Look here for help first!Removing the distributor to replace the vacuum advance
And getting it back together with the correct timing
Is not difficult if you take a few prep steps
Remove distributor cap
!!!!Manually!!!! with a ¾ or 19 mm socket (depending on model year)
Rotate crankshaft to get the number one cylinder to the top of its compression stroke
The crank pulley timing mark will be at zero degrees (degree mark on plastic shroud) (about 1 o’clock position)
The distributor rotor should be pointing nearly northwest (looking straight at distributor from drivers side)
It will actually be slightly below northwest
If it is pointing southeast you will have to rotate the crank pulley one complete revolution
I place a small piece of masking tape on the distributor to mark the rotor location
Remove distributor
Do not rotate engine crank until after distributor is reinstalled
When reinstalling you can shove the distributor in and out until the rotor lines up in that northwest position
If for some reason the crankshaft was rotated while you had the distributor out
You will have to get the number one piston back to the top of its compression stroke
Unfortunately you will not be able to tell very easily when this is so.
When the crank pulley timing mark is lined up at zero degrees the number one or number four piston
could be at the top of its compression stroke
I only know of two ways to determine which one is which
One method is to pull the valve cover and check the valve rockers
When the number one piston is at the top of its compression stroke the first two cam lobes will be pointing downward and the first two rockers will be loose
If one is tight rotate the crank one complete revolution and recheck
The other method is to remove the number one spark plug and plug the hole with toilet paper
When you !!manually!! rotate the crankshaft the compression will push the toilet paper out
You could also plug the hole with your finger while someone else rotates the crank
You will feel the air pushing your finger out
When you have it all back together check to see if you removed the tool that you used to rotate the crankshaft. Starting the engine with that tool down there may rip the bottom of your radiator apart.
My Tercel vacuum advances have the three ports
I hook up the bottom one
And the top inboard one
It has a larger hole
The other top port has a small hole and I believe it is for the high altitude thing
Being at sea level I do not use it (plugged)