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Am I missing something easy... timing question

tbone722

New Member
Joined
May 25, 2009
Messages
10
I have recently redone most all of the ignition system including new box, coil, larger cap and wires. Timing was initially set at 12 after stabbing at TDC. Started trying to jet down the 1406 now that I have an AFR gauge installed. After the first round things were running as good as they ever have, but still rich. Went back to add timing using a vacuum gauge. When I started it appeared to still at 12. Advancing distributer added and steadied the vacuum significantly (jumping a little at 14-15 to very smooth at 17-18. When I looked down timing was at 30. Tried to go back down, but below 18 it was making what might be a pinging sound. I removed the vacuum advance before starting and that is where I connected the vacuum gauge (manifold vacuum {drivers side of 1406}).
 

B RON CO

Contributor
Bronco Guru
Joined
Jun 29, 2016
Messages
2,484
Loc.
Statesville, NC
Hi, most of our engines do fine at @12* BTDC.
If you are using it the ported vacuum source, the way Ford did,you should not have vacuum at the hose for the distributor at idle.
Personally, it would go back to 12*, and use ported vacuum, on the right side of an AFB carb.
Can you post the air / fuel numbers at idle, cruise, and power?
Good luck
I forgot to mention that the ignition should be all set, then dial in the carb mixture screws and idle speed.
 
Last edited:

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,872
total timing should be around 30 degrees at 3,000 rpm total centrifical and vacuum advance. maybe 10-12 degrees at idle with vacuum off and plugged. factory was 6 degrees advanced at idle using venturi vacuum which is no vacuum at idle. sure your using the right timing port on the carb? if you don't have a timing light borrow one at the auto parts. use your vacuum gauge to adjust mixture screws to highest steady vacuum at idle. you might buy a timing tape for your crankshaft damper they are sold by the diameter if your damper.
 
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T

tbone722

New Member
Joined
May 25, 2009
Messages
10
I think I may have a cylinder down and it's unrelated to the change in timing. I have a light and had originally set it at 12. I was just going back to see if a little more timing helped. I feel like y'all have confirmed it shouldn't need much more than where it was and certainly not 20+. I should have been able to advance it a little and brought it back without anything major changing??? I never removed the distributor. I took out the #1 plug and with the dizzy pointed at one I still seem to be at TDC. I guess I was afraid maybe it had jumped time.
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,872
start the engine take a bottle of water like a windex bottle and squirt it at the exhaust port on port at a time look for the port that doesnt sizzle off like the others that's you dead hole. check the plug and the wire maybe swap wires from a different cylinder and see if the problem goes with the wire.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,619
I feel like y'all have confirmed it shouldn't need much more than where it was and certainly not 20+.

At least not at idle with no vacuum advance. Just make sure your idle is below 1,000 rpm for testing or you might be seeing some mechanical advance too.
It's not supposed to start that low normally, but without knowing what distributor, how it was set up at the factory, or what bits were installed, it's hard to say where yours will start to gain except for what you found with the timing light initially.

I should have been able to advance it a little and brought it back without anything major changing???

Yes, definitely.
Unless something is loose, or otherwise deteriorating, changing timing with the distributor is repeatable and returnable without worry about things changing.

I never removed the distributor. I took out the #1 plug and with the dizzy pointed at one I still seem to be at TDC.

So you are saying you verified your distributor is installed correctly and has not changed because the #1 piston is at the top of it's stroke when the rotor is pointed at the #1 plug wire terminal?
You can't really tell the degrees accurately that way. You can get close, and you can verify that the distributor is installed correctly, but you can't tell that you're exactly at a certain degree without the help of the light.
Maybe I'm not sure what you're saying here?

No matter though, since you did not remove the distributor then nothing changed other than what you renewed yourself outside of the distributor.
Just to be sure though, you know the correct location of the #1 cylinder on Fords, and that the distributor rotates counter-clockwise when the crank is rotating clockwise, and all that stuff. Correct?
Just checking. Sounds like you're on top of it, but wanted to make sure since this stuff rears up and bites us in the butt often enough.

I guess I was afraid maybe it had jumped time.

Anything is possible, but jumping time is actually pretty rare and only happens when the timing chain and/or gears are severely worn. Or defective...
Are they original? How many miles?

Remember too that jumping time, or whatever might change, does not effect your timing light. If you're reading 12 degrees, then that's what you have. The light reacts to the actual spark, and the timing marks are aligned with the piston. And that's it...
So even if the distributor has skipped a tooth, or the timing chain has jumped and now the camshaft is out of time (cam timing, NOT ignition timing) if you turn the distributor until the timing marks line up like you want, then your ignition timing is what it says it is with the light.

Paul
 

broncogt

Jr. Member
Joined
Mar 1, 2010
Messages
93
Check your harmonic balancer.

If you have a bunch of cracked rubber the outside can spin. You will not have any idea where your timing really is. This happened to me.
 

Rustytruck

Bronco Guru
Joined
Feb 24, 2002
Messages
10,872
To check your timing chain take the cap off your distributor rotate the engine to top dead center. then rotate the engine backwards just until the rotor in your distributor starts to move and stop. now look at your timing marks. how far are you from top dead center. if you 15-20 degrees your pretty much at the wear point. you can estimate by looking at the timing marks on the balancer and comparing to how far you have moved. much easier if you have a timing tape.
 
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