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LexTR3
05-23-2012, 11:19 AM
I know this is rather basic, but could someone describe how to set up the test light to set static timing?

martx-5
05-23-2012, 12:05 PM
You can use a a 12V test light, or a DC voltmeter. Bring the engine up to TDC by aligning the pointer with the hole in the pulley. It doesn't matter if your on #1 or #4 cylinder. Turn the knurled nut on the distributor and find the long hash mark and line it up with the marker. This will put the adjuster in the middle, and will always give you a reference point. Loosen the distributor pinch bolt. Attach the test light or voltmeter to the coil. Do this on the side where the wire goes to the distributor. If using a voltmeter set it at DC volts, and clip the red (+) lead from the voltmeter there. Hook the other end to the negative on the battery. This goes for the test light or the voltmeter.

Turn the ignition on, but DO NOT CRANK THE CAR OVER, or you'll have to start over again.

If the test light is on, or the voltmeter registers, turn the whole distributor CCW, until the light goes off. Then turn it back until it just lights. Tighten the distributor pinch bolt.

If the test light is off when you turn on the ignition, turn the distributor CW just until the light goes on or the meter registers. Tighten the distributor pinch bolt. Now you can advance the timing with the knurled nut. Each mark is equal to 4 crank advance (2 distributor advance), so start with the basic factory setting of 4 (one hash mark). Then you can play around from there using the knurled nut and always know where you started from.

LexTR3
05-23-2012, 12:33 PM
Thanks, Art.

dklawson
05-23-2012, 12:33 PM
Rather than repeat it all here, you can look over the PDF linked below.
https://home.mindspring.com/~purlawson/files/StaticTiming.pdf

TFB
05-23-2012, 01:05 PM
If you had a helper,your ammeter can also work as your indicator(although probably not worth the bother since the dist. is esay to view and just looking at points should be close enough.)At least thats what I do on my old cycle.points closed indicates slight discharge that ticks back to zero as I rotate distributor and they open.
Tom

TR4A_IRS
05-23-2012, 01:44 PM
On a related note, I set my timing using a test light a few weekends ago. I have a pertronix installed in my distributor, but I believe the process is very similar to if I still had points.

While rotating the distributor, my test light went from dim to bright (some folks say it goes from off to on, but that has never been my experience) and that was my indicator that I had properly set my timing.

What I didn't expect, was that I also received a shock when my test light got bright. Have any of you esxperienced that before. I know it was a shock, because I went through the process three times, just to be sure. In retrospect, that was probably a bad way to verify what was happening, as I could have hurt myself, or my ignition, but what is done is done.

dklawson
05-23-2012, 01:51 PM
You will get a shock from the low-tension side when the points open. That is normal. That energy is typically absorbed by the condenser... you just became part of the circuit.

LexTR3
05-23-2012, 02:20 PM
Doug: Many thanks for the link. Very helpful.

poolboy
05-23-2012, 03:02 PM
Any ol' VW guys around ?
Remember John Muir's classic publication ?

dklawson
05-23-2012, 03:41 PM
Do you mean "How to Keep Your Volkswagen Alive"?

I still have a copy in the garage. It's a great book full of "how tos" when you don't have the factory tools.

Geo Hahn
05-23-2012, 04:38 PM
Just for fun I use a 12V buzzer instead of the light. Lets me focus my old eyes on the crank when checking timing vs keeping one eye on the light.

If you connect the light between the battery and the low tension lead you can leave the ignition off and also avoid any shock.

Yes, John Muir. Good stuff -- at least we don't have to debate or remember which end of the engine is front ("front is front").

poolboy
05-23-2012, 05:36 PM
Do you mean "How to Keep Your Volkswagen Alive"?

I still have a copy in the garage. It's a great book full of "how tos" when you don't have the factory tools.

How about the subtitle..got to love it
"A Manual of Step by Step Procedures for the Compleat Idiot".
And tools..you right. At the time except for a floor jack I had all the tools needed to rebuild the engine in an Ammo can.

BTW if anyone who is not familar with the book and is wondering why John Muir worked his way into this topic it's because of his compleat disregard for a strobe light.

TR3driver
05-23-2012, 06:12 PM
Ah, I knew I'd heard that name somewhere, but couldn't place it. There's a copy of "Keep your VW alive" on my bookshelf, although as it turned out I only had a bug in my possession for about 4 days.

Could've had more when a friend cleaned out his garage, but I didn't have any place to keep them either.

TR4A_IRS
05-23-2012, 10:44 PM
Thanks Doug. I don't feel like a compleat idiot anymore!

af3683
05-26-2012, 02:41 PM
I just followed very carefully the above instructions to set the static timing on my TR3B. The car will start but is running very rough. Can anyone describe the proper orientation of the vacuum advance unit. Mine is sort of pointing down and left toward head light. I did tighten the bolt just as the test light went on. Any help would be appreciated. Thanks.

Art

Geo Hahn
05-26-2012, 03:10 PM
...Can anyone describe the proper orientation of the vacuum advance unit...

I don't think you can judge the reasonableness of a distributor setting by looking at the orientation of the the vacuum unit as that unit (and the whole distributor) may have been inserted into the cam shaft gear in a position that is off by a tooth or more. Can still be timed okay like that but the with a different vacuum unit position other than what the factory had in mind(which was roughly parallel to the block).

Any timing setting done in the garage is subject to tweaking along the road as you drive. But rough running could be attributed to other factors to.

Typical distributor orientation...

https://i1214.photobucket.com/albums/cc499/Ahwahnee18/TR3/DistributorOrientation.jpg

If the idle is rough you can certainly adjust the distributor a bit based on that -- turning until you get maximum idle ROM than backing off a bit.

My usual sequence is: valve adjustment, points gap, timing, carb sync, mixture adjustment then get on the road for final adjustment of timing & mixture.

af3683
05-26-2012, 03:56 PM
Thanks George. The car was running decent before I "adjusted" the timing. My goal was try to see if I could get it to run even better and learn how to set the static timing. The orientation of the vacuum advance was similar to yours before I started. It seems like I have the hole and the marker lined up and I'm turning the distributor CCW until the light goes out and then CW just until the light goes on. It seems so simply. I probably should have left well enough alone.

Art

af3683
05-26-2012, 04:40 PM
When I did the static timing I connected one end of the test light to the connector on the distributor where the wire goes to the coil, and the other end of the test light to the positive battery terminal (ground). I assume that the wire from the coil to distributor is <span style="font-weight: bold">not</span> supposed to be disconnected at the distributor when you do this.

Art

TR3driver
05-26-2012, 05:52 PM
There are several different ways to do it; any one will work as long as it indicates when the points open (which is when the spark happens). With your method, Art, you would need the wire connected, and the ignition switch on. Then the light would come on (indicating the points just opened) as you rotate the distributor clockwise.

af3683
05-26-2012, 06:16 PM
Randall, I was reading the Ken Gillanders method and his method is to remove the low tension lead and to connect the light to the distributor terminal and a hot lead (negative side of the battery). Ken does not say to turn the ignition on. He then turns the distributor CCW until the light just comes on and then CW until it just goes out. John Twist's Youtube video seems to imply the same. I guess I'm wondering it I use the Gillanders/Twist method will that give me a different result, make the engine run smoother, and possibly change the orientation of my vacuum advance back closer to parallel with the block? Im confused. Thanks.

Art

af3683
05-26-2012, 06:47 PM
I just went and looked at my car. I have the hole on the pully and the pointer lined up as best I can, but noticed that the points rubbing block is a bit to the right of the corner of the square lobe. It is not right on the corner. Does that mean that the timing marks are not perfectly lined up? Could that be my problem?

Art

Geo Hahn
05-26-2012, 07:01 PM
Sounds like I use Ken's method (light connected to disconnected low tension lead &amp; battery - ignition off) but there are many ways to do this.

A couple of thoughts...

We all tend to assume that the timing marks are correct but it is pretty easy for them to be off (by a little or a lot) depending on the care taken when the front pulley was last mounted to the engine. A mark that's off a bit will give you an innacurate starting point but if the engine runs then it is at least good enough to finish te job 'by ear' or 'seat of the pants'.

The approach you describe -- "I have the hole and the marker lined up and I'm turning the distributor CCW until the light goes out and then CW just until the light goes on" sounds like it will set the timing at TDC so you should be backing that off to about 4 BTDC to get to your starting point (one way is to use the vernier knob on the distributor).

When you move the engine to TDC, i.e. get the hole &amp; the pointer lined up) it is best to do this with the engine rotating in its normal direction (CW as viewed from the front). If you go too far then back it up aways and try again approaching once more from the normal direction of rotation. The reason for this is the likely slack in the timing chain that introduces some slop between the movement of the crank (pulley) and the camshaft (distributor).

At this point (engine will run) I'd be tempted to dial it in better by ear, road test it for any pinging (and adjust if need be) then see what static timing is when all that is done (and make a note of it for future reference).

Geo Hahn
05-26-2012, 07:05 PM
...the points rubbing block is a bit to the right of the corner of the square lobe. It is not right on the corner. Does that mean that the timing marks are not perfectly lined up?

I think thats normal... i.e. as the points first open the rubbing block has not yet reached the peak of the lobe.

But the relationship of the points &amp; lobe &amp; timing mark is just a function of you moving the distributor so they neither confirm nor deny that the timing marks themselves are accurate (though since the engine runs they must be pretty close).

LexTR3
05-27-2012, 07:03 AM
Can someone post two photos showing the test light set up: one with the low tension wire connected (ignition on) and one with it disconnected (ignition off)? VERY BASIC, I know, but sure would be helpful.

bobhustead
05-27-2012, 07:50 AM
If your vacuum advance was oriented as in the picture and is now radically different, there is probably something wrong. Try it again. Make sure you are using the TDC mark on the crank pulley and not some random mark. The test light or buzzer method will not work with the ignition switch off or the coil to distrib wire disconnected. Electricity goes to ground thru the circuit of least resistance. When you connect a lite in parallel to the coil to points wire, the closed points provide a near dead short and your lite or buzzer has some resistance, so the juice chooses the points to go to ground. When you open the points, there is no more points circuit, so the juice goes thru your lite.
Bob

LexTR3
05-27-2012, 09:42 AM
BTW. It appears that the test lights mentioned here have two wires, with two clips (red and black?). My test light has one wire with red clip and one with a probe. What's the proper way to use this?

TR3driver
05-27-2012, 09:54 AM
BTW. It appears that the test lights mentioned here have two wires, with two clips (red and black?). My test light has one wire with red clip and one with a probe. What's the proper way to use this?
What I find easiest is to add a "clip lead" to the probe, so I can connect it to whatever without holding it in place.

https://www.radioshack.com/product/index....lterValue=Leads (https://www.radioshack.com/product/index.jsp?productId=2062661&amp;filterName=Type&amp;filter Value=Leads)

Geo Hahn
05-27-2012, 10:09 AM
Can someone post two photos showing the test light set up: ...one with it disconnected (ignition off)?

Here is how the 'ignition off' method works:

Light is just a 12V lamp with leads:

https://i1214.photobucket.com/albums/cc499/Ahwahnee18/TR4/TestLight1.jpg

One end connect to the hot side of the battery:

https://i1214.photobucket.com/albums/cc499/Ahwahnee18/TR4/TestLight2.jpg

The other end to the distributor (with the lead from the coil disconnected):

https://i1214.photobucket.com/albums/cc499/Ahwahnee18/TR4/TestLight3.jpg

That connection could also be made at the other end of the white/black lead itself if the lead was disconnected at the coil end instead of the distributor.

When the points are closed (as they likely will be when this is initially hooked up) the light will be on:

https://i1214.photobucket.com/albums/cc499/Ahwahnee18/TR4/TestLight4.jpg

The distributor is rotated CW until the points open, at that moment the light shuts off:

https://i1214.photobucket.com/albums/cc499/Ahwahnee18/TR4/TestLight5.jpg

Certainbly not the only way, possibly not the best way, but it's simple and it works.

Geo Hahn
05-27-2012, 10:21 AM
The 'ignition on' set-up looks like this:

https://i1214.photobucket.com/albums/cc499/Ahwahnee18/TR4/TestLight6.jpg

Again -- light on = points closed, light off = points open.

The igntion is on so I disconnected the primary lead at the coil to avoid the (remote, but embarrassing) possibility of the engine starting.

In case it isn't obvious, polarity (the red &amp; black leads) is irrelevant here.

LexTR3
05-27-2012, 10:26 AM
Randall and George. Many, many thanks for the explanation and the photos.

Now, then... if the lead from the coil to the distributer is NOT disconnected, am I assuming correctly that I should (1) turn the ignition switch on, (2) connect one clip of test light to the positive side of the battery, and (3) touch the probe (or second clip) to the lead (either at the coil or at the distributor) to check the points? Or am I confused....?

Geo Hahn
05-27-2012, 10:37 AM
...if the lead from the coil to the distributer is NOT disconnected, am I assuming correctly that I should (1) turn the ignition switch on, (2) connect one clip of test light to the positive side of the battery, and (3) touch the probe (or second clip) to the lead (either at the coil or at the distributor) to check the points?

That set-up is essentially the 'ignition off' method -- i.e. no need for your step 1.

I disconnected the white/black lead but in fact this is not necessary though it does prevent the engine from firing.

LexTR3
05-27-2012, 10:45 AM
George. Thanks....

BTW: Summer has hit here with a vengeance. 90 degrees and about 80 % humidity. Makes me long for Tucson weather. In this weather, I have to ride with the top up or just melt in the car... But life does have its compensations: on the east side of the Blue Ridge Mountains, in a very rural county, there's what's now called "the Brew Ridge Trail." Within the space of about 20 miles, there are four breweries (serving meals also) and several vinyards -- all accessible by beautiful, winding, paved, country roads.

af3683
05-27-2012, 11:32 AM
Timing Methods


IGNITION "ON" METHOD

Keep lead from coil to distributor connected.
Clip lead from test light to distributor connector noted above &amp; other lead to negative side of the battery (hot).
Turn ignition on.
If test light is on, turn distributor CCW until light goes off. Then turn distributor CW until light just comes on.

IGNITION "OFF" METHOD

Disconnect lead from coil to distributor.
Clip lead from test light to distributor connector noted above &amp; other lead to positive side of the battery (ground).
Do NOT turn ignition on.
If test light is off, turn distributor CCW until light comes on. Then turn distributor CW until light just goes off.

LexTR3
05-27-2012, 11:45 AM
Thanks "af3683,

As for clipping the lead from test light to the negative side of the battery (you say "hot"), I have also read that it can be attached to a ground somewhere on the engine.

TR3driver
05-27-2012, 11:47 AM
I disconnected the white/black lead but in fact this is not necessary
It may be necessary, depending on how much current your test light draws and what other loads are connected to the ignition switch. With the points open, current flows through the light, through the white wire and then to ground through the fuel gauge, ignition light, etc.

af3683
05-27-2012, 11:59 AM
Ed,

I think if you want to attach the lead to ground (or POSITIVE side of the battery) you must follow the rest of the Ignition "Off" Method steps. But I'm no expert and am struggling with this as well which is why I tried to summarize the 2 methods.

Art

LexTR3
05-27-2012, 12:46 PM
Am I completely Mixed up (possibly so) but I thought that the positive side of the battery is the "hot" and the negative side is the "ground." So, attaching somethng to the negative side of the battery is the same as attaching it to some grounding place on the engine.

Perhaps someone in the Forum can set us right on this.

Thanks for your input.

TR3driver
05-27-2012, 01:02 PM
Am I completely Mixed up (possibly so) but I thought that the positive side of the battery is the "hot" and the negative side is the "ground." So, attaching somethng to the negative side of the battery is the same as attaching it to some grounding place on the engine.

Originally, TR2-TR4 were wired the other way, with the positive terminal of the battery connected to "ground". Many people have chosen to convert; yet many more have not.

So, if it matters, it is best to be clear about which configuration you have. Talking about "hot" (meaning not grounded) and ground instead of plus and minus, is one way to duck the problem.

LexTR3
05-27-2012, 01:39 PM
Ah, Randall, as usual you have solved the mystery. Many thanks.

My car is negative grounded, so the positive pole is "hot," or not grounded. Art's car apparently remains positive grounded.

Geo Hahn
05-27-2012, 03:43 PM
I disconnected the white/black lead but in fact this is not necessary
It may be necessary...

Ah ha. When Ed posted a response that had this (white/black) wire still connected I went out to the garage to verify that it would not work like that, only to find that it did. I was pretty sure I had to disconnect it before to get a good result but decided I was just imagining that.

Your 'it may be necessary' is spot on.