Timing Question
Thread Starter
Safety Car
Joined: Aug 2002
Posts: 4,812
Likes: 1
From: New Albany IN
St. Jude Donor '03-'04-'06-'08-'09
Timing Question
I have an odd situation. I have had my '76 for over a year now. Don't drive it much. But when I do it drives fine and runs fine. However, every once in a while I will hear a little "spark knock" or when I get on it I will sometimes hear a slight "popping". Well tonight I decided maybe I should check the timing and see if its off alittle.
Well, to my suprise the timing mark was way way before TDC. I could barely see it up there. I tried turning the distributor as much as I could but I couldn't even get it close, and it ran horrible when I tried.
The previous owner stated that he had the top end rebuilt due to some smoking past the valve guides/seals.
I know I am getting ready to answer my own question, but I noticed that he labeled the wires going to the dist. If you look at the the top of the HEI cover/wire hold-down, there are numbers that I am assuming pertains to the location that each wire goes. I noticed that #1 wire was going to #2.
Is it possible that they put them on wrong and it still runs some-what fine? I know the answer will be to follow all the wires and make sure they are right, but I am still baffeled that it runs so good.
Well, to my suprise the timing mark was way way before TDC. I could barely see it up there. I tried turning the distributor as much as I could but I couldn't even get it close, and it ran horrible when I tried.
The previous owner stated that he had the top end rebuilt due to some smoking past the valve guides/seals.
I know I am getting ready to answer my own question, but I noticed that he labeled the wires going to the dist. If you look at the the top of the HEI cover/wire hold-down, there are numbers that I am assuming pertains to the location that each wire goes. I noticed that #1 wire was going to #2.
Is it possible that they put them on wrong and it still runs some-what fine? I know the answer will be to follow all the wires and make sure they are right, but I am still baffeled that it runs so good.
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
As long as the wires are all inserted clockwise in the correct order, 18436572 then it will be fine.
As far as not being able to find your timing mark, are you positive that you had the inductor clamped on the first plug wire on the front drivers side or were you using #1 off the cap?
Thread Starter
Safety Car
Joined: Aug 2002
Posts: 4,812
Likes: 1
From: New Albany IN
St. Jude Donor '03-'04-'06-'08-'09
Yes, I used front Drivers side plug as spark reference. I will go back and check to see if they are all still in the correct firing order.
Whats the best way to tell if your Harm. Balancer has shifted or slipped?
Whats the best way to tell if your Harm. Balancer has shifted or slipped?
Advanced
Joined: Dec 2005
Posts: 64
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I'm no expert by any means on timing but did you disconnect your vacuum advance and plug it? I know on mine the timing mark changes as soon as I disconnect the vacuum advance and plug it. Just a thought. I have also screwed up and put the distributor thinking I was TDC on the compression stroke but was 180 out.
Last edited by 7t6vette; Oct 2, 2007 at 08:57 AM.
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
Thread Starter
Safety Car
Joined: Aug 2002
Posts: 4,812
Likes: 1
From: New Albany IN
St. Jude Donor '03-'04-'06-'08-'09
UPDATE:
I Noticed that all the plug wires were in the right order but one connector too far counter-clockwise. So I moved them back to where they were supposed to be. I could barely get it to run and the distributor would not turn far enough(vacuum advance hitting intake) to get it to run.
So I am thinking they put the ditributor back in the wrong location. I pulled it out and moved it one tooth clockwise. It runs back to the way it was but now the mark appears to be farther away. So I am guess I went the wrong way.
SIDE NOTE: When I pulled the cap off I was horrified to see that only one bolt was securing the rotor. The other was there, just not attached. The rotor was freely moving up and down and side to side.
Inside the cap you could see some damage on the metal conductors.
So I guess I will be buying new ones tomorrow!
I Noticed that all the plug wires were in the right order but one connector too far counter-clockwise. So I moved them back to where they were supposed to be. I could barely get it to run and the distributor would not turn far enough(vacuum advance hitting intake) to get it to run.
So I am thinking they put the ditributor back in the wrong location. I pulled it out and moved it one tooth clockwise. It runs back to the way it was but now the mark appears to be farther away. So I am guess I went the wrong way.
SIDE NOTE: When I pulled the cap off I was horrified to see that only one bolt was securing the rotor. The other was there, just not attached. The rotor was freely moving up and down and side to side.
Inside the cap you could see some damage on the metal conductors.
So I guess I will be buying new ones tomorrow!
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
UPDATE:
I Noticed that all the plug wires were in the right order but one connector too far counter-clockwise. So I moved them back to where they were supposed to be. I could barely get it to run and the distributor would not turn far enough(vacuum advance hitting intake) to get it to run.
I Noticed that all the plug wires were in the right order but one connector too far counter-clockwise. So I moved them back to where they were supposed to be. I could barely get it to run and the distributor would not turn far enough(vacuum advance hitting intake) to get it to run.
You can simply move all the wires 2 holes CCW.
No need to pull the dist again unless the advance can is in a position where it interferes with setting the timing or the wires are stretched too far.... I think you get my point..
I would probably pull the distributor, set #1 to TDC on the compression stroke and install the distributor, cap and wires the way they were meant to be.
The rotor issue sounds like the source to your original problem
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Thread Starter
Safety Car
Joined: Aug 2002
Posts: 4,812
Likes: 1
From: New Albany IN
St. Jude Donor '03-'04-'06-'08-'09
Thanks! Yes I follow what you are saying.
I guess my goal is to get the timing mark to line up how it is supposed to so I can get an accurate reading. Would the distributor being in the wrong location be the cause of it being to out of place?
Also, is there any easy one-man way of finding top dead center?
I guess my goal is to get the timing mark to line up how it is supposed to so I can get an accurate reading. Would the distributor being in the wrong location be the cause of it being to out of place?
Also, is there any easy one-man way of finding top dead center?
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
I always put my finger over the #1plug hole while someone else bumps the engine but there are other methods and tools you can use such as a piston stop or by removing the drivers side valve cover and watching the valves.... Imo, the finger method is the easiest but it requires two people..
Last edited by Bob Onit; Oct 2, 2007 at 05:40 PM.
Thread Starter
Safety Car
Joined: Aug 2002
Posts: 4,812
Likes: 1
From: New Albany IN
St. Jude Donor '03-'04-'06-'08-'09
SO if there is NO WAY possible that the position of the distibutor shaft can have an effect on the timing mark, then it is good to assume thast the harmonic balancer is out of position?
Instructor
Joined: Dec 2006
Posts: 207
Likes: 0
From: Keller TX
Hi....I'm certainly no expert either but I had a similar problem. Couldn't find my timing mark. Turns out my balancer had slipped. On the attached picture, you can see my old one (orange) compared to the new one.
The timing marks at at the top of each (hard to see) but the key way isn't in the same spot.
A change is a few hours work. Not hard.
Not saying that is your problem...but maybe?
Doug
The timing marks at at the top of each (hard to see) but the key way isn't in the same spot.
A change is a few hours work. Not hard.
Not saying that is your problem...but maybe?
Doug
Advanced
Joined: Dec 2005
Posts: 64
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Not trying to be a smart_ss but unless your sure the balancer has slipped why not confirm your distributor is installed correct before buying a new balancer? Again...I'm no guru but due to distributor problems I've had and repaired here's what I have done. 2 ways:
I bump the iginition until the timing mark on the harmonic balancer is point directly at 0. Sometimes I get it very close but then the next bump passes. I either keep trying or when I get it close I take a socket with a torque wrench and turn the nut center nut on the harmonic balancer to get it right on 0. Once on 0 your rotor should be pointing at the # 1 location of the distributor cap. I have also made a light mark on the distributor base just below the cap where the # 1 spark plug wire should be. Remove the distributor cap (get it out of the way) then bump the ignition until the rotor is pointing at the mark I made. Remove the #1 cylinder spark plug and see if the piston is at TDC. Your harmonic balancer line should be pointing at 0. Just my 2 cents. Hope it helps.
I bump the iginition until the timing mark on the harmonic balancer is point directly at 0. Sometimes I get it very close but then the next bump passes. I either keep trying or when I get it close I take a socket with a torque wrench and turn the nut center nut on the harmonic balancer to get it right on 0. Once on 0 your rotor should be pointing at the # 1 location of the distributor cap. I have also made a light mark on the distributor base just below the cap where the # 1 spark plug wire should be. Remove the distributor cap (get it out of the way) then bump the ignition until the rotor is pointing at the mark I made. Remove the #1 cylinder spark plug and see if the piston is at TDC. Your harmonic balancer line should be pointing at 0. Just my 2 cents. Hope it helps.
Intermediate
Joined: Oct 2002
Posts: 30
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From: Baily CO
The most accurate way to verify all your timing points is
#1 remove all your spark plugs
#2 turn your engine over or bump it with the starter while an assistant plugs #1 cylinder with his finger and stop as soon as compression air is forced out. This is your compression stroke of #1 cylinder.
#3 Next put a socket and extension with a breaker bar or ratchet handle on your crank shaft nut (front bottom pulley)
#4 with a long screw driver carefully insert it into #1 sparkplug hole gently until it touches the top of the piston.
#5 move crankshaft slowly with socket while monitoring screwdriver as it moves up or down into the cylinder. If screwdriver goes down turn crank opposite way till piston is at highest point.
#6 once you have found top dead center, your timing mark should be pointing at TDC on balancer and your distributor rotor should be aligned with #1 wire tower. If not lined up try the above steps again till you are certain you were on TDC of compression stroke #1 cylinder.
#1 remove all your spark plugs
#2 turn your engine over or bump it with the starter while an assistant plugs #1 cylinder with his finger and stop as soon as compression air is forced out. This is your compression stroke of #1 cylinder.
#3 Next put a socket and extension with a breaker bar or ratchet handle on your crank shaft nut (front bottom pulley)
#4 with a long screw driver carefully insert it into #1 sparkplug hole gently until it touches the top of the piston.
#5 move crankshaft slowly with socket while monitoring screwdriver as it moves up or down into the cylinder. If screwdriver goes down turn crank opposite way till piston is at highest point.
#6 once you have found top dead center, your timing mark should be pointing at TDC on balancer and your distributor rotor should be aligned with #1 wire tower. If not lined up try the above steps again till you are certain you were on TDC of compression stroke #1 cylinder.
Thread Starter
Safety Car
Joined: Aug 2002
Posts: 4,812
Likes: 1
From: New Albany IN
St. Jude Donor '03-'04-'06-'08-'09
Thanks for the input guys.
7T6vette, I didn't take you as being a smart azz...you are obsolutely correct. I should check everything first to make sure thats what the problem is or I will still have the same problem even with a new balancer.
It runs fine now, I just can't adjust the timing. I will use the above ideas to try to get it to TDC. Thanks!
7T6vette, I didn't take you as being a smart azz...you are obsolutely correct. I should check everything first to make sure thats what the problem is or I will still have the same problem even with a new balancer.
It runs fine now, I just can't adjust the timing. I will use the above ideas to try to get it to TDC. Thanks!
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
Just pull #1 and when the mark is coming around, put it in 2nd gear and bump the car forward very slowly until the mark is right where you want it....
A little trick I learned from DWncchs (Roger)
Works great ....
