Timing Questions

'97 4.0,

messing around with ignition systems tomorrow at school,

need to pull all plugs, wires, cap, rotor, distributor and then get it back

together right withing a certain amount of time.

was wondering what the correct timing should be.

searching I've heard 12 degrees BTDCC at idle?

not looking to adjust (is it even adjustable?), just want to know
what it should be.


also, how do I disable the timing advance?
controled by computer, not vacuum, right?

The comp controls all the timing.There is no advance in the distributor(springs/weights/vacume).Even the housing cannot be turned as the bolt and slot are a fixed size.
You can move the cam and distributor gears about one tooth either way and have the motor run--not well, but it will run.
As with all motors,bring to TDC on compression,pull cap note location of rotor,loosen hold down bolt,pull dist out -note direction and location of rotor when out of gear mesh--If you do not rotate engine the install is just the reverse .
Wayne

Just remember that when you reinstall the distributor the helical gear will turn the rotor a few degrees as you push it in. As Wayne notes, if you don't move the engine, it should be pretty easy to get it back right; just don't settle for a rotor location other than what you marked and try again. If for some reason the assignment requires that you disturb the engine as a way of making you re-establish timing, make sure that you set the crankshaft to a specific mark before removing the distributor, and put it back to that mark carefully before reinstalling, and make sure you rotate the crank the right way so that you take up any chain slack, because unlike conventional distributors, you cannot compensate for a minor error simply by turning the body. There really is only one position in which it will work right.

Ur quote:
messing around with ignition systems tomorrow at school,

If you have to pull the distributor...mark the rotor position first to number one.
Use some paint on the housing. But you shouldn't need to take it out unless you are rebuilding the engine. That is a skill for the rebuilding class not tune-up class (or old school). Do one on an engine that can be timed so you can learn to time an engine. Just my $.02 .