71 LT1 ignition timing
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Joined: Oct 2022
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From: Orland Park Illinois
Not sure what caused the initial timing to be so far off. Bad timing light. I know I was on the correct wire. I was using my truck battery for power. Timing light is about 30 years old. Will check timing tomorrow. Thanks Lars for the info on checking tdc.
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From: At my Bar drinking and wrenching in Lafayette Colorado
Your test shows that the white line is equally spaced between the two black lines, so the balancer has not slipped.
Why are you using a truck battery for the timing light..? Just hook it up to the alternator + terminal and the "GRD" terminal. Set timing to 36 total and see where the initial ends up being.
Why are you using a truck battery for the timing light..? Just hook it up to the alternator + terminal and the "GRD" terminal. Set timing to 36 total and see where the initial ends up being.
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Your test shows that the white line is equally spaced between the two black lines, so the balancer has not slipped.
Why are you using a truck battery for the timing light..? Just hook it up to the alternator + terminal and the "GRD" terminal. Set timing to 36 total and see where the initial ends up being.
Why are you using a truck battery for the timing light..? Just hook it up to the alternator + terminal and the "GRD" terminal. Set timing to 36 total and see where the initial ends up being.
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From: Virginia
Did some posts get deleted?
Anyway, is that the correct timing cover, or is it possible that the timing indicator is what is wrong, not the damper?
Nevermind. Op's damper is fine. Read below for the explanation.
Nevermind. Op's damper is fine. Read below for the explanation.
Last edited by Bikespace; Aug 29, 2023 at 08:07 PM.
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From: At my Bar drinking and wrenching in Lafayette Colorado
You guys are misreading the data....
He has done a TDC check. In doing that, he rotated the crank until the piston hit the piston stop. He then put a black line on the balancer at the "0" mark on the tab. He then rotated the crank the opposite rotation until it hit the piston stop again. He then put another black line on the balancer where the "0" mark on the tab is located. TDC (the line on the balancer - the white line) should then be located exactly halfway between the two black lines. As you can see: It is. He shot the photo after marking the second black line, but he hasn't rotated the crank back to the halfway point, which is right on the white line - the white line is exactly between the two black lines. It's right on.
Everything is good. He just needs to set his timing right with a good timing light.
E-mail me for a copy of my TDC Test paper if you would like to see the process. Steve did it right.
Steve - that is what you did, right...?
Lars
He has done a TDC check. In doing that, he rotated the crank until the piston hit the piston stop. He then put a black line on the balancer at the "0" mark on the tab. He then rotated the crank the opposite rotation until it hit the piston stop again. He then put another black line on the balancer where the "0" mark on the tab is located. TDC (the line on the balancer - the white line) should then be located exactly halfway between the two black lines. As you can see: It is. He shot the photo after marking the second black line, but he hasn't rotated the crank back to the halfway point, which is right on the white line - the white line is exactly between the two black lines. It's right on.
Everything is good. He just needs to set his timing right with a good timing light.
E-mail me for a copy of my TDC Test paper if you would like to see the process. Steve did it right.
Steve - that is what you did, right...?
Lars
Last edited by lars; Aug 29, 2023 at 06:02 PM.
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You guys are misreading the data....
He has done a TDC check. In doing that, he rotated the crank until the piston hit the piston stop. He then put a black line on the balancer at the "0" mark on the tab. He then rotated the crank the opposite rotation until it hit the piston stop again. He then put another black line on the balancer where the "0" mark on the tab is located. TDC (the line on the balancer - the white line) should then be located exactly halfway between the two black lines. As you can see: It is. He shot the photo after marking the second black line, but he hasn't rotated the crank back to the halfway point, which is right on the white line - the white line is exactly between the two black lines. It's right on.
Everything is good. He just needs to set his timing right with a good timing light.
E-mail me for a copy of my TDC Test paper if you would like to see the process. Steve did it right.
Steve - that is what you did, right...?
Lars
He has done a TDC check. In doing that, he rotated the crank until the piston hit the piston stop. He then put a black line on the balancer at the "0" mark on the tab. He then rotated the crank the opposite rotation until it hit the piston stop again. He then put another black line on the balancer where the "0" mark on the tab is located. TDC (the line on the balancer - the white line) should then be located exactly halfway between the two black lines. As you can see: It is. He shot the photo after marking the second black line, but he hasn't rotated the crank back to the halfway point, which is right on the white line - the white line is exactly between the two black lines. It's right on.
Everything is good. He just needs to set his timing right with a good timing light.
E-mail me for a copy of my TDC Test paper if you would like to see the process. Steve did it right.
Steve - that is what you did, right...?
Lars
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Joined: Oct 2022
Posts: 56
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From: Orland Park Illinois
Yes I used Lars procedures for checking TDC. Worked out perfect emailed me the procedures.
Well I got another timing light that was older than mine. Showed the same thing at idle:off the timing scale advance. Changed the number one wire with a new one to see if it would make a difference. Took one inch of movement in the retard clockwise to get 36 full advance timing. I bought this car about 6 months ago. Kind of a work in progress. The car ran but stumbled with out a load. Ran strong when getting on it. I know the timing was a little advance the way it started especially when it was warm. Just hard to believe it would run so good with that advanced. Getting ready to go for a ride.
Well I got another timing light that was older than mine. Showed the same thing at idle:off the timing scale advance. Changed the number one wire with a new one to see if it would make a difference. Took one inch of movement in the retard clockwise to get 36 full advance timing. I bought this car about 6 months ago. Kind of a work in progress. The car ran but stumbled with out a load. Ran strong when getting on it. I know the timing was a little advance the way it started especially when it was warm. Just hard to believe it would run so good with that advanced. Getting ready to go for a ride.
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Yes I used Lars procedures for checking TDC. Worked out perfect emailed me the procedures.
Well I got another timing light that was older than mine. Showed the same thing at idle:off the timing scale advance. Changed the number one wire with a new one to see if it would make a difference. Took one inch of movement in the retard clockwise to get 36 full advance timing. I bought this car about 6 months ago. Kind of a work in progress. The car ran but stumbled with out a load. Ran strong when getting on it. I know the timing was a little advance the way it started especially when it was warm. Just hard to believe it would run so good with that advanced. Getting ready to go for a ride.
Well I got another timing light that was older than mine. Showed the same thing at idle:off the timing scale advance. Changed the number one wire with a new one to see if it would make a difference. Took one inch of movement in the retard clockwise to get 36 full advance timing. I bought this car about 6 months ago. Kind of a work in progress. The car ran but stumbled with out a load. Ran strong when getting on it. I know the timing was a little advance the way it started especially when it was warm. Just hard to believe it would run so good with that advanced. Getting ready to go for a ride.
Are you doing idle timing or something else?
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Joined: Oct 2022
Posts: 56
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From: Orland Park Illinois
Hose disconnect. Initial timing set to 12 BTD and advance the throttle to 3000 roll the timing dial to 36 degrees and timing mark on zero. After. Adjusting timing vacuum dropped to 13” vacuum before adjusting the timing was at 16”. Didn’t drive the car yet just don’t understand how the timing was that far off. Never had a car with the timing so far with out stumbling all over when making this much of a change Seems to run okay where ever you put the distributor. Accel ignition conversion kit with MSD coil. Guess I’ll try to drive it tomorrow. Just don’t want to break anything.
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Hose disconnect. Initial timing set to 12 BTD and advance the throttle to 3000 roll the timing dial to 36 degrees and timing mark on zero. After. Adjusting timing vacuum dropped to 13” vacuum before adjusting the timing was at 16”. Didn’t drive the car yet just don’t understand how the timing was that far off. Never had a car with the timing so far with out stumbling all over when making this much of a change Seems to run okay where ever you put the distributor. Accel ignition conversion kit with MSD coil. Guess I’ll try to drive it tomorrow. Just don’t want to break anything.
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Joined: May 2006
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