dreaded dead spot.

Mon Sep 07, 2015 6:01 pm

It can be tricky with the mechancial advance side to get 32 degrees maximum advance and the as advertized static timing to both line up on hte same distriubotr. The important one is the maximum advance not to exceed 32 degrees. Let the idle fall where it will. As long a its not crazy like 15 degrees or more let it be.