Top Dead Center

I’m trying to set the timing on a F134 there is no timing marks to be found .if I use my finger to feel for it to stop pushing air and look at the rotor it’s pointing at 11 o’clock instead of 5 o’clock am I correct in assuming the distributor is a 180 degrees off or do I need to turn it a bit past when it stops pushing air out of plug hole just checking with the experts to refresh my failing memory.

 

They can be hard to see. A good light and a careful cleaning revealed mine.

 

Mine has a small notch on the outside lip of the crank pulley, but if you can't find it, don't worry too much. Put a screwdriver through the plug hole and move the crank back and forth until the screwdriver is at his highest point and mark that spot on the pulley and the timing cover. Chances are if you look close after the screwdriver trick you will find the mark on your pulley. Put your #1 plug wire on the distributor at that point and you will be pretty close. Depending on how the oil pump was installed or which distributor you hav e, #1 could be at 5 o'clock or 11.

 

Was the engine running before you started to adjust the valves?

If so, the wire going to the number one cylinder on your Jeep should be in the 11 o'clock position you found the rotor pointing to with your thumb compression test. As David said the distributor position depends on how the oil pump was indexed. It could end up at any of the four positions. However I do not see how the screwdriver method would work because the spark plug hole is not over the cylinder.

Once you determine you do indeed have #1 at TDC, here is one way to adjust the valves.

Here is a simple way to do it, I call it my 12 step program.


1) Remove all spark plugs, disconnect the battery, and place transmission in neutral.


2) Mark the #1 position on the distributor body with a light colored Sharpie or chalk.


3) Rotate the engine clockwise with a socket wrench until the rotor is pointing at the mark, easier if you have a helper to watch this while you turn the crank. The distributor rotor will turn counter clockwise. When the rotor is pointed to the #1 firing position it is a few degrees BTDC but both valves will be closed.


4) Make a mark parallel to the ground on the passenger side of the crankshaft pulley.


5) Adjust the valves for #1


6) Rotate the engine 180 degrees until the mark made in step 4 is parallel to the ground on the driver side


7) Adjust the valves for #3


8) Rotate the engine 180 degrees until the mark is parallel to the ground on the passenger side


9) Adjust the valves for #4


10) Rotate the engine 180 degrees until the mark is parallel to the ground on the driver side


11) Adjust the valves for #2


12) Done. Replace the tappet cover, spark plugs, cap and wires then start the engine.