Distributor adjustment
Thread Starter
Pro
Joined: Nov 2005
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From: Foxboro Ma
Distributor adjustment
There may be a simple solution but I have not yet figured it out.
My engine (Single 4 barrel, single points)currently is running very well and starts very easy with the distributor in its current location. My problem is that I was going to see how everything would line up to put the radio shielding on and to my surprise I could not attach the support bracket that holds the coil and then install the coil because the vacuum mechanics are in the way. I have looked at pictures and other car with the shielding installed and what is confusing to me is they appear to have the vacuum mechanic protruding out under the shield in about the same place where mine is situated but obviously not the case.
My car is still away for the winter and I would like to understand what I am missing before spring if possible....so that gives me about 2-3 months...
Thanks in advance for any information...
My engine (Single 4 barrel, single points)currently is running very well and starts very easy with the distributor in its current location. My problem is that I was going to see how everything would line up to put the radio shielding on and to my surprise I could not attach the support bracket that holds the coil and then install the coil because the vacuum mechanics are in the way. I have looked at pictures and other car with the shielding installed and what is confusing to me is they appear to have the vacuum mechanic protruding out under the shield in about the same place where mine is situated but obviously not the case.
My car is still away for the winter and I would like to understand what I am missing before spring if possible....so that gives me about 2-3 months...
Thanks in advance for any information...
Melting Slicks
Joined: Oct 2004
Posts: 3,345
Likes: 87
From: Northern MN
St. Jude Donor '13-'14-'15-'16-'17
There may be a simple solution but I have not yet figured it out.
My engine (Single 4 barrel, single points)currently is running very well and starts very easy with the distributor in its current location. My problem is that I was going to see how everything would line up to put the radio shielding on and to my surprise I could not attach the support bracket that holds the coil and then install the coil because the vacuum mechanics are in the way. I have looked at pictures and other car with the shielding installed and what is confusing to me is they appear to have the vacuum mechanic protruding out under the shield in about the same place where mine is situated but obviously not the case.
My car is still away for the winter and I would like to understand what I am missing before spring if possible....so that gives me about 2-3 months...
Thanks in advance for any information...
My engine (Single 4 barrel, single points)currently is running very well and starts very easy with the distributor in its current location. My problem is that I was going to see how everything would line up to put the radio shielding on and to my surprise I could not attach the support bracket that holds the coil and then install the coil because the vacuum mechanics are in the way. I have looked at pictures and other car with the shielding installed and what is confusing to me is they appear to have the vacuum mechanic protruding out under the shield in about the same place where mine is situated but obviously not the case.
My car is still away for the winter and I would like to understand what I am missing before spring if possible....so that gives me about 2-3 months...
Thanks in advance for any information...
Where does the window for setting the points sit?? Should be facing the back of the carb. If not, sounds like your unit is a cog off on the cam gear. If it is the timing is set correctly and you'll have to look at the vacuum can or the shielding. JMT
Steve
Safety Car
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From: St. Joseph Mo
Safety Car
Joined: Feb 2003
Posts: 4,068
Likes: 27
From: St. Joseph Mo
There may be a simple solution but I have not yet figured it out.
My engine (Single 4 barrel, single points)currently is running very well and starts very easy with the distributor in its current location. My problem is that I was going to see how everything would line up to put the radio shielding on and to my surprise I could not attach the support bracket that holds the coil and then install the coil because the vacuum mechanics are in the way. I have looked at pictures and other car with the shielding installed and what is confusing to me is they appear to have the vacuum mechanic protruding out under the shield in about the same place where mine is situated but obviously not the case.
My car is still away for the winter and I would like to understand what I am missing before spring if possible....so that gives me about 2-3 months...
Thanks in advance for any information...
My engine (Single 4 barrel, single points)currently is running very well and starts very easy with the distributor in its current location. My problem is that I was going to see how everything would line up to put the radio shielding on and to my surprise I could not attach the support bracket that holds the coil and then install the coil because the vacuum mechanics are in the way. I have looked at pictures and other car with the shielding installed and what is confusing to me is they appear to have the vacuum mechanic protruding out under the shield in about the same place where mine is situated but obviously not the case.
My car is still away for the winter and I would like to understand what I am missing before spring if possible....so that gives me about 2-3 months...
Thanks in advance for any information...
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
If your distributor drive gear is on the shaft correctly ("dimple" on the gear pointing in the same direction as the rotor tip) and the distributor is installed correctly (not a tooth or two off in either direction), the housing and vacuum advance should be oriented and the wires indexed in the cap as shown in the photo below with the timing set to specs. The photo is not a Corvette, but the orientation shown is correct.
If the vacuum advance hits the plug wire support/coil at one extreme or the #8 intake runner on the manifold at the other extreme while trying to set the timing, one or more of the items in the first paragraph above is not correctly oriented.
If the vacuum advance hits the plug wire support/coil at one extreme or the #8 intake runner on the manifold at the other extreme while trying to set the timing, one or more of the items in the first paragraph above is not correctly oriented.
Thread Starter
Pro
Joined: Nov 2005
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From: Foxboro Ma
The manner in which mine setup currently appears is the same as the picture John Z provided. The coil near the number 7 wire. The problem I have is when I try to install the bracket the holds the coil near the number 8 wire and then install the coil the vacuum assembly is in the way and does not allow me to locate the coil near the number 8. I am not sure if I could use tie wraps or other method of attaching the coil so it fits under the shield or not.
I appreciate all of the information. I will have to pull the distributor and check to see if the dimples align as described...
Thanks, John
I appreciate all of the information. I will have to pull the distributor and check to see if the dimples align as described...
Thanks, John
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
If I read this right, your coil is presently in the wrong location and you want to reclocate it on the right rear of the engine? Sounds like all you need to do is pull the distributor up and rotate the rotor counter clockwise one tooth notch on the cam and drop it back in and retime it. This will orient your vacuum can more toward the carb and out of the way of the relocated coil bracket. I'm sure you know the correct coil bracket for mid-years is not as John shows in the photo.
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Team Owner
Joined: Aug 1999
Posts: 30,995
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From: Ontario
Paul:
In your top pic I see a round head screw holding the vac can to the dist housing. You may want to make certain the points plate clears it. It should be a pan head screw.
Thanks! I'll check that in the spring.
In your top pic I see a round head screw holding the vac can to the dist housing. You may want to make certain the points plate clears it. It should be a pan head screw.
Thanks! I'll check that in the spring.
Thread Starter
Pro
Joined: Nov 2005
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From: Foxboro Ma
MikeM,
Thanks, you make it sound pretty simple. I was reluctant to rotate the distributor because I was/am not sure how everything will line up meaning the firing order etc...I thought if I pull the distributor up and rotate it CC a bit it would mess everything up meaning, 8 would be 1 and 1 would be 2 etc...is you look at JohnZ's picture. Am I looking at this correctly???
Thanks, John
Thanks, you make it sound pretty simple. I was reluctant to rotate the distributor because I was/am not sure how everything will line up meaning the firing order etc...I thought if I pull the distributor up and rotate it CC a bit it would mess everything up meaning, 8 would be 1 and 1 would be 2 etc...is you look at JohnZ's picture. Am I looking at this correctly???
Thanks, John
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
You're looking at it correctly if I am. Just slowly pull up on the distributor while you put a little pressure of the rotor, counter clockwise. You may have to wiggle the distributor housing back and forth. Go slow. You will feel the teeth on the gears dis-engage or jump to the next tooth. Just drop the distributor back down in the hole. You will probably have to bump the starter motor to get the oil pump to seat in the distributor and that'll let the distributor drop all the way down. No need to rewire the cap or change anything else.
Drifting
Joined: Oct 2004
Posts: 1,255
Likes: 7
From: Coralville Iowa
I vote 1 tooth off.
Usually with 1 tooth you won't even have to relocate the oil pump drive. Pull it up, rotate 1 tooth, drop it back easy and work it into the top of the pump. Check for clearance on the shielding. Reset the timing and you're done.
Needless to say, you can drop your distributor in at any point (that the vacuum canister clears) as long as you have #1 cylinder set on the balancer and you move around your plug wires on the cap.
We did that just for fun in high school on a mallory dual point mechanical advance.
Rotated it 60 degrees and changed the plug wires.
Sure confused a lot of car guys!
Usually with 1 tooth you won't even have to relocate the oil pump drive. Pull it up, rotate 1 tooth, drop it back easy and work it into the top of the pump. Check for clearance on the shielding. Reset the timing and you're done.
Needless to say, you can drop your distributor in at any point (that the vacuum canister clears) as long as you have #1 cylinder set on the balancer and you move around your plug wires on the cap.
We did that just for fun in high school on a mallory dual point mechanical advance.
Rotated it 60 degrees and changed the plug wires.
Sure confused a lot of car guys!
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
You're looking at it correctly if I am. Just slowly pull up on the distributor while you put a little pressure of the rotor, counter clockwise. You may have to wiggle the distributor housing back and forth. Go slow. You will feel the teeth on the gears dis-engage or jump to the next tooth. Just drop the distributor back down in the hole. You will probably have to bump the starter motor to get the oil pump to seat in the distributor and that'll let the distributor drop all the way down. No need to rewire the cap or change anything else.
If you did it as described and it is correctly timed, your distributor will look like John's picture and your coil/shielding should fit. If you can't time it without interference with the relocated coil or the intake, you may have to totate the gear on the distributor 180* to make it line up.
If you did it as described and it is correctly timed, your distributor will look like John's picture and your coil/shielding should fit. If you can't time it without interference with the relocated coil or the intake, you may have to totate the gear on the distributor 180* to make it line up.
Team Owner
Joined: Aug 1999
Posts: 30,995
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From: Ontario
If you look at this pic and compare it to my other above you will see the consequences of "one-tooth-off". The one below was taken at *8BTDC. I was attempting to get 10*BTDC but the vacuum canister was butting up against the intake runner. My first/above pic shows timing at 10*BTDC after a one tooth shift. The tip of the canister is pointing at the valve cover bolt, my rough-and-ready, starting reference point before fine-tuning. Much more room to make that so.
Last edited by Paul L; Jan 31, 2008 at 05:14 PM.
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From: Foxboro Ma
Paul,
Thanks for the additional picture to show the difference.
Sorry for asking what may be a simple question but...when I lift the distributor up and hold the rotor in the same location as I turn the distributor enough so it moves one tooth and then slide it back down won't this through off my timing a lot ??? Will I still be able to set the time although I moved the original setting that are right now perfect ?
Thanks in advance for any help...
John
Thanks for the additional picture to show the difference.
Sorry for asking what may be a simple question but...when I lift the distributor up and hold the rotor in the same location as I turn the distributor enough so it moves one tooth and then slide it back down won't this through off my timing a lot ??? Will I still be able to set the time although I moved the original setting that are right now perfect ?
Thanks in advance for any help...
John
Melting Slicks
Joined: Oct 2004
Posts: 3,345
Likes: 87
From: Northern MN
St. Jude Donor '13-'14-'15-'16-'17
Paul,
Thanks for the additional picture to show the difference.
Sorry for asking what may be a simple question but...when I lift the distributor up and hold the rotor in the same location as I turn the distributor enough so it moves one tooth and then slide it back down won't this through off my timing a lot ??? Will I still be able to set the time although I moved the original setting that are right now perfect ?
Thanks in advance for any help...
John
Thanks for the additional picture to show the difference.
Sorry for asking what may be a simple question but...when I lift the distributor up and hold the rotor in the same location as I turn the distributor enough so it moves one tooth and then slide it back down won't this through off my timing a lot ??? Will I still be able to set the time although I moved the original setting that are right now perfect ?
Thanks in advance for any help...
John
John,
When you lift the distributor you turn the rotor, not the distributor body. The gear that you are trying to change is attached to the end of the shaft on which the rotor turns. Yes, after you move the timing one cog you will be able to time the engine.
Steve
Team Owner
Joined: Aug 1999
Posts: 30,995
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From: Ontario
Those pics are from three years ago and my memory may not serve me well in remembering the thread, but I believe one tooth off is equal to 13*. I had a double whammy on my hands then, the dimple was 180* off (fix #1) and I re-installed one tooth off (fix #2). That was an interesting and frustrating Saturday afternoon before the Forum straightened me out. Live and learn.
Melting Slicks
Joined: Oct 2004
Posts: 3,345
Likes: 87
From: Northern MN
St. Jude Donor '13-'14-'15-'16-'17
Those pics are from three years ago and my memory may not serve me well in remembering the thread, but I believe one tooth off is equal to 13*. I had a double whammy on my hands then, the dimple was 180* off (fix #1) and I re-installed one tooth off (fix #2). That was an interesting and frustrating Saturday afternoon before the Forum straightened me out. Live and learn.
Paul,
Was that due to the odd number of gear teeth? If the dimple is 180 degrees off and there are an equal number of teeth, it shouldn't make any difference. Right???
Steve
