318 Won't Start? And I tested as much as I could I think?

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VolksDuster

Back Yard Guy
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Sep 22, 2013
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First I would like to say sorry for being away for so long and not being more in tune.
Second to say sorry for talking about the common issue that has posts everywhere, but I couldn't find anything that directly laid out the issues together.
And Now.....
About a year ago I stopped driving the car due to non car related stuff. I had been starting up every month to get it hot and fully lubed. Toward the winter this sort of stopped and then 4 months later I tried to take to a car club and it ran like crap. As if it was misfiring combined with down cylinders, really rough. And now a month after that I have gotten no farther, just more confused.
So I tried starting it again and the same thing had occurred (sounds like misfiring combined with down cylinders, really rough). First thought was the octane had gotten low in the gas, so I added some to no avail. The next few times of trying to start it were over a few days and it seem to worsen until finally it wouldn't fire up not even for a second or two.
From there I went back to basics, gas, air and fire... the carb is shooting clean streams out of the top so that should have been at least enough to fire for a second or two. Also tried starting fluid with no success.
So with a wide open throttle and a bit of fuel from the carb if should fire with spark?
I couldn't get it to go so I checked the coil directly with a plug grounded to the manifold, and there is a good spark. Then moved on to the plugs on the cylinders and they have spark, checked the same way. After that I moved on to see if the timing was just way out on the distributer, cylinder 1 plug wire was lining up with the rotor strait forward on the block at TDC. Then I tried rotating the distributer in both directions to try and locate a spark with no luck. So then I thought maybe It's out 180 degrees, tried swapping it around with no luck. After that, just for curiosity I checked compression and got approximately 125 psi all around. Then moved on to the 4 post ballast resistor and had 4.70 resistance with the car in the on positon not running across the top auxiliary posts and then had the 4.70 on the lower main posts when cranking it over. I tried an extra old ICM but there was no difference, Is it possible for the voltage regulator on the firewall can cause this?
I've replace the resistor just in case along with rotor, cap, wires, and plugs. Also the distributer and carburetor were replaced about 2 years ago.
Mostly..... I'm now lost and I'm not sure where to go from here? Any suggestions or thoughts would be great.

Thanks
 
Replace the plugs?
They could be fouled from bad gas. Drain fuel, add fresh and
A good splash of sea foam to stabilize it. I would suggest pulling carb and going through it,bowl is likely polluted with green slime from bad gas.
 
1...You can set the timing with a light "on the starter" If you have a light I highly suggest this because it should produce a nice "even rhythum" of spark, and might show up a problem, like a flakey pickup/ reluctor

2...If you don't have a light STATIC time it. I assume you have Mopar breakerless?

You MUST determine if the no1 is "ready to fire" (compression stroke) or not

There is only two ways to do this.....

A.....If either valve cover is off for any reason, rotate the engine so the timing marks are on TDC then look at no 1 or no6 valves. They will either be "both closed" or "both a little open." If there is any question, rotate the engine back and forth (wrench) and if both valves immediately move, THEY ARE OPEN (split overlap)

Whichever set of valves is closed THAT cylinder is ready to fire

B......The other method is remove no1 plug, stick your finger in, and bump the engine til you feel compression. Stop, look for the marks "coming up" and wrench the engine so the marks ARE NOT on TDC, but rather "where you want timing" AKA 10--15 BTC depending, stock engine, or hot cam

NOW THE ENGINE IS ready to be timed

Set the dist in so the rotor is pointing to the no1 tower, or wherever the rotor points, put no1 wire IN that tower. Now rotate the dist. body CW (retard) and slowly bring back until the reluctor is centered in the pickkup coil core

Alternatively, you can turn on the key and "wiggle" the dist. back and forth across the pickup and "feel" for the spark with a tester

AT THIS POINT the timing should be close enough to RUN

Forget fuel. Assume it's stale. Use FRESH gas. Make sure the plugs are new or DRY Throw a little gas down it it should FIRE. About a tablespoon

=================================

SPARK TESTING. I always test right at the coil tower with a SOLID wire and something like a test gap. The system should produce an nice hot spark at least 3/8" and more typical, 1/2" long, hot and blue

==================================

WHEN CRANKING............If you crank using a jumper at the starter relay, you get a WEAKER spark than when using the key, because the coil is going through the ballast resistor. the bypass circuit in the ignition switch is NOT ACTIVE under these conditons

So if you are careful, you can jumper 12V direct to the coil, but do NOT leave that connected very long, only while trying to start

Inspect the reluctor/ pickup for rust, debri, strike damage. Check the dist shaft for play (bushings) and wobble. Check the cap and rotor, the cap for dirt, moisture, wear, material migration from the contacts, it should be CLEAN. Check the rotor for spark "punch through" to the shaft. THIS HAPPENS, but not very often
 
you didn't mention year, make, model, nor electronic or points. when you said you had spark at coil, but not at plugs, I would have guessed bad/mismatched rotor/cap, or possibly bent/broken center contact at rotor or cap, but you said you've replaced them since, so I'm fresh out of ideas.
 
My guess is;No oil on the cylinder walls.
Put a couple of shots of oil in each hole, let it sit for a few minutes, roll the engine over a bit and give her another couple of squirts. Then let it sit for 30 minutes or more. Crank it over to blow out the excess, yeah the oil will come flying outta there and make a huge mess, so figure out a way to minimize the clean up.
Clean the plugs and reinstall them. Set the choke, give her quarter throttle, and with a fully charged battery, twist the key. When she fires up, hold her at about 1500/1800 for about 30 seconds, then let her return to idle. Now jump out and open the choke blade fully, and stick something in there to keep it open until the engine is warmed up.

Then figure out what's wrong with the choke. Yeah, I'm guessing.
 
My guess is;No oil on the cylinder walls.

OP said:

"After that, just for curiosity I checked compression and got approximately 125 psi all around."

so I took it he meant "he checked that lately"

But that is sure something to keep in mind
 
Had the same thing happened to two different vehicles. And in the end it wound up being watered down gas.

One of the vehicles, I had just filled it up, drove it home and it wouldn't run after that, tried everything. Had it hauled into a shop and they found 11 gallons of water in the tank.
 
Had the same thing happened to two different vehicles. And in the end it wound up being watered down gas.

One of the vehicles, I had just filled it up, drove it home and it wouldn't run after that, tried everything. Had it hauled into a shop and they found 11 gallons of water in the tank.

yup...I've bought several tanks of crap gas from the same place. It's on my way wherever I go so I told the manager what has happening and he tells me he sells the finest, cleanest fuel in central Washington.

I have to fill up in a few days. We'll see what happens. I promised him if my truck ran like crap again I was going to make him drive it and then dump his **** fuel and put some good fuel in it and see the change. That joker owes me several tanks of gas.
 
I couldn't get it to go so I checked the coil directly with a plug grounded to the manifold, and there is a good spark. Then moved on to the plugs on the cylinders and they have spark, checked the same way.
OP, your test of spark is no good. A spark jumping a spark plug gap in open air is meaningless; it takes only a few thousand volts to jump that small gap in open air but will take 20,000 volts to jump the same gap in a compressed fuel-air mix. You have to test spark in open air across a gap that is 1/4" to 3/8" wide; if it jumps that, then it will jump the small spark gap in a compressed fuel-air mixture.

So rerun your spark test with a spark plug wire set in such a way so as to form a 1/4" gap from tip to metal and retry. Do as you did before: start with the spark wire from the coil's spark tower, then move on to one individual spark plug's wire.

BTW, your resistor checks don't make total sense. Pull the connections off and measure resistance on the 2 halves; one half should be around 5 ohms and the other < 1 ohm. Then check voltage to coil + when cranking; it should be 10-11 volts. That will check to see if your coil bypass for startup is working. If it is not, then the voltage will be lower, in the 6-9 volt range. The voltage may pulsate at this test point.

BTW, the one part in the system you did not replace is the condensor... that can cause bad spark when it goes bad.

If the spark is good across a wide test gap in air, then put about 1/2 tsp of new gas down the carb throat, and with the throttle held slightly open not wide open), it should fire for a second to so. That will test the fuel condition.

And a fresh set of plugs is a good suggestion. Gas-fouled will take more to fire off.
 
Old gas in some situations will not burn when engine is cold. But it will run in a warm engine. My old truck had stale fuel, wouldnt fire.
Primed it a few times with fresh, moved where i could work on it and got that fuel out.
 
CHANGE THE PLUGS!
If there was no joy even with starting fluid, it's most likely spark related.
There was no reason to rotate the distributor 180* if everything was good before you stopped driving it.
IIRC, at TDC, the rotor should point to the forward-most intake bolt on the driver side of the engine but it's been a long time since I had to do that.
 
Replace the plugs?
They could be fouled from bad gas. Drain fuel, add fresh and
A good splash of sea foam to stabilize it. I would suggest pulling carb and going through it, bowl is likely polluted with green slime from bad gas.
I replace the plugs, wires, cap, and rotor on Saturday and on Sunday replaced the ballast and still no change. As for fuel, I've left gas sit a lot longer than that in small engines and had no issue. But there was a quarter of a tank and I added a whole bottle of octane booster thinking that would be enough. Same for the carb, it's only a year old and if it was clogged I should be able to at least fire for a moment on starting fluid but it's not firing up.
 
Ditch that electronic distributor and test with a good old kettering points type. About as failsafe as you can get. Ive ran varnished crap gas in my 7:1 lawnmower: it runs, just smells funny.
 
1...You can set the timing with a light "on the starter" If you have a light I highly suggest this because it should produce a nice "even rhythum" of spark, and might show up a problem, like a flakey pickup/ reluctor

2...If you don't have a light STATIC time it. I assume you have Mopar breakerless?

You MUST determine if the no1 is "ready to fire" (compression stroke) or not

There is only two ways to do this.....

A.....If either valve cover is off for any reason, rotate the engine so the timing marks are on TDC then look at no 1 or no6 valves. They will either be "both closed" or "both a little open." If there is any question, rotate the engine back and forth (wrench) and if both valves immediately move, THEY ARE OPEN (split overlap)

Whichever set of valves is closed THAT cylinder is ready to fire

B......The other method is remove no1 plug, stick your finger in, and bump the engine til you feel compression. Stop, look for the marks "coming up" and wrench the engine so the marks ARE NOT on TDC, but rather "where you want timing" AKA 10--15 BTC depending, stock engine, or hot cam

NOW THE ENGINE IS ready to be timed

Set the dist in so the rotor is pointing to the no1 tower, or wherever the rotor points, put no1 wire IN that tower. Now rotate the dist. body CW (retard) and slowly bring back until the reluctor is centered in the pickkup coil core

Alternatively, you can turn on the key and "wiggle" the dist. back and forth across the pickup and "feel" for the spark with a tester

AT THIS POINT the timing should be close enough to RUN

Forget fuel. Assume it's stale. Use FRESH gas. Make sure the plugs are new or DRY Throw a little gas down it it should FIRE. About a tablespoon

=================================

SPARK TESTING. I always test right at the coil tower with a SOLID wire and something like a test gap. The system should produce an nice hot spark at least 3/8" and more typical, 1/2" long, hot and blue

==================================

WHEN CRANKING............If you crank using a jumper at the starter relay, you get a WEAKER spark than when using the key, because the coil is going through the ballast resistor. the bypass circuit in the ignition switch is NOT ACTIVE under these conditons

So if you are careful, you can jumper 12V direct to the coil, but do NOT leave that connected very long, only while trying to start

Inspect the reluctor/ pickup for rust, debri, strike damage. Check the dist shaft for play (bushings) and wobble. Check the cap and rotor, the cap for dirt, moisture, wear, material migration from the contacts, it should be CLEAN. Check the rotor for spark "punch through" to the shaft. THIS HAPPENS, but not very often

I had used a compressing tester as well the finger method and they matched so I don't think it's out 180 and made sure the rotor was pointing forward with compression in no1 cylinder. As for the cap and wires, with the rotor pointing forward I rotated the distributer back and forth to find the middle which lined up a post almost perfectly right on.

And I even tried starting fluid at the end of each attempt of the peddle with no success.
I will try draining the gas in the next day or two to be sure there is new fuel, but there was only a quarter of a tank and I added a bottle of octane to help?

When you say "Now rotate the dist. body CW (retard) and slowly bring back until the reluctor is centered in the pickkup coil core" Do you mean center a cog on the wheel with the magnet?

I don't have a spark plug tester but I did take another plug wire with a plug and went directly off the coil to ground and had spark.
As for cranking I only try starting with the key.
I'll double check the reluctor and the rest of the distributer to be sure tonight, but the distributer is only about a year old anyway.

frig this is frustrating
 
you didn't mention year, make, model, nor electronic or points. when you said you had spark at coil, but not at plugs, I would have guessed bad/mismatched rotor/cap, or possibly bent/broken center contact at rotor or cap, but you said you've replaced them since, so I'm fresh out of ideas.

Sorry I thought I mentioned this is a 73' Plymouth Duster Automatic with a 318 and uses a magnetic pickup and an Ignition Control Module on the fender with the 4 post ballast.
I thought I has said hot quite as much spark at the plug but the spark is reaching there.
 
OP, your test of spark is no good. A spark jumping a spark plug gap in open air is meaningless; it takes only a few thousand volts to jump that small gap in open air but will take 20,000 volts to jump the same gap in a compressed fuel-air mix. You have to test spark in open air across a gap that is 1/4" to 3/8" wide; if it jumps that, then it will jump the small spark gap in a compressed fuel-air mixture.

So rerun your spark test with a spark plug wire set in such a way so as to form a 1/4" gap from tip to metal and retry. Do as you did before: start with the spark wire from the coil's spark tower, then move on to one individual spark plug's wire.

BTW, your resistor checks don't make total sense. Pull the connections off and measure resistance on the 2 halves; one half should be around 5 ohms and the other < 1 ohm. Then check voltage to coil + when cranking; it should be 10-11 volts. That will check to see if your coil bypass for startup is working. If it is not, then the voltage will be lower, in the 6-9 volt range. The voltage may pulsate at this test point.

BTW, the one part in the system you did not replace is the condensor... that can cause bad spark when it goes bad.

If the spark is good across a wide test gap in air, then put about 1/2 tsp of new gas down the carb throat, and with the throttle held slightly open not wide open), it should fire for a second to so. That will test the fuel condition.

And a fresh set of plugs is a good suggestion. Gas-fouled will take more to fire off.

All new Saturday from plugs to the rotor with a ballast on Sunday.
That is good to know information about the gap testing. I didn't know that there was that much of a pressure issue. I will retest the coil and plugs tonight. But they are all new with no change in lack of starting.

As for the ballast, I tried to go by the book which I understood it stated that both upper and lower pair should both read around 4.75 ohms with the key in the on position.
However, I only got a reading on the top pair (4.75 ohms) under this condition and had full resistance (no change on the meter) on the bottom pair unless cranking over when I got the same reading as the top.
As for when the resister was unhooked there was no resistance on the top or bottom pair using the new ballast, was well as the one taken off.
I assume even with bad gas it should at lest fire for a second on starting fluid if spark is good.

Since you suggest
"Pull the connections off and measure resistance on the 2 halves; one half should be around 5 ohms and the other < 1 ohm. Then check voltage to coil + when cranking; it should be 10-11 volts. That will check to see if your coil bypass for startup is working. If it is not, then the voltage will be lower, in the 6-9 volt range. The voltage may pulsate at this test point.
BTW, the one part in the system you did not replace is the condensor... that can cause bad spark when it goes bad."
I will retest everything and I'm not sure about the condenser? I wasn't aware of any? where is it located? and how can I test it?
 
I don't have a spark plug tester but I did take another plug wire with a plug and went directly off the coil to ground and had spark.
I hope you don't mind my saying this again, but testing the spark across the gap of a spark plug in open air is a meaningless test. A very weak spark can jump that small gap in open air but will NEVER jump the same spark plug gap in a compressed fuel-air mixture in the combustion chamber. Since you never got fire even with starting fluid, it points to the ignition. But you have to stop testing your spark wrong ; it's just misleading you into thinking that it is a good spark if you test with a plug in open air.

I don't see you mentioning a new coil in this, or a new condensor. Either can cause weak/no spark.
 
I hope you don't mind my saying this again, but testing the spark across the gap of a spark plug in open air is a meaningless test. A very weak spark can jump that small gap in open air but will NEVER jump the same spark plug gap in a compressed fuel-air mixture in the combustion chamber. Since you never got fire even with starting fluid, it points to the ignition. But you have to stop testing your spark wrong ; it's just misleading you into thinking that it is a good spark if you test with a plug in open air.

I don't see you mentioning a new coil in this, or a new condensor. Either can cause weak/no spark.


He doesn't have a condenser.
 
I hope you don't mind my saying this again, but testing the spark across the gap of a spark plug in open air is a meaningless test. A very weak spark can jump that small gap in open air but will NEVER jump the same spark plug gap in a compressed fuel-air mixture in the combustion chamber. Since you never got fire even with starting fluid, it points to the ignition. But you have to stop testing your spark wrong ; it's just misleading you into thinking that it is a good spark if you test with a plug in open air.

I don't see you mentioning a new coil in this, or a new condensor. Either can cause weak/no spark.

Sorry, I thought I mentioned the coil in the opening of the thread, there is also a new coil on top of the wires, plugs, cap, rotor, and ballast. And I just got back from the car and testing more spark...
I found a spark tester to use and set the gap to 3/8'' and connected to #1 and good ground just to check before back tracking and the was a long good spark going right to the cylinder.
As for the condenser, I only know of the Control Unit, Ballast, Voltage regulator,
 
1...You can set the timing with a light "on the starter" If you have a light I highly suggest this because it should produce a nice "even rhythum" of spark, and might show up a problem, like a flakey pickup/ reluctor

2...If you don't have a light STATIC time it. I assume you have Mopar breakerless?

You MUST determine if the no1 is "ready to fire" (compression stroke) or not

There is only two ways to do this.....

A.....If either valve cover is off for any reason, rotate the engine so the timing marks are on TDC then look at no 1 or no6 valves. They will either be "both closed" or "both a little open." If there is any question, rotate the engine back and forth (wrench) and if both valves immediately move, THEY ARE OPEN (split overlap)

Whichever set of valves is closed THAT cylinder is ready to fire

B......The other method is remove no1 plug, stick your finger in, and bump the engine til you feel compression. Stop, look for the marks "coming up" and wrench the engine so the marks ARE NOT on TDC, but rather "where you want timing" AKA 10--15 BTC depending, stock engine, or hot cam

NOW THE ENGINE IS ready to be timed

Set the dist in so the rotor is pointing to the no1 tower, or wherever the rotor points, put no1 wire IN that tower. Now rotate the dist. body CW (retard) and slowly bring back until the reluctor is centered in the pickkup coil core

Alternatively, you can turn on the key and "wiggle" the dist. back and forth across the pickup and "feel" for the spark with a tester

AT THIS POINT the timing should be close enough to RUN

Forget fuel. Assume it's stale. Use FRESH gas. Make sure the plugs are new or DRY Throw a little gas down it it should FIRE. About a tablespoon

=================================

SPARK TESTING. I always test right at the coil tower with a SOLID wire and something like a test gap. The system should produce an nice hot spark at least 3/8" and more typical, 1/2" long, hot and blue

==================================

WHEN CRANKING............If you crank using a jumper at the starter relay, you get a WEAKER spark than when using the key, because the coil is going through the ballast resistor. the bypass circuit in the ignition switch is NOT ACTIVE under these conditons

So if you are careful, you can jumper 12V direct to the coil, but do NOT leave that connected very long, only while trying to start

Inspect the reluctor/ pickup for rust, debri, strike damage. Check the dist shaft for play (bushings) and wobble. Check the cap and rotor, the cap for dirt, moisture, wear, material migration from the contacts, it should be CLEAN. Check the rotor for spark "punch through" to the shaft. THIS HAPPENS, but not very often

Just another question about the distributor. When dropping in the distributer with the rotor pointing forward which seems slightly toward the no1 cylinder should the distributer be turned all the way retarded then forward to the first post that lines up? Or should I find the mid point between full advance and full retard, then use the closest tower from there?
 
Distributor all the way back to hit the firewall, then pulled forward to align first vane, all with timing index marks at about 10 to 15* advance indicated, and with #1piston at near TDC on the compression stroke.
Wire cap accordingly
 
OP, your test of spark is no good. A spark jumping a spark plug gap in open air is meaningless; it takes only a few thousand volts to jump that small gap in open air but will take 20,000 volts to jump the same gap in a compressed fuel-air mix. You have to test spark in open air across a gap that is 1/4" to 3/8" wide; if it jumps that, then it will jump the small spark gap in a compressed fuel-air mixture.

So rerun your spark test with a spark plug wire set in such a way so as to form a 1/4" gap from tip to metal and retry. Do as you did before: start with the spark wire from the coil's spark tower, then move on to one individual spark plug's wire.

BTW, your resistor checks don't make total sense. Pull the connections off and measure resistance on the 2 halves; one half should be around 5 ohms and the other < 1 ohm. Then check voltage to coil + when cranking; it should be 10-11 volts. That will check to see if your coil bypass for startup is working. If it is not, then the voltage will be lower, in the 6-9 volt range. The voltage may pulsate at this test point.

BTW, the one part in the system you did not replace is the condensor... that can cause bad spark when it goes bad.

If the spark is good across a wide test gap in air, then put about 1/2 tsp of new gas down the carb throat, and with the throttle held slightly open not wide open), it should fire for a second to so. That will test the fuel condition.

And a fresh set of plugs is a good suggestion. Gas-fouled will take more to fire off.


Also the resistor test was an error on my part. They are good, 5.2 on the top and 2.0 on the bottom when disconnected. I accidentally had it on 20k testing, duh... I need to keep tools a little clean so I can see the white letters better.
 
Distributor all the way back to hit the firewall, then pulled forward to align first vane, all with timing index marks at about 10 to 15* advance indicated, and with #1piston at near TDC on the compression stroke.
Wire cap accordingly
Thank you, I will reset that tomorrow any try it again. I'm centered in the distributer rotation currently which did give me a bit of a single fire and backfire with it.
 
If you have spark, fiddling with the resistor test is not necessary. they might quit completely or become intermittent. Since you seem to have good spark ( and steady?) that part seems OK
 
You might tuck this into the back of your brain "for later" when things settle down. I, like many others converted my ignition to an HEI module. But I ALSO built an HEI -in-a-box with a coil for an "emergency" ignition, and it has become VERY handy AKA firing up/ testing used engines!!!

4pin-jpg.jpg


hwlcfa-jpg.jpg


34nf6l0-jpg.jpg


Putting it to practical use: Firing up a used EFI magnum on a carb and this ignition box:

If you read this thread I have some pointers on setting timing

LMFAO Anybody figure out what this is?

img_1036-jpg.jpg
 
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