Coil Sparks, but no spark at the plugs
#32
Thank you for the links; very informative. I have not done a compression test (although I have a record from the previous owner and it looks pretty consistent).
Keeping Occam's Razor theory in mind, I wonder if my new distributor cap could have a spot where spark is being lost or is it possible for the plastic bottom of the distributor to be a spot to lose spark intensity? Is ignition timing a possibility? I will double check that & compression test.
To clarify: when I said it would fire on ether, that was as long as it was being engaged with the starter.
Keeping Occam's Razor theory in mind, I wonder if my new distributor cap could have a spot where spark is being lost or is it possible for the plastic bottom of the distributor to be a spot to lose spark intensity? Is ignition timing a possibility? I will double check that & compression test.
To clarify: when I said it would fire on ether, that was as long as it was being engaged with the starter.
#33
Thank you for the links; very informative. I have not done a compression test (although I have a record from the previous owner and it looks pretty consistent).
Keeping Occam's Razor theory in mind, I wonder if my new distributor cap could have a spot where spark is being lost or is it possible for the plastic bottom of the distributor to be a spot to lose spark intensity? Is ignition timing a possibility? I will double check that & compression test.
To clarify: when I said it would fire on ether, that was as long as it was being engaged with the starter.
Keeping Occam's Razor theory in mind, I wonder if my new distributor cap could have a spot where spark is being lost or is it possible for the plastic bottom of the distributor to be a spot to lose spark intensity? Is ignition timing a possibility? I will double check that & compression test.
To clarify: when I said it would fire on ether, that was as long as it was being engaged with the starter.
#34
#35
Very good question, DS2 will jump a .045-050 gap ... but not a .070 gap.
It cant start on ether if there is not a spark jumping the gap on the plugs.
I would gap the plugs at .030, OK I do know that is a small gap , like what is used on a old point set up, but I am running out of ideas here.
If it make you feel better my airplane engine has the plugs gaped at .015-.019 .. and it wont start much past that gap.
All that is left is dwell issues which should be taken care of buy the DS2 IGN module.
In proper dwell causes a weak spark.
How to Make Sparks
Coil Dwell, I don't think its right causing weak spark. - evolutionm.net
Jim
It cant start on ether if there is not a spark jumping the gap on the plugs.
I would gap the plugs at .030, OK I do know that is a small gap , like what is used on a old point set up, but I am running out of ideas here.
If it make you feel better my airplane engine has the plugs gaped at .015-.019 .. and it wont start much past that gap.
All that is left is dwell issues which should be taken care of buy the DS2 IGN module.
In proper dwell causes a weak spark.
How to Make Sparks
Coil Dwell, I don't think its right causing weak spark. - evolutionm.net
Jim
#36
#37
If reluctant to spring for new, do you have the old pre-trouble parts? If already new, consider trying a different brand. I've had plenty of new parts bad from stock, so don't automatically rule out that possibility.
#38
Lots of back and forth in this thread, so forgive me if this has already been suggested, but have you tried a new distributor cap and rotor? If yes, have you tried new plug wires? Per the current symptoms, those things are pretty much your only possible culprits.
If reluctant to spring for new, do you have the old pre-trouble parts? If already new, consider trying a different brand. I've had plenty of new parts bad from stock, so don't automatically rule out that possibility.
If reluctant to spring for new, do you have the old pre-trouble parts? If already new, consider trying a different brand. I've had plenty of new parts bad from stock, so don't automatically rule out that possibility.
#40
As far as new parts bad from stock, I went through a lot of grief with a new cap and rotor many years ago on a different vehicle. After installing a whole boat load of new parts while tackling some major repairs, the engine ran much worse than before. I reached a lot of dead ends before realizing some of the new parts were probably bad.
Unfortunately, I went back to the same store without really thinking, and got MORE bad parts from the same defective batch. Talk about a headscratcher! I was tearing my hair out trying to figure it out, as everything still pointed to a bad cap or rotor. Out of desperation, I tried another bring from another store and then the engine once again purred like a kitten. This is why I recommend changing one part (or making one adjustment) at a time whenever possible, instead of a whole bunch of things at once.
Just something to consider. YMMV.
#41
Are the old parts pre- or post-trouble? The reason I ask is that you want to install a known good part (pre-trouble) if at all possible.
As far as new parts bad from stock, I went through a lot of grief with a new cap and rotor many years ago on a different vehicle. After installing a whole boat load of new parts while tackling some major repairs, the engine ran much worse than before. I reached a lot of dead ends before realizing some of the new parts were probably bad.
Unfortunately, I went back to the same store without really thinking, and got MORE bad parts from the same defective batch. Talk about a headscratcher! I was tearing my hair out trying to figure it out, as everything still pointed to a bad cap or rotor. Out of desperation, I tried another bring from another store and then the engine once again purred like a kitten. This is why I recommend changing one part (or making one adjustment) at a time whenever possible, instead of a whole bunch of things at once.
Just something to consider. YMMV.
As far as new parts bad from stock, I went through a lot of grief with a new cap and rotor many years ago on a different vehicle. After installing a whole boat load of new parts while tackling some major repairs, the engine ran much worse than before. I reached a lot of dead ends before realizing some of the new parts were probably bad.
Unfortunately, I went back to the same store without really thinking, and got MORE bad parts from the same defective batch. Talk about a headscratcher! I was tearing my hair out trying to figure it out, as everything still pointed to a bad cap or rotor. Out of desperation, I tried another bring from another store and then the engine once again purred like a kitten. This is why I recommend changing one part (or making one adjustment) at a time whenever possible, instead of a whole bunch of things at once.
Just something to consider. YMMV.
#42
#44
The next step will be to run 12 volts directly from the battery to BOTH the coil positive and the red wire on the DS2 IGN module.
This will eliminate all truck wiring. It will / should start with your remote starter.
Full voltage at the coil will help deliver a hotter spark. Check this at the coil wire, spark tester to ground.
Jim
This will eliminate all truck wiring. It will / should start with your remote starter.
Full voltage at the coil will help deliver a hotter spark. Check this at the coil wire, spark tester to ground.
Jim
I will get some gas for the other tank in a day or two when we go to town.
#45