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How to figure out timing when the distributor is replaced
Also posted in engine talk but this seems to be a more populated subforum.
So my buddy has an 89 F150 5.0l v8. His distributor had gone bad and he decided to replace it. Unfortunately he didnt mark anything on the old one to compare to the new one so the car wont start because he doesn't know what position the arm mark is supposed to be in. As of now it just turns over and over and obviously wont start. I'm not very educated when it comes to distributors unfortunately.
First, next time mark the dist, 2nd take out #1 plug, bring piston up to tdc, match the rotor to #1 marked on the dist, 3rd, know what you are doing, putting in a dist wrong could cause serious engine damage.
"Its a Ford. Nuff said. Everything else is just a glorified tonka toy"
"ASE" Certified" Parts Professional
92 F150 302 4x4 Long bed Extended cab
2001 Taurus wagon
2. Bump the engine until the #1 piston reaches TDC on the compression stroke.
There's a few ways you can do it. Stick your finger in the spark plug hole and get your friend to bump the starter until the compression stroke hits and it will blow your finger out of the hole. Since I work by myself, I have to bump it until I hear the "gust" or momentary spout of air sound come out of the spark plug hole.
3. Next (and this is not required, but this is what I do) is stick a screwdriver in the spark plug hole and ensure that the screwdriver does not go down into the cylinder and is touching the top of the piston.
4. Next, look at the timing marks on the harmonic balancer to make sure it's near or on the bracket that is used to set the timing.
5. Next, indicate the "1" that is on the distributor cap and position the the tip rotor button where the "1" will be after you put the distributor cap back on.
Note: You may have to insert and remove the distributor a few times to get the tip of the rotor to line up. Also, you will have to turn the rotor button a little bit forward or backwards from the "1" because it will turn once the gear on the distributor touches the camshaft. But once you insert the distributor, the tip of the rotor should be EXACTLY under the "1" on the distributor cap. Be patient with this, it takes a few tries to get the hang of it when sticking it in and removing it to set it.
After this, put the cap on, the #1 spark plug back in, hook up everything else and it should fire right up!
1990 F150 XLT Lariat - 2wd
302/5.0L - E4OD | 3.55 Gears - Non-Limited Slip | Stock GT40 Heads | .030 Over (Speed Pro H120CP30 Pistons) | T-Moss Ported Lower Truck Intake | Comp Cams XE258HR-14 (35-512-8) | Hedman Shorty Headers | Will install my Trick Flow 58cc heads when I quit being a lazy bum.
Suggest good advice thus far - but throwing my two-cents' worth in - setting the dizzy at the No. 1 position with the crank at TDC means you have a 50/50 chance of being right. Given my experience and related luck, there's a 75% chance of being wrong.
Bumping the engine around with the starter is always iffy and time-consuming - much better if you have a socket to drive things around.
At any rate, get things lined up for the #1 rotor mark on the dizzy at TDC on the crank and give 'er a whirl. If there's snorting and backfiring - suggest the dizzy is 180 degrees out. Roll the crank around 1 time to TDC so that the dizzy rotor is 180 degrees away from the #1 mark on the cap, then reset the dizzy to again align with the #1 mark. Should be good enough to light off, then can set the timing proper.
To make a long story short. I have done everything by the book on replacing a distributor in my 96 f150 5.0. I took my fan and belts off to set timing with a timing light with the spout bar removed. I set it to 10 degrees BTDC. Reapplied spout bar. Cut engine off put my fan and belt back on and now it has a little pop to it. What do I do?