potentially dumb points/condenser question
Thread Starter
Racer
Joined: Sep 2002
Posts: 389
Likes: 0
From: san diego ca
potentially dumb points/condenser question
when you replace these, do you have to adjust the new ones before installing?
I tried new sets but couldn't get my '73 to start.
longer story:
about 6-7 months ago I did about 95% of a full tune up - everything but the points/cond. I bought quality Napa parts (cs786/rr175), but couldn't get the car to start with them.
Put the old ones back in, car started/ran fine.
Bought a cheapo set from local O'Reilly store, car wouldn't start again.
Put the old ones back in, car started/ran fine.
So I left the old ones in.
Last week the car started running really crappy, rough, sputtering, lacking power, etc.
I check fuel filter - it's fine.
I checked spark plugs - #8 is not firing.
I read some threads about checking the coil - need to get a new VOM to check resistance.
Could bad points/cond. cause these symtoms? I know they are old (as is the coil).
I know you are supposed to adjust the dwell with new points, but don't you need the car running to do this?
I tried new sets but couldn't get my '73 to start.
longer story:
about 6-7 months ago I did about 95% of a full tune up - everything but the points/cond. I bought quality Napa parts (cs786/rr175), but couldn't get the car to start with them.
Put the old ones back in, car started/ran fine.
Bought a cheapo set from local O'Reilly store, car wouldn't start again.
Put the old ones back in, car started/ran fine.
So I left the old ones in.
Last week the car started running really crappy, rough, sputtering, lacking power, etc.
I check fuel filter - it's fine.
I checked spark plugs - #8 is not firing.
I read some threads about checking the coil - need to get a new VOM to check resistance.
Could bad points/cond. cause these symtoms? I know they are old (as is the coil).
I know you are supposed to adjust the dwell with new points, but don't you need the car running to do this?
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 330
From: Indy Indiana
hard to set gap using a feeler gauge on gm points. they should be set at proper gap when manufactured. but who knows how china has sabotaged us.
so yes, get you a good dwell meter and set the gap based on dwell. set dwell to 30 degrees with the allen wrench.
so yes, get you a good dwell meter and set the gap based on dwell. set dwell to 30 degrees with the allen wrench.
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
If you don't have a set of feeler gauges the old school way was to set them to the thickness of a match book cover. If you're a youngster and don't know what a match book cover is then I can't help you.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
And make 100% sure there is not even a tiny trace of oil on the feeler gauge if that's what you use to set the points. Even a trace will oil the contacts and oil being what it is, it makes a very effective insulator. And no start
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Le Mans Master
Joined: Oct 2010
Posts: 6,929
Likes: 842
From: melbourne florida
2023 C3 of the Year Finalist - Modified
i have never seen a set of points that come out of the box adjusted, its impossible.
adjust them with a feeler gauge to get it close then you can tweak it with a dwell tach with the car running. if it calls for 30 degrees adjust to 15 thousands 32 degrees 16 thousands. its not rocket science.
the rubbing block on the point set should be sitting on the high point of the lobe, at that point you adjust the hex head to get your setting.
adjust them with a feeler gauge to get it close then you can tweak it with a dwell tach with the car running. if it calls for 30 degrees adjust to 15 thousands 32 degrees 16 thousands. its not rocket science.
the rubbing block on the point set should be sitting on the high point of the lobe, at that point you adjust the hex head to get your setting.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 98
From: Ontario
You realize that that approach dates you but it does work. I think I just dated myself! But I do have a dwell tachometer as backup.
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
I have had that problem... from 2010:
I can't figure out why the car would not start with a brand new out of the box set of points. I put them in/ took them out twice. Both times car started with old points but not new points. The parts are nearly identical (same Echlin part #). I have done stupid stuff in the past like leave out the rotor. Today I forgot to reattach the ignition wire to the coil (so no cranking first try). But I swapped in/out the new points twice and checked everything. Car ran with the old set but would not start with the new set. Not even a hint of running, just cranking.
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Drifting
Joined: Sep 2010
Posts: 1,412
Likes: 50
From: Laguna Niguel California
Just because points and condenser are new doesn't mean they are good. Over the years I have bought components that were grounded out when new. Try another set from a quality source.
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
With the points mounted in the dist but with the positive wire disconnected, when the points are open you should be able to connect an ohmmeter one wire to the connection where the positive wire goes and one to earth and get an open circuit reading, when the points are closed you should get a low resistance reading. Or, if you have everything connected up and the points are closed with the key on and the motor not running the ign coil should start to get warm, or you can pull the wire that goes from the dist to the coil terminal and if you touch the connection together there should be a small spark there.
Thread Starter
Racer
Joined: Sep 2002
Posts: 389
Likes: 0
From: san diego ca
Lots of good info here, thanks all. I don't have a dwell meter, but can start looking for one. I was expecting the factory settings to be close enough to start with.
I did read about suggestion of filing the contacts every so slightly...would go along with cleaning and ensuring no oil.
I'll start by going back to Napa and getting the eichlin set again.
curious: why use the old condenser?
I did read about suggestion of filing the contacts every so slightly...would go along with cleaning and ensuring no oil.
I'll start by going back to Napa and getting the eichlin set again.
curious: why use the old condenser?
