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> Dwell - cannot get larger than 39, '74 2.0 - Barn Find
ctc911ctc
post Sep 14 2018, 03:41 PM
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Hi,

Have been spending a great amount of time on timing.

Bought new everything (points, wires, coil, etc).

set the gap to .016 as per the manual and then the dwell came in at 25.

closed the gap more and cannot get the dwell above 40 (aiming at 45). Right now it is at 39.

Question: what would you chase first?

Points? (perhaps they are not engineered correctly) (they are not Bosch)
Dwell Meter ( I have 2 of the same manufacturer - I know, I know.....)
Ignition Cam? (car has 20K on it, should be ok)
Ignore the last 6-8 dwell points and go to the next thing (close enough)

Thank
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TheCabinetmaker
post Sep 14 2018, 04:11 PM
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Do you have the meter set to 4cyl?
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Spoke
post Sep 14 2018, 07:30 PM
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My comment won't help you set the points correctly. I had trouble with points many years ago and bought Pertronix inductive pickup and never looked back. Just set the timing and forget about it. Points and condenser are so archaic in today's automotive world.
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Jeff Hail
post Sep 14 2018, 08:53 PM
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Did you disconnect and plug the vacuum line?

Krusty speaks posthumously from the grave! Roll with it.

The CORRECT way to hook up the dwell meter is the positive lead to the point side of the coil (terminal "1" or (-)), and the ground lead to a good engine ground.

This kinda crap goes into the archives, and some newbie spends a year of his life trying to get his car started, trying every wrong trail until he gets to my post, if he lives that long.

When you get the dwell set, shut it off check to see that the rotor is pretty much centered on the line for cylinder #1 when the engine is at TDC #1. Fix that if it's wrong, then start the car, warm it up, and set the timing at the RED, BLACK, or unpainted full advance mark on the fan, 2800 RPM.. BOTH HOSES OFF. The mark is one fan blade BEFORE the first wide fan support. It MAY not be marked on both sides of the fan, and you mAY have to lay over the trunk lid and get your head right down over the access hole to see the mark. Report back.

The rest of you hang your heads in shame.

If you had any questions about how I got to be Cap'n Krusty, read your 17 answers to the original question.

The Cap'n, goin' easy on you
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ctc911ctc
post Sep 15 2018, 05:13 PM
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Jeff,

Funny you sent this, I read this thread prior to working on the timing.

As a EE I understand BACK-EMF and how the points/coil work. The dwell is set to the switched side of the coil or (-).

Seems to run OK, will try and set the points tighter than .010 and see if the dwell come up.

Thank you for the CapNKrusty reference.

C




QUOTE(Jeff Hail @ Sep 14 2018, 08:53 PM) *

Did you disconnect and plug the vacuum line?

Krusty speaks posthumously from the grave! Roll with it.

The CORRECT way to hook up the dwell meter is the positive lead to the point side of the coil (terminal "1" or (-)), and the ground lead to a good engine ground.

This kinda crap goes into the archives, and some newbie spends a year of his life trying to get his car started, trying every wrong trail until he gets to my post, if he lives that long.

When you get the dwell set, shut it off check to see that the rotor is pretty much centered on the line for cylinder #1 when the engine is at TDC #1. Fix that if it's wrong, then start the car, warm it up, and set the timing at the RED, BLACK, or unpainted full advance mark on the fan, 2800 RPM.. BOTH HOSES OFF. The mark is one fan blade BEFORE the first wide fan support. It MAY not be marked on both sides of the fan, and you mAY have to lay over the trunk lid and get your head right down over the access hole to see the mark. Report back.

The rest of you hang your heads in shame.

If you had any questions about how I got to be Cap'n Krusty, read your 17 answers to the original question.

The Cap'n, goin' easy on you

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ctc911ctc
post Sep 15 2018, 05:14 PM
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Thanks - will pursue the points - going for 100% factory rebuild. Chasing a dream to be sure...........

Thanks again,
C



QUOTE(Spoke @ Sep 14 2018, 07:30 PM) *

My comment won't help you set the points correctly. I had trouble with points many years ago and bought Pertronix inductive pickup and never looked back. Just set the timing and forget about it. Points and condenser are so archaic in today's automotive world.

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r_towle
post Sep 16 2018, 09:06 AM
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Pull the distributor, set the points on the bench?
Might give you a better angle of attack?

It’s a 4 lobe cam in the distributor.
Get close to what you think is TDC, with the points open, then turn the distributor back and forth while watching the gap in the points.you may be setting them slightly off.

16 gets you home, but it’s rarely 16 in my experience.
It’s usually less.
I remember using a matchbook cover to set points (to get home) after a roadside tune while scraping carbon off the points with a knife, then setting them with a matchbook cover, in the dark....after a long night.

You can get this, drop down a gauge.
Remember, each car is different, the gauge gets you close, the dwell meter is the true setting.
Car won’t run right if the dwell is off.
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