How to find initial timing for distributor install?

[timdog]

I have a 66 Mustang with 200ci and DUI distributor.

Long story short, I took the distributor out and totally lost the timing. I now can't get the car to start or even know where the timing is at.

I don't know if the timing mark on the crank is correct - with a timing light, the engine used to run well with it about 20 degrees before TDC.

I tried getting the timing mark back to about where it was at, then pointing the rotor to the #1 cylinder spot on the cap. It started but ran HORRIBLE - sounded like the engine was going to tear itself apart. I stopped and tried again. And again. Maybe I was 180 degrees out on timing?

Tried rotating the engine 180 degrees and then pointing the rotor at the #1 cylinder again and it wouldn't even start. Sounded like it was back firing out the carb? Maybe the engine was flooded? I fumbled around for an hour, trying different things until the battery needed to be recharged.

I gave up for the night and had a beer... hopefully I'll be more clearheaded and less frustrated tonight.

Any advice on where to begin? How can I figure out whether the engine is at TDC or BDC? How would I install a distributor if an engine where I have no idea where I'm at?

 

[FalconSedanDelivery]

easy way for an inexperienced tool shy beginner , first take all the spark plugs out , get a good ratchet and socket that fits the damper bolt, put your thumb over the number one spark plug hole, turn the engine over , you will feel the piston push your thumb out as it expels the air , that assures you are on compression stroke , then get a long screwdriver , straw , etc put it in the plug hole , turn the engine till it pushes the object up as far as possible , look on your damper and see if you can see the little notch , if its not close it has slipped , no matter then back the engine up with the wrench approx 1 inch and install the Dist with the rotor pointing at number 1 , keep in mind the helix on the gear will move the rotor a bit , the best is to have the rotors leading edge just under the number one terminal , good luck

 

[thesameguy]

I was always taught to mark the damper as the screwdriver stops moving up, but to keep turning and then mark the damper again just as the screwdriver starts to go back down. Halfway in between actual TDC... the piston will hang out at the top of its travel for several degrees, so if you mark when the screwdriver stops moving up, you've probably actually found a couple degrees before TDC, not actual TDC.

 

[CobraSix]

I keep meaning to make a video of my method and hosting it. Maybe when my move to Texas is complete I'll have time to do so. It's extremely accurate.

Basically, here is what I do:

Tools:
1) Long telescoping magnetic wand
2) 5' 2"x4" (or anything that'll span the fenders)
3) C Clamp
4) 36" straight edge ruler.

Method
1) Install the Dizzy

2) Take #1 plug off, find the compression stroke as falcon six described.

3) but the 2x4 across the fender, nearly on top of the #1 plug hole. Attach the ruler (or straight edge) with the C Clamp to it. I find it helpful to line the edge of the ruler with masking tape.

4) rotate the crank so the piston is visible.

5) Insert the wand and extend it so that the end overlaps the straight edge.

6) Now rotate the crank slowly until the wand does not move any further down (it'll move down if you have it in correctly).

7) Measure between 1/2" to 1" (or any distance really) up from that point and mark it with a pencil.

8) Continue rotating the crank until the wand lines up with that mark.

9) Now reverse the crank rotation, and carefully count the number of rotations to go from the mark, to the lowest spot and back to the mark. I find it very helpful to make sure I do full 90* rotations with my socket wrench. Remember this number.

10) Now reverse rotation back again and count the number of rotations (Again, I count the number of 90* crank turns I make with my ratchet). This number should match #9's number, or be very close (within a very small variance). If not, repeat 6-10.

11) Now divide the number in half, and reverse the crank rotation by that amount. That will be extremely close to TDC.

I've made this method similar to doing alignment procedures for marine work. Trying to find the absolute top on a piston movement is near impossible since here exists an arc of about 10* of crank rotation where the piston actually is nearly motionless but obviously 10* is a lot of error. By going a preset amount away from TDC and measuring the rotations from it, you can get nearly dead on.

 

[JackFish]

I'll add a remote starter to the tool list.
Makes it real easy to just bump the engine a little bit.