235 no spark... Coil? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Rednek13x · 03-12-2013, 10:31 PM

Trucks got no spark, just started going through and testing the system. has not ran since 2002, and never since i owned it.

I tested the ignition coil primary winding with an ohms reading of 2.1
the secondary had a reading of 10.5K ohms

Both of them seems to check out good...

I then did a dynamic volts test on the primary winding and only got like 1.5 volts... I know it should be 100V or more to run..?

Is this right or am i lost?

If this is right, now maybe points? I dont know.... whats next? Just wanted to make sure my coil is good first. Oh and also i ran a jumper from the + on the battery to the + on the coil to bypass everything...

mr48chev · 03-12-2013, 11:57 PM

You aren't going to get a spark out of the coil unless you crank the engine so that the points will open and close.

Did you check the point to see if they are indeed opening and closing and have about a .016 gap when the rubbing block on the point arm is on one of the high points of the distributor cam?
Is the screw that holds the condensor tight.
ARE the piece on the points and the the wire end on the condenser wire in the right spot so they won't ground out?

That's just a few things that I have seen over the years.

Rednek13x · 03-13-2013, 10:37 AM

I will check all that out later today, off to the auto show right now. And i indeed turn the motor over when checking for spark.

But as far as i can tell my coil is good?? Now to check points next thing down the line..

Speedbumpauto · 03-13-2013, 11:46 AM

99% of the time, that problem is breaker points corroded or out of adjustment.

OrrieG · 03-13-2013, 03:55 PM

Get new points and condenser. I used to see a lot of rigs that the points had been changed but still had the old condenser. Like Mr48 said if you don't pay attention when tightening the point/condenser screw the wire fitting can rotate and ground on the base plate.

NEWFISHER · 03-13-2013, 04:39 PM

Quote:

Originally Posted by OrrieG

Get new points and condenser. I used to see a lot of rigs that the points had been changed but still had the old condenser. Like Mr48 said if you don't pay attention when tightening the point/condenser screw the wire fitting can rotate and ground on the base plate.

And keep a set in the glove box too!!!!!!

mr48chev · 03-13-2013, 05:27 PM

Two things that I have run into on engines that have a no spark or no start condition are that the person who changed the points either gaped the points with the rubbing block against the flat of the distributor cam or they set the point gap the same as the spark plug gap.

The other thing I've seen a number of times on the "we tuned it up and it won't run" cars is that they put a wire back in the wrong place in the distributor either grounding the ignition out or the wire is on the wrong side of the insulator and isn't making contact with the points or the screw that the coil secondary wire fastens to.

Rednek13x · 03-13-2013, 11:18 PM

Tried filing the points, still nothing. Going to get new points and condenser tomorrow. Will get back to yall how it works.

03-12-2013, 10:31 PM	#1
Rednek13x Registered User Join Date: Feb 2011 Location: Clear Lake, MN Posts: 329	235 no spark... Coil? Trucks got no spark, just started going through and testing the system. has not ran since 2002, and never since i owned it. I tested the ignition coil primary winding with an ohms reading of 2.1 the secondary had a reading of 10.5K ohms Both of them seems to check out good... I then did a dynamic volts test on the primary winding and only got like 1.5 volts... I know it should be 100V or more to run..? Is this right or am i lost? If this is right, now maybe points? I dont know.... whats next? Just wanted to make sure my coil is good first. Oh and also i ran a jumper from the + on the battery to the + on the coil to bypass everything...

03-12-2013, 11:57 PM	#2
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,349	Re: 235 no spark... Coil? You aren't going to get a spark out of the coil unless you crank the engine so that the points will open and close. Did you check the point to see if they are indeed opening and closing and have about a .016 gap when the rubbing block on the point arm is on one of the high points of the distributor cam? Is the screw that holds the condensor tight. ARE the piece on the points and the the wire end on the condenser wire in the right spot so they won't ground out? That's just a few things that I have seen over the years. __________________ Founding member of the too many projects, too little time and money club. My ongoing truck projects: 48 Chev 3100 that will run a 292 Six. 71 GMC 2500 that is getting a Cad 500 transplant. 77 C 30 dualie, 454, 4 speed with a 10 foot flatbed and hoist. It does the heavy work and hauls the projects around.

03-13-2013, 10:37 AM	#3
Rednek13x Registered User Join Date: Feb 2011 Location: Clear Lake, MN Posts: 329	Re: 235 no spark... Coil? I will check all that out later today, off to the auto show right now. And i indeed turn the motor over when checking for spark. But as far as i can tell my coil is good?? Now to check points next thing down the line..

03-13-2013, 11:46 AM	#4
Speedbumpauto Registered User Join Date: Aug 2011 Location: Tucson, AZ Posts: 917	Re: 235 no spark... Coil? 99% of the time, that problem is breaker points corroded or out of adjustment.

03-13-2013, 03:55 PM	#5
OrrieG Registered User Join Date: Jun 2006 Location: Idaho Posts: 8,800	Re: 235 no spark... Coil? Get new points and condenser. I used to see a lot of rigs that the points had been changed but still had the old condenser. Like Mr48 said if you don't pay attention when tightening the point/condenser screw the wire fitting can rotate and ground on the base plate. __________________ 1959 Chevy Short Fleetside w/ 74 4WD drive train (current project) OrrieG Build Thread 1964 Chevelle Malibu w/ 355-350TH (daily driver) Helpful AD and TF Manual Site Old Car Manual Project

03-13-2013, 05:27 PM	#7
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,349	Re: 235 no spark... Coil? Two things that I have run into on engines that have a no spark or no start condition are that the person who changed the points either gaped the points with the rubbing block against the flat of the distributor cam or they set the point gap the same as the spark plug gap. The other thing I've seen a number of times on the "we tuned it up and it won't run" cars is that they put a wire back in the wrong place in the distributor either grounding the ignition out or the wire is on the wrong side of the insulator and isn't making contact with the points or the screw that the coil secondary wire fastens to. __________________ Founding member of the too many projects, too little time and money club. My ongoing truck projects: 48 Chev 3100 that will run a 292 Six. 71 GMC 2500 that is getting a Cad 500 transplant. 77 C 30 dualie, 454, 4 speed with a 10 foot flatbed and hoist. It does the heavy work and hauls the projects around.

03-13-2013, 11:18 PM	#8
Rednek13x Registered User Join Date: Feb 2011 Location: Clear Lake, MN Posts: 329	Re: 235 no spark... Coil? Tried filing the points, still nothing. Going to get new points and condenser tomorrow. Will get back to yall how it works.



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