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I get tired of typing this, and figured this was the best post I could do for a step by step on how to properly set timing on a 302 or 351 in a technical write up.

This is my routine and works every time.

These first steps are to be able to fire it up without a timing light. These first directions are for new motor installs, or if you've pulled the distributor and didn't mark the distributor before removing it.

This is step by step for a 302 or a 351

Step one.
Make sure auto trans is in Park and parking brake on, or if it's a manual trans in neutral and parking brake on (safety first). And leave the key removed from ignition as you don't want the engine to start while using this process.

Step two.
Make sure your timing marks are clean and can be read. These are located on the harmonic balancer. Clean them up with a wire brush or some sandpaper. Mark 10* BTDC with a white/yellow crayon. There will be two 10's showing, you want the red 10 below. The marks will look like:

ATC10||||0||||10||||20||||30BTC (Each "|" represents 2 degrees)


Step three.
Pull number one plug. It's the front plug on passenger side.

Step four. (This is where step one is IMPORTANT, if you don't believe me, go ask Garlic Bronco :doh0715:)
Using a screwdriver, bump the starter relay. When doing so, put a finger over the plug hole. As soon as you feel the big gush of air.......


Step five.
Locate your 10* BTC and this should be relatively close to your timing pointer. It might be before or slightly after. If it's before (spinning in clockwise direction), turn it so the 10*BTC lines up with the pointer like so. If it went past the timing pointer, then you can either turn it counter clockwise to meet the mark, or spin the crank so that the 10*BTC mark passes the timing pointer once (going clockwise) and stopping on the timing pointer on the second spin (clockwise).



This should be number 1 compression stroke.

Most people will recommend stabbing the distributor at 0*TDC. This thread is about how I do this, every time.

Notice something here. And this is why I do this at 10*BTC and not 0*TDC:
ATC10||||0||||10||||20||||30BTC<------notice 10*BTC is centered
ATC10||||0||||10||||20||||30BTC<------notice 0*TDC is not centered.

If stabbing the distributor at 0*TDC, and positioning the distributor so that the ignition module(if equipped) is pointing at a 45* (towards driver's headlight), then the stab wasn't centered. Positioning at 10*BTC, your centered on the timing marks, and centered on the stab of the distributor. This allows maximum EQUAL advance and retarding on the timing. Not more one way than the other which in turn can affect you getting it running on the first time.

Step six.
Grab the distributor and cap, and make a mark on the distributor plastic base for contact number one. This mark will be in the same spot as in this picture. Going by the screw in the picture, number one will be just to the left of the screw as seen by the black mark in the picture. Make a mark like so.



Step seven.
Time to drop the distributor in. Start the drop so the rotor is to the left of the black mark, ignition module at 45* angle. Now when the distributor gear marries the cam gear, the rotor will spin clockwise. You want to drop it in so the left tip of the rotor is about to make contact with the black mark like seen in the picture below when the distributor is fully seated. This will be real close to 10*BTC. And you'll be able to dial it in once running with a light. You also want to drop it in so that the ignition module (if equipped, if not, flat spot on distributor) is pointing at a 45 degree angle. Basically, aim it so it's pointing towards the driver's side head light. This will allow you maximum room to turn distributor both directions when setting final timing with a light. Then tighten the hold down bolt snug so the distributor turns but not to easily.



If you have the distributor fully seated into the block, and rotor positioned as shown in photo above (left tip rotor meets contact point of number 1) then it's time to wire it up. If distributor isn't fully seated, it's most likely because the oil pump shaft didn't slide into the distributor. If this happens, turn the crank with a 15/16 socket & ratchet and it'll drop in once the distributor turns. Won't take much of a turn. Then tighten the hold down bolt snug so the distributor turns but not too easily.

Step eight.
Replace cap and wire it up. 13726548 is the Windsor firing order. 15426378 is the older 302 and non HO motors firing order. This may vary due to cam changes. But will be one or the other.

Now verify firing order again. Fire it up. :thumbup

If it runs good, time it with a light with the spout unplugged. :twotu:
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Now if you get a backfire, you passed up compression stroke for cylinder one. Your 180* out. Proceed to step nine.

Step nine.
Pop the distributor cap, turn crank so the so that 10*BTC is lined up with the pointer, if rotor is pointing to the other side of the distributor 180* from black mark (cylinder 6), pull the distributor and repeat steps 7 and 8.

If rotor is pointing to number 1 (black mark), spin the crank once (so rotor is pointing to number 6 cylinder) and line up 10* BTC, pull the distributor, and repeat steps 7 and 8.

Good luck, this should get you going.

Photo's above, courtesy of Doomsmith :twotu:


Timing with a light.....

The timing light will have three connections to it. One goes to positive battery cable, one goes to negative battery cable, and the last will go onto the number one spark plug wire. Connect the timing light up. There are two types of timing lights. One has a dial, one does not. (VERY IMPORTANT----->) If your using a light that has a dial, make sure the dial is at 0 degrees. If it's not at 0*, then your timing will not be set right accordingly to these instructions. The dial is another way to read the balancer if going by a mark that's at 0* TDC. It's in more details and I'm not going to explain using the dial in this thread......yet (post 12).

------->Make sure all wires from timing light are away from the fan.<-------

Now pull the spout connector or pull the vacuum line off the distributor and plug the line.

The spout will look like this for the ones that's near the distributor (84-91).




For the later models (92-96), it could be near the driver's side fender, as the ignition module was removed from the distributor. Here's a picture of this.




Or the vacuum line from the distributor




Start the motor.

The timing light will have a trigger. Aim the light towards the timing pointer, and see where the yellow/white mark on the 10* BTC that you made is at. It helps to have the truck partway in a garage to darken the surrounding light so you can see the timing marks every time the light flashes.

Next, if the mark is off by a little bit, turn the distributor so the mark lines up with the pointer. And tighten the distributor down tight. Recheck again after the distributor is tight. If the mark is lined up where you want it, replace the spout connector.

Sixlitre tuneup
If doing the sixlitre tune up, you'll want to make your mark on the 12* or 13* BTC instead of ten. I've made 12* and 14*BTC red so you can see where you'll need to line up the pointer for the sixlitre tune up. 13* BTC is between the red marks. ATC10||||0||||10||||20||||30BTC (Each "|" represents 2 degrees) Or just know that you'll want the 10*BTC mark to be just under the timing pointer (hidden).

NOTE: This method will work on most V8's, not just the 302 or 351. I've used this method on a buddy's 460, and had it running within minutes. Timing any motor should be done basically this way.
 

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Discussion Starter #2

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sackman9975:

Great write up Brother!


With regards to step #5, once you bring the piston to TDC wouldn't it be better to set the harmonic balancer to 0 (zero) first, then stab the distributor, rotate the rotor CCW to point to #1 lead on the cap, wire up the firing order etc..then fire it up and re-time it.......?

Just a thought....:thumbup
 

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Discussion Starter #4 (Edited)
sackman9975:

Great write up Brother!


With regards to step #5, once you bring the piston to TDC wouldn't it be better to set the harmonic balancer to 0 (zero) first, then stab the distributor, rotate the rotor CCW to point to #1 lead on the cap, wire up the firing order etc..then fire it up and re-time it.......?

Just a thought....:thumbup
Thanks Jean. I edited the first post, step five, to give explaination to this.

If you've ever timed a motor at TDC, you'll know it doesn't run very well as the ignition will not be at a compressing stage, it'll already be compressed. You want the plugs to fire when its at its best. Setting it at 10*BTC will get the motor running faster with less playing with the distributor. Plus setting it at 0TDC, you might not hit the right tooth of the distributor.

Although you could do it at TDC, but really this write up is the best way to get it fired up with less mistakes, and you'll be on the right tooth of the distributor. :thumbup

If your threading a needle, you want the string to go through the hole, not off to this side. Same concept, stock timing is at 10*BTC, you want to be as close as you can. 10* is a lot when it comes to timing.
 

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Nice job Sackman. 1 question - shouldn't you warm the engine up before you adjust the timing? I know the spout is unplugged so the computer won't mess with the timing, but I'm not sure if the system needs to be in closed loop to get an accurate measure.

Know what I'm saying?
 

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Nice job Sackman. 1 question - shouldn't you warm the engine up before you adjust the timing? I know the spout is unplugged so the computer won't mess with the timing, but I'm not sure if the system needs to be in closed loop to get an accurate measure.

Know what I'm saying?
Thanks Josh. :twotu: I figured in two years of being here it was time for me to do a real write up. And timing is one of my favorite things to do. I've been called upon many times by friends to fix timing issues. And when I'm called upon, their vehicles are usually running within minutes.

The timing is not affected by a cold engine. This can be done either way, cold or warmed up, you'll get the same results. A fresh built motor just dropped in isn't warmed up before doing this procedure. You still gotta get it started. ;) :thumbup
 

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When I stabbed the distributor the engine was brand new so I went with what the builder indicated because I'd never done it before, talk about OJT...lol lol ....

So maybe setting the HB at 0 (zero) after the #1 piston is at BTC is old school....but you're saying I could have just set it at 10* on the HB and it will fire right up....on 0 it fired up with out any problem with the exception of replacing the "starter relay"...lol lol....PITA..

OK, good to know.....:doh0715:

Thanks Brother! ~ :thumbup
 

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When I stabbed the distributor the engine was brand new so I went with what the builder indicated because I'd never done it before, talk about OJT...lol lol ....

So maybe setting the HB at 0 (zero) after the #1 piston is at BTC is old school....but you're saying I could have just set it at 10* on the HB and it will fire right up....on 0 it fired up with out any problem with the exception of replacing the "starter relay"...lol lol....PITA..

OK, good to know.....:doh0715:

Thanks Brother! ~ :thumbup
I'm not saying that stabbing at 0* won't yield a start up, I'm sure it will. This is how I've always done it without issue. Once running, it's usually a real small twist of the distributor to get it at it's mark.
 

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This may sound like a dumb question but when a timing light is advertised as being a 'timing light with advance'. What does that mean? How is it different from just a regular stock timing light?
 

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This may sound like a dumb question but when a timing light is advertised as being a 'timing light with advance'. What does that mean? How is it different from just a regular stock timing light?
The difference is in the dial. You can actually set the timing by using the dial. It makes it easier to see the timing marks, as the marks are on the dial.

Using the advance timing light, there will be degrees on the dial. To use it, you must mark 0*TDC on the balancer. From there, if you turn the distributor, the TDC mark will move. But by turning the dial, the 0*TDC will move back to the pointer, then once 0*TDC is lined up, you read the marks on the light. This tells you where your timing is at instead of the balancer. It's a little more "advanced". You gain nothing from one of these lights except to be able to read the balancer from your hand. And using one of these light's, is really for the more experienced. Not used properly, can result in timing being off.
 

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Hi sackman,
that is great information, i turn the distributor, the TDC mark will move. But by turning the dial, the 0*TDC will move back to the pointer, then once 0*TDC is lined up, you read the marks on the light. This tells you where your timing is at instead of the balancer. It's a little more "advanced". You gain nothing from one of these lights.That is very much effective.
Thanks for sharing it sackman.
 

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Hi all that have posted here. First off, this has been the most detailed post I have read. Thanks Sackman. Now, I just took a look at mine and the 10BTC is a quarter turn clockwise on the HB. which would meen, I would have to turn it counterclockwise a quarter of a turn if not more to get it in the right position. Is this normal?
My problem is, the vehicle was stolen and recovered. After that I had no seats for the vehicle. (they stole my custom made seats) It has been about a year now and i have seats but when I drive, it bogs really bad, losses all power and when i hit the breaks it dies, but will die without hitting the breaks. I have been doing research and some say it might just be water, some say the cat might be plugged but others say it might be the ignition module. Now I am reading this and think the timing could be off.
specs.
302, 5.0l efi 89 xlt

can anyone help????? I can't afford to take it to a mechanic but can't afford not to have it right now.

In desperate need of help.

SWBC

Thanks in advance
 

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I have a question. When i set the timing, i take out the plug, set the timing, start it up and turn on the timing light and it says its on mark. But then when i put the plug back in, the timing no longer lines up with my mark. it drops but several marks and runs rough and back fires, but if i unplug it again it goes back to the right timing. what could cause this?
 

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Help cant find the timing pointer, I found 10BTDC on the balancer, and I really cant get a good view of the balancer from the top, I put a thin piece of reflective vinyl stripe on 10BTDC so hopefully I can see it with a timing light, but I cannot figure out where that needs to align to.
Thanks
 

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Help cant find the timing pointer, I found 10BTDC on the balancer, and I really cant get a good view of the balancer from the top, I put a thin piece of reflective vinyl stripe on 10BTDC so hopefully I can see it with a timing light, but I cannot figure out where that needs to align to.
Thanks


Duz that help ya illuzion ?

Sixlitre
 

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I have an emergency procedure for this that I'll add:
If the motor has incorrect, missing or otherwise unusable timing marks, and you absolutely have to get it running anyway; you can crank it till you get the big gush of air, then place a long thin object(at least 8"-10" long) down the plug hole and turn the motor over clockwise by hand until you see the object stop rising. At this point, you know the #1 piston is close to TDC, and you can drop the distributor in. Remove the object from the #1 plug hole and re-install the spark plug and wire. Retard the timing slightly before starting to avoid carb backfire by turning distributor counterclockwise 1/2" or so. Fire it, and then advance the distributor slightly until it idles ok. I've done it in emergencies, such as alongside the road, and it will get you home. (NOT a permanent timing solution)
 

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"Step four. (This is where step one is IMPORTANT, if you don't believe me, go ask Garlic Bronco )
Using a screwdriver, bump the starter relay. When doing so, put a finger over the plug hole. As soon as you feel the big gush of air......."


I have to do this... after pulling my distributor to replace ign control module and pick up coil its starting now but not running right. I can tell the timing is off.
Forgive my ignorance on this but please tell me what you mean by "using a screw driver, bump the starter relay". I assume this is a way to get it to crank without using the key. Please tell me how to do this as I may be alone when doing the timing so this will be very handy.
Thanks a million for a great write up!
Wil
 

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Bump the "Starter Relay" means with the ignition key in RUN position, lay a screw driver across the 2 big studs there to crank the engine over BUT IMO that's a sure way to burn one up quickly like I did, so a "remote trigger" would certainly be better if you're by yourself OR go old school using a long torque wrench, big drive with a 15/16 socket placed on the crank bolt and turn it by hand, gives you the most "control" in this procedure....it's a bit of of a PITA but works effectively just the same and you won't risk burning up a SR.

Good Luck ~ :thumbup
 

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"Step four. (This is where step one is IMPORTANT, if you don't believe me, go ask Garlic Bronco )
Using a screwdriver, bump the starter relay. When doing so, put a finger over the plug hole. As soon as you feel the big gush of air......."


I have to do this... after pulling my distributor to replace ign control module and pick up coil its starting now but not running right. I can tell the timing is off.
Forgive my ignorance on this but please tell me what you mean by "using a screw driver, bump the starter relay". I assume this is a way to get it to crank without using the key. Please tell me how to do this as I may be alone when doing the timing so this will be very handy.
Thanks a million for a great write up!
Wil
Bump the "Starter Relay" means with the ignition key in RUN position, lay a screw driver across the 2 big studs there to crank the engine over.......
When using this procedure, you don't want the key in the RUN position. Your just bumping the engine over, no need to have the fuel injectors or the coil sending any spark for this.
 
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