Edward1

HI

I am trying to set the timing on my 1966 912 and seem to have a problem locating the TDC mark. There are two marks on the pulley(the marks are very distinct). How can I tell which is correct? Next is I don't seen any markings to indicate the 28° - 30° advance mark, what side of the TDC mark woudl this be? Using the timing procedure found on the @ http://www.petry/markp/912tuneup.htm I get a little confused with this procedure and the one shown in the 912 Porsche book (the gold book). Can anyone offer a simplified discription of timing the 912. This is the first time I set the timing on a Porsche. Anyones help would be greatly appreciated.


Edward

hoffman912

rotate the pully to one of the marks, take off the valve cover for the passenger side. see if you can move the rockers on the 1st cylinder (both intake and exhaust). also see if you can spin the pushrods with your fingers..if the rocker arms can move and you can spin both pushrods for #1 you are TDC.

if not.. rotate pully 180 tto the other mark and try again.

when you find that you can do that and are on tdc, mark the pully with a dab of pain or somthing so you know for now on which one is tdc

Edward1

Thanks so much for the information.


Edward

Edward1

Hi

Thanks for taking the time to answer. I am getting confused with the information on the web site indicated on my first message. He shows on his diagrams that the engine rotates clockwise and shows an arrow indicating this, yet on several other replies I've gotten on the the 912 Board they indicate the engine runs counter clockwise???? Have you read the instructions furnished on this site and agree with his statements?

Again, I really appreciate the help. Unfortunatly there are no Porsche shops in my home town that I can bring the car to and the car is not yet licensed for the road.

THANKS


eDWARD

hoffman912

when doing a valve adjustment you rotate it counter clock wise (which is the same method of how im telling you to locate tdc -by rotating it until you find the #1 valves are closed, which is when you can wiggle the rockers in and out, and when you can spin the pushroads with your fingers).

im basically telling you the same thing John is. John knows his stuff.

Edward1

Hi

At the risk of making a pest out of myself, I have one more question. Once the engine is at TDC the range indicated, 0 TDC to 28-30 degrees represents 0 degrees to 30 degrees after TDC or before TDC? If it is after TDC then the 0 to 3 degree would be set before the TDC. Please correct me if I am incorrect.


Thanks again.


Edward

Peter Zimmermann

Edward: Here's what you do:
1. Set your point dwell angle to approx. 47 degrees.
2. Hook a test light from the wire on the distributor side of the coil to ground. An alternate tool can be made from wire and a 12V bulb, but you'll need more hands than you have to do the job!
3. Remove distributor cap using its two metal clips.
4. Turn on ignition.
5. Rotate engine clockwise using the crank pulley bolt until your Z1 (TDC) mark gets close to the groove on the timing cover (you will see that your rotor will point toward a small groove in the distributor housing where the base of the cap normally sits against - that's cyl. #1). Your test light should turn on approximately 4mm BEFORE the TDC mark on the pulley reaches the timing cover mark. If it doesn't loosen the clamp bolt at the base of the distributor and move the distributor as needed. When you have it right gently snug the distributor clamp until the distributor won't turn.
6. Done.
7. Yes, you can create a mark to check advance by using a basic measurement of 3 degrees = 3.6 mm on the pulley. Or buy a timing light with degree setting capability. Or you can drive the car, if it accelerates strong, and does not ping, you're "probably" OK.
Pete