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Gleamed from the wisdom of others, I offer the definitive methods of finding TDC.

This is a necessary first step for various tune up and installation procedures.

Cam Gear Method Proper:

*Tii owners. If you are concerned about your injection pump timing.. You will want to remove your injection pump drive belt and align the pulley/timing cover marks after this procedure, and then reinstall the drive belt.

1. Remove the valve cover.

2. Remove the spark plugs.

3. Hand turn the motor grabing the v-belt, rotating clockwise as you face the grill, or by rolling the car in gear.

4. There should be a small notch on your cam flange, nearly hidden by the sprocket, using the method(s) in step 3, line that up with the oiling bar and you're at TDC on the compression stroke. (Both valves should be closed on #1 cylinder.)

5. If there is a distributor installed, there is a notch on the distributor lip under the cap indicating the position for the first cylinder. The rotor should be pointing in the general direction of this notch. ** If your motor was timed correctly prior to this procedure, the rotor should be slightly counter clockwise of the notch.**

6. There are TCD marks on the crank pulley, and a pointer protruding from the timing chain cover, these should also line up as confirmation.

7. Do what you came to do, and adjust the valves while your in there.


Tii injection pump alignment:



Cam Gear "Quick" Method:

(You don't have to remove the valve cover)

1. Align the crank pulley notch with the pin. It's real hard to see, marking both with white paint will help a lot.

2. Remove the oil cap and feel if the intake and exhaust rocker of cyl #1 are loose (just like with measuring valve clearance)

If they are, you're at the right TDC, if they're not, just spin the crank another 360 degrees.


And for anyone running the REV limiting rotor button, DO NOT mistake the ground post for the rotor contact, as seen aligned INCORRECTLY in the picture below. It CAN happen.






Thanks to MMII73, C.D., Bill Williams, Sislane, 4X2, Rover1, and Ken.. for the M Zen.

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  • 5 years later...

thanks for this...


My engine is out of the car and on a engine stand....


What if you have an aftermarket cam (I apparently have the IE 292), I did not see any markings on the cam shaft.


When I removed the chain, I made a mark on the chain & cam sprocket to show where it was located and I did the same for the chain & crank sprocket.


After I cleaned everything up, I lined them up. Could there be a way things are messed up if my marks on chain and crank/cam sprockets line up?


- I wouldn't  think it matters because I would assume the cam lobes decide it when you re-assemble the 2.

BUT just in case, let's say when i took off the head, the pistons were on "intake" and  i cranked block once then lined things up (and then the pistons were on the "power" stroke, would it matter? or it's simply decided by cam.


Now in order to put my distributor back on (i didn't mark that :() I figure I need to put it at TDC and put the distributor pointing to #1 (the marking) am I right?


- I'm going to use a skinny bar through the spark plug hole to make sure I got TDC highest point (when valves are closed).



I should have done more homework before starting everything.

Edited by MildSeven
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Now in order to put my distributor back on (i didn't mark that :() I figure I need to put it at TDC and put the distributor pointing to #1 (the marking) am I right?


- I'm going to use a skinny bar through the spark plug hole to make sure I got TDC highest point (when valves are closed).



You are right here, but only if you are aware that when you first start to insert the distributor the mark on the rotor will not be pointing to the mark on the distributor upper circumference...if installed correctly it will end up that way only AFTER IT IS FULLY INSERTED and seated (the rotor rotates as the distributor is pressed home because the gear at the bottom of the distributor shaft engages with the gear at the rear of the cylinder head).


Regards, Maurice.

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  • 1 year later...

I just wanted to make a clarification to this thread as it was a bit confusing for me.  The line on the cam gear that represents TDC is the more prominent line after the 2.  It was a bit unclear in the photo posted above.  I basically got it to just before that line, then bumped the car until I saw the line in the flywheel view, which corresponded to that line being right in the middle of the oil bar.  In the photo below, I am just showing the line, not when it is at TDC.


Edited by mataku527
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  • 3 years later...

So I know it’s been beat to death, but this is the most intricate work I’ve done on a project and if it’s not right, things get expensive for me.


can I get a “looks right” from a few of you to make me feel better?


see photos of my head and block as I am ready to mate the two.








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  • 1 month later...
Posted (edited)



Lost my text first post.. was just thanking EurTrash for this relevant post. I am doing valve and distributor work and was so excited last night I installed new plugs and put on valve cover and torqued. But then I woke up this morning in cold sweat thinking "You dumbass.. you never set TDC using cam flange/oil bar alignment!!" But his crank pointer and feeling #1 rocker idea saves my day 



Edited by worzella
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  • 4 weeks later...

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