Timing Chain Replacement 85 Carrera
 

I am in the process of replacing a very stretched out left timing chain on my 85 911 Carrera. The first step was to find TDC for cylinder 1 which I did by turning the crankshaft till it lined up with one of two marks that are about an inch apart (unfortunately the factory neglected to stamp Z1) on the crank pulley and putting a welding rod into the spark plug hole of cylinder 1 and checked to see when the piston was at TDC. The concern I have is neither the camshaft or the distributor is in (from what I have read ) in the exact position it should be. The camshaft marking "930" is pointed more at 10 o'clock than 12 o'clock and the distributor rotor is about a half inch right of the mark. With 2 out of 3 marks off I am afraid that something is wrong and even though I am going to re-time the camshaft I might not get it correct. I am enclosing some pictures so maybe somebody can provide some advice. Thanks John http://forums.pelicanparts.com/uploa...1436559630.jpg

timing chain 85 911
 

Another picturehttp://forums.pelicanparts.com/uploa...1436561175.jpg

timing chain 85 911
 

The chain isn't the problem. I don't know how you're running.
The rotor should be coming up on to the mark. You're one cog on the bottom of the distributor
The cam is definitely off location..like I said, I don't know how you're running
The keyway on the cam, if it's the left cam, is supposed to be up, as they should both be at this point.
There is 2 large holes in the pulley, they should be vertical giving you a mark that you can put fingernail polish in.
What is the relationship to the other cam to the one in the picture.
Bruce

You point out some good indications that something isn't quite right with the timing.


1. The crank pulley is the most common point of reference. But its not always 100% accurate. If you can located another pulley to compare the markings, that might help. I have a friend who's got an original '87 3.2 two row pulley that you might be able to borrow.

2. The 3.2 Motronic engine is fired by the ECU and the distributor isn't necessarily going to be right at the #1 mark on the distributor housing to fire. That said, your distributor looks like it could have been installed with it being one crank tooth off the mark.

3. The 930 mark on the cam is just a reference point to start the cams at a baseline position before actually timing the cams. When you do the actual timing of the cams, the 930 mark does not end up at 12 o'clock. However, if your distributor and/or crank pulley are off a bit, that would change the position at which someone would set the cam when timing it.

You could get a common degree wheel from a speed shop/Summit/Jeg's/wherever and get your TDC started dead right on for certain.

There is a pin on the pulley that locates at 9 o'clock on the crank point. I have seen the pin wear into the crank and make it hard to time if you are unaware of the problem.
Bruce