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[JohnMWeber]

Hello everyone I an new to the Auto world..My question is how do you find TDC for timing purposes without the proper marks on the pully?  I have the "V" notch but I believe it is off.  Thanks for the help.

[Bookwus]

Hiya John,

Welcome to our little corner of the VW world!

Truth be told, there are a couple of ways to determine TDC.

1.  Pull the plug on your number one cylinder.
Pull the cap on your distributor.
Rotate the engine so that the rotor tip is pointing at the position for your number one cylinder spark plug wire.
Insert a pencil (eraser end first) into the number one spark plug hole.
If it makes immediate contact (the piston head) you are at TDC.
If it does not make immediate contact you are the firing position for the number three cylinder.
Rotate the engine 360* so that the rotor also swings completely around 360* to the same spot.
Insert a pencil again and this time you should immediately contact the piston head.  You are at TDC.


2.  Pull the cap on your distributor.
Rotate the engine so that the rotor tip is pointing at the position for your number one cylinder spark plug wire.
Pull the valve cover off the right side head.
Check to be sure both intake and exhaust valve rockers are loose.
If both are loose you are at TDC.
If either one is tight against the valve stem you are in firing position for the number three cylinder.
Rotate the engine 360* so that the rotor also swings completely around 360* to the same spot.
Both number one cylinder valve rockers should now be loose.  You are at TDC.

[JohnMWeber]

just to make sure is that so it points to the #1 spark plug?  Then I should be able to make a mark on the pully to use with a timing light, correct?  Or do I time off of the V notch?
Thanks

[Bookwus]

Hiya John,

As to the rotor...........   just make sure that the rotor tip is pointing at where it would normally touch the number one contact point in the distributor cap.  That should take care of that.  More than likely you'll also notice a notch in the top edge of the distributor body in that area.  The notch signifies the spot for the number one cylinder contact.  The reason I didn't mention the notch before is that 1.  it is not always present and 2.  it can be found in other orientations IF the PO has messed with the distributor set-up.

As to marking the pulley.........  once you have determined your TDC you'll want to head down to the Technical Information forum (at the bottom of the VWAR index page) and look for either the Distributor Basics or Distributor Basics 2 threads.  These threads will tell you what the timing specs for your car are (assuming here that you have OEM equipment).  Once you find out where the timing mark is for your car you can go ahead and paint it in on the main pulley.

A word or two.......  Most of the main pulleys with which I have worked have a notch at 7.5 BTDC (some have a second notch at 10 BTDC) and a dent in the forward rim of the pulley at TDC.  I'm using an SVDA (non-stock) on my 70 Bug.  It wants to be timed at 7.5 BTDC so I have that notch painted.  And I have a similar paint mark (two stripes actually to differentiate it from TDC) 180* out from the TDC mark.  That second mark allows me to set up the engine to set valves on cylinders number two and four.  Very handy.

[JohnMWeber]

Thanks I will have to take some pics because I know the Distributor is not OEM but does have the notch in the base.  I will look for more markings in the pully and see what I can figure out.  Thanks for the info.