Trouble getting 12 volts
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I'm sorry you're still having trouble CanOfBeans, but why start a completely new thread when you have literally three months worth of questions-n-answers going on over there?
You've been discussing a no-start issue for awhile now in the other thread and I see no reason to make us start all over again with all the same questions that may already have been asked. With no quick access to some of the clues and things you've already tried.
Just narrowing it down to a voltage thing does not justify a new discussion when it's really still the same no-start problem.
And yes, the 10v seems low, but it's not out of line for a reading you get during cranking. Where are you measuring the voltage, and have you tested your meter on other known good older vehicles to see how they react? Won't likely be the same if you're testing a Honda with a 4-cyl engine of course, but any older V8 should give you the desired voltage readings during START.
Generally though, if your engine is being turned over normally by the starter then you have sufficient voltage to create a spark.
You say you're not sure if it's turning over quickly or not, but if you know the normal sound of a starter motor spinning an engine, you can tell if it's slower or not.
Did you measure the ohms on the distributor's Purple and Green (or Orange?) wires? Should fall well between 400 and 800 ohms.
You can test the relative health of a coil by itself not only with ohms, but by disconnecting it from the electrical system and using a jumper wire to apply 12v to the positive side and another jumper wire to manually open and close (ground and release) the negative side.
With the coil wire lying near grounded metal, you should get a big fat healthy spark jumping from the coil wire each time you remove the ground wire.
If it does this consistently, the coil is fine.
Paul
You've been discussing a no-start issue for awhile now in the other thread and I see no reason to make us start all over again with all the same questions that may already have been asked. With no quick access to some of the clues and things you've already tried.
Just narrowing it down to a voltage thing does not justify a new discussion when it's really still the same no-start problem.
And yes, the 10v seems low, but it's not out of line for a reading you get during cranking. Where are you measuring the voltage, and have you tested your meter on other known good older vehicles to see how they react? Won't likely be the same if you're testing a Honda with a 4-cyl engine of course, but any older V8 should give you the desired voltage readings during START.
Generally though, if your engine is being turned over normally by the starter then you have sufficient voltage to create a spark.
You say you're not sure if it's turning over quickly or not, but if you know the normal sound of a starter motor spinning an engine, you can tell if it's slower or not.
Did you measure the ohms on the distributor's Purple and Green (or Orange?) wires? Should fall well between 400 and 800 ohms.
You can test the relative health of a coil by itself not only with ohms, but by disconnecting it from the electrical system and using a jumper wire to apply 12v to the positive side and another jumper wire to manually open and close (ground and release) the negative side.
With the coil wire lying near grounded metal, you should get a big fat healthy spark jumping from the coil wire each time you remove the ground wire.
If it does this consistently, the coil is fine.
Paul
I measured the voltage with the multimeter through the negative and positive battery posts with my truck being 10.3 during cranking and my 2007 v8 explorer being 11.8
I measured the ohms between the green and purple and got 8.66 kiloohm which is way out of the ballpark from 400 to 800 ohms. Measured the orange and purple and got even more than that. It is a brand new ds2 harness so maybe my multimeter is acting funky
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And just what were the circumstances under which it first refused to start? Did you do some work on it, or were you driving it and it died? Or had it been sitting for decades?
I'm sure these must have been asked in your other thread, but I don't remember even though the last few questions were as recently as this weekend if I remember?
Good luck.
Paul
I'm sure these must have been asked in your other thread, but I don't remember even though the last few questions were as recently as this weekend if I remember?
Good luck.
Paul
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So then it has to be spark if fuel won't do anything. if you have fuel and good spark any engine should do something when you crank it .
I assume you have the stock durashart ignition ? I suspect the coil or the ecm. I've never tried to test either I just replace them.
I would think 10v would be enough to fire things up but I'm not sure of that. Mopar electronic ignition runs on 8V . if you want to eliminate that possibility you could run a test jump wire to the input side of the coil from the battery or solenoid.
I assume you have the stock durashart ignition ? I suspect the coil or the ecm. I've never tried to test either I just replace them.
I would think 10v would be enough to fire things up but I'm not sure of that. Mopar electronic ignition runs on 8V . if you want to eliminate that possibility you could run a test jump wire to the input side of the coil from the battery or solenoid.
and an hei distributor but both are the same problem. From what I've been hearing 10v should be enough but my engine just wants to be stubborn I must be missing a ground somewhere or something. Even with a wire straight from the + post of battery it was still the same problem
Lead Driver
Joined: Jul 2017
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From: San Jose, CA
Your logic is totally sound, and it's not like you're going to be put on Double-Secret Probation or anything. But still, just like has basically already happened, the questions and possible solutions will run the gamut from battery, charging system, cables and wiring, age of the starter, checking compression, are you sure it's a spark thing, and all that happy crap. So maybe lots of it will cross over.
Then again, maybe not. So we can concentrate on the voltage drop at this point and see what's what.
To that end, did you verify that the Brown "I" wire from the starter relay is in good shape with no resistance and is getting added power during cranking to the ignition coil?
And how old is the starter? Maybe it's just starting to show it's age and pulling more amps than it should? We had one member here or somewhere that found their starter (I think it was a 460 engine?) was pulling 200 amps during start, rather than the expected 150 amps.
I personally felt that while it was more than desirable, that it was still well within normal parameters. But maybe to look into it anyway.
Maybe yours is pulling down too hard on the battery and weakening the spark.
Paul
Then again, maybe not. So we can concentrate on the voltage drop at this point and see what's what.
To that end, did you verify that the Brown "I" wire from the starter relay is in good shape with no resistance and is getting added power during cranking to the ignition coil?
And how old is the starter? Maybe it's just starting to show it's age and pulling more amps than it should? We had one member here or somewhere that found their starter (I think it was a 460 engine?) was pulling 200 amps during start, rather than the expected 150 amps.
I personally felt that while it was more than desirable, that it was still well within normal parameters. But maybe to look into it anyway.
Maybe yours is pulling down too hard on the battery and weakening the spark.
Paul
Lead Driver
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From: San Jose, CA
What you're seeing too though is the difference between a traditional '70's vintage Ford Bendix style starter vs the newer style with integrated (piggyback) solenoid. Called PMGR starters, for "permanent magnet, gear reduction" otherwise known as "mini starters" they pull less current during start, and therefor pull the battery down less.
Lots of us have converted to the newer style on various motors. I have not done it on my 400 yet but both of my 302's have been, and the 5.8/351 came with one.
Paul
Laughing Gas
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From: S.E. Louisiana;so far USA
If all the plugs are really soaked wet it will be difficult to get them to fire properly especially with a reduced spark energy. Perhaps it's getting too much fuel. Be sure the choke is not cutting off too much air.
Post Fiend
Joined: Apr 2002
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From: Waterloo, Iowa
The jerry rigged ignition that was presented to you is definitely some kind of clue, the spark at the plugs needs to be hot fat and blue-ish. A thin weak orange spark in the open air probably won't have enough juice to fire at all when plug is installed and under compression. I'd be inclined to fix that first before proceeding further, failing that even if the engine starts it probably won't run very well.
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The jerry rigged ignition that was presented to you is definitely some kind of clue, the spark at the plugs needs to be hot fat and blue-ish. A thin weak orange spark in the open air probably won't have enough juice to fire at all when plug is installed and under compression. I'd be inclined to fix that first before proceeding further, failing that even if the engine starts it probably won't run very well.
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Lead Driver
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From: San Jose, CA
The ground on the switch does not effect spark unless something else is way wrong too.
Your ignition switch does not use ground as a function for any of the major circuits, as it's just a simple switch that either opens (off) or closes (on) the contacts.
The only ground use is for the "prove out" or "proof out" (depending on where you first saw it written) that momentarily grounds one single circuit to test the dash warning lamp(s). This only happens during START anyway, so is non-essential for any other purpose.
Strange for the spark colors, but maybe it's just how it looks when going through the range of light. How wide is the gap your spark can jump? If you've got a tester than maybe you can tell how powerful it is. That's what they're for.
Try closing up the gap and see if the overall color changes.
Paul
Your ignition switch does not use ground as a function for any of the major circuits, as it's just a simple switch that either opens (off) or closes (on) the contacts.
The only ground use is for the "prove out" or "proof out" (depending on where you first saw it written) that momentarily grounds one single circuit to test the dash warning lamp(s). This only happens during START anyway, so is non-essential for any other purpose.
Strange for the spark colors, but maybe it's just how it looks when going through the range of light. How wide is the gap your spark can jump? If you've got a tester than maybe you can tell how powerful it is. That's what they're for.
Try closing up the gap and see if the overall color changes.
Paul
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That's a decent indicator that the meter is working as expected.
What you're seeing too though is the difference between a traditional '70's vintage Ford Bendix style starter vs the newer style with integrated (piggyback) solenoid. Called PMGR starters, for "permanent magnet, gear reduction" otherwise known as "mini starters" they pull less current during start, and therefor pull the battery down less.
Lots of us have converted to the newer style on various motors. I have not done it on my 400 yet but both of my 302's have been, and the 5.8/351 came with one.
Is the distributor new? Those ohm readings are for the distributor side of the harness, and measure the magnetic pickup coil (stator) inside the distributor. By the sound of it you were measuring the module itself. Not sure what the readings are supposed to be on that, but there are probably specs somewhere.
Paul
What you're seeing too though is the difference between a traditional '70's vintage Ford Bendix style starter vs the newer style with integrated (piggyback) solenoid. Called PMGR starters, for "permanent magnet, gear reduction" otherwise known as "mini starters" they pull less current during start, and therefor pull the battery down less.
Lots of us have converted to the newer style on various motors. I have not done it on my 400 yet but both of my 302's have been, and the 5.8/351 came with one.
Is the distributor new? Those ohm readings are for the distributor side of the harness, and measure the magnetic pickup coil (stator) inside the distributor. By the sound of it you were measuring the module itself. Not sure what the readings are supposed to be on that, but there are probably specs somewhere.
Paul
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Junior User
Joined: Aug 2019
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The ground on the switch does not effect spark unless something else is way wrong too.
Your ignition switch does not use ground as a function for any of the major circuits, as it's just a simple switch that either opens (off) or closes (on) the contacts.
The only ground use is for the "prove out" or "proof out" (depending on where you first saw it written) that momentarily grounds one single circuit to test the dash warning lamp(s). This only happens during START anyway, so is non-essential for any other purpose.
Strange for the spark colors, but maybe it's just how it looks when going through the range of light. How wide is the gap your spark can jump? If you've got a tester than maybe you can tell how powerful it is. That's what they're for.
Try closing up the gap and see if the overall color changes.
Paul
Your ignition switch does not use ground as a function for any of the major circuits, as it's just a simple switch that either opens (off) or closes (on) the contacts.
The only ground use is for the "prove out" or "proof out" (depending on where you first saw it written) that momentarily grounds one single circuit to test the dash warning lamp(s). This only happens during START anyway, so is non-essential for any other purpose.
Strange for the spark colors, but maybe it's just how it looks when going through the range of light. How wide is the gap your spark can jump? If you've got a tester than maybe you can tell how powerful it is. That's what they're for.
Try closing up the gap and see if the overall color changes.
Paul
I saw the blue spark and put them in my engine and it sounded a little better but it still didn't want to light off at all. Such a head scratcher
Post Fiend
Joined: Apr 2002
Posts: 19,311
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From: Waterloo, Iowa
As a really general observation in this situation you have a "pig in a poke" or whatever it's called right? It has never ran since you bought it because it was non-running and left in an advanced state of dumpster fire by the last guy who touched it.
You should back up, way way up, and start from the beginning. Check everything. As in Every Thing. Basics. Start with a compression test. Pull the valve covers and check that the valve timing or camshaft phasing is in the ballpark. Spark plug wires in the correct firing order? You'd be surprised how often this kind of stuff gets buggered up. Distributor & rotor stabbed in 180° out?
You should back up, way way up, and start from the beginning. Check everything. As in Every Thing. Basics. Start with a compression test. Pull the valve covers and check that the valve timing or camshaft phasing is in the ballpark. Spark plug wires in the correct firing order? You'd be surprised how often this kind of stuff gets buggered up. Distributor & rotor stabbed in 180° out?
FTE Legend
Joined: Nov 2015
Posts: 30,828
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From: Angier, NC
As a really general observation in this situation you have a "pig in a poke" or whatever it's called right? It has never ran since you bought it because it was non-running and left in an advanced state of dumpster fire by the last guy who touched it.
You should back up, way way up, and start from the beginning. Check everything. As in Every Thing. Basics. Start with a compression test. Pull the valve covers and check that the valve timing or camshaft phasing is in the ballpark. Spark plug wires in the correct firing order? You'd be surprised how often this kind of stuff gets buggered up. Distributor & rotor stabbed in 180° out?
You should back up, way way up, and start from the beginning. Check everything. As in Every Thing. Basics. Start with a compression test. Pull the valve covers and check that the valve timing or camshaft phasing is in the ballpark. Spark plug wires in the correct firing order? You'd be surprised how often this kind of stuff gets buggered up. Distributor & rotor stabbed in 180° out?
He is not getting any sign of it lighting off.
Dave ----
Lead Driver
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If it had fuel and spark and the distributor was anywhere , only half the plug wires hooked up and they were on the wrong plugs it's still going to do something.
.It doesn't take great spark to get an engine to try this is strange. what distributor is in it now you said you have several ?
I'm still thinking coil for lack of a better idea, is the coil in it now a resistor or non resistor type ?
.It doesn't take great spark to get an engine to try this is strange. what distributor is in it now you said you have several ?
I'm still thinking coil for lack of a better idea, is the coil in it now a resistor or non resistor type ?