Help needed with drivability issue

[mr. fix it]

I'm Stumped...

ok so I've been trying to wrestle this beast for the past month now.
Changed ignition wiring, (with a used set because the Poly 318's seem to have an elusive wire length that no parts supplier has a clue on what to order for my engine)

Changed the coil and this engine will not settle down.
I have rebuilt the carb and screwed with that float settings, and accelerator pump adjustment.
Compression check show 170psi across the board.
So it leaves me to think that there is an issue with the electronic ignition part of the engine.

The fuel side of things has seen a new fuel filter along with the build.

I swapped out the fuel pump because from time to time the fuel filter is pretty much empty.
Toady it was again with a full tank of new gas.

So I swapped it out with a used fuel pump but this was worse as it now stall out at highway speeds.

Crazy thing is that it runs fine sometimes then not.
Yesterday started off with it not wanting to run at all then after fiddling with the spark plug wiring it ran pretty good all day.
Today it was back to the same "I'm not going to run right" scenario.

It does have the Chrysler electronic ignition from a 70's Mopar. Not sure what it is from...

So do I continue to simply replace all parts that are ignition and fuel related with the hope that I find this demon that is causing me grief?


Any suggestions here???

 

[Big_John]

Check the fuel pump first. Disconnect the line and let it squirt into a coffee can. It should be a decent volume of gas as you turn the engine over.

My next thought is the ECU. I have heard of intermittent issues like this tracing back to the ECU. You should have a spare to carry anyway even if it isn't the cause.

 

[mr. fix it]

I am ordering another new FP and will check to see if I have a spare ECU.. Thx.

the current one has about 2000 miles usage and the old one who know but it was worse than the new one for sure.

Both bench tested out pretty good I thought

 

[67Monaco]

Check for loose/bad ground somewhere in the ignition circuit. I've seen all sorts of weird intermittent problems due to funky grounds. add a ground from ECU to battery just to eliminate any potential there.

 

[mr. fix it]

I was thinking of adding one from the distributor to the ground strap as well, Thx.

 

[BJS racing]

I just had the same issue on a 64 chevy of a neighbors that was almost the exact same issue you are describing. His problem was the fuel pump and more importantly the ground for the fuel pump. Checked to see how much fuel was coming out of the pump and damn near nothing. He has dropped over $1000 on chasing this problem with a shop and we had it fixed and running in less than an hour and for about $100. To say he was pretty pissed is putting it pretty lightly.

 

[mr. fix it]

I just had the same issue on a 64 chevy of a neighbors that was almost the exact same issue you are describing. His problem was the fuel pump and more importantly the ground for the fuel pump. Checked to see how much fuel was coming out of the pump and damn near nothing. He has dropped over $1000 on chasing this problem with a shop and we had it fixed and running in less than an hour and for about $100. To say he was pretty pissed is putting it pretty lightly.

I am ordering another FP as well to make sure this is not the issue. thx

 

[67Monaco]

I just had the same issue on a 64 chevy of a neighbors that was almost the exact same issue you are describing. His problem was the fuel pump and more importantly the ground for the fuel pump. Checked to see how much fuel was coming out of the pump and damn near nothing. He has dropped over $1000 on chasing this problem with a shop and we had it fixed and running in less than an hour and for about $100. To say he was pretty pissed is putting it pretty lightly.

When I put my Carter in two weeks ago I ran the ground all the way back to the battery. Being around aftermarket electric pumps during my late teens and twenties we realized bad ground kills electric pumps quicker than anything else.

 

[Big_John]

I am ordering another FP as well to make sure this is not the issue. thx

Even with the new pump, you really need to check the volume. It could be a number of things, like a bad pickup, a plugged or porous gas line or even something wrong with the eccentric that drives the pump (doubtful, but possible). Since you said it was worse with the used pump, it makes me suspicious of something in the fuel system.

 

[mr. fix it]

Agreed on the fuel suggestions
I have new lines front to back
Tank was clean but I have checked since it is now on a full tank

Filter replaced I tried an old pump yesterday and condition got worse
Picking up a new pump today thanks to my wife doing that for me

 

[BJS racing]

I just use something like the Mr. Gasket pulse pump from the local parts store and they work find unless you are doing a stout motor set up.

https://www.summitracing.com/parts/...D79LD9pZl9MAvY4pL-8yeWbEwMfgVIeXH-xoCFoLw_wcB

 

[stubs300]

I'm Stumped...

ok so I've been trying to wrestle this beast for the past month now.
Changed ignition wiring, (with a used set because the Poly 318's seem to have an elusive wire length that no parts supplier has a clue on what to order for my engine)

Compression check show 170psi across the board.
So it leaves me to think that there is an issue with the electronic ignition part of the engine.


It does have the Chrysler electronic ignition from a 70's Mopar. Not sure what it is from...

So do I continue to simply replace all parts that are ignition and fuel related with the hope that I find this demon that is causing me grief?
Any suggestions here???

Given what you say here, you leave a lot left unknown. What are we working on, year, make model, etc.? What did you do to make this run worse? What haven't you done?
With that being said< I think you have ignition problems. Are you running the newer Voltage Reg. that's required when you convert to Elec. Ignig.? I'd venture to say a big NO!
Read, heed, and read again and fix what's F'ed up, esp. what's said in the middle of the page. Good Luck
charging system overview

 

[mr. fix it]

Hi Stubs
Well here is what I have.
It's a poly 318 the has a 318 Stock 70's electronic distributor with an external 4 pin ECU orange flavour conversion
Stock 2 pole ballast resistor along with it. Stock 12 volt coil(B/N this past week)
I have an electronic volt regulator as well with a 50 amp alternator.
New dist cap, rotor, spark plugs

Changed out wires after finding one burnt and another metal end fallen off when I removed the set
Rebuilt the carburetor after having to grind to a sudden stop about 2 months ago.
then the stalling started.
I new BN gas lines from gas tank to front all new rubber hoses and clamps.
Cleaned gas tank
B/N sending unit.
Though it was coincidence that the car started stalling pulling around corners and accelerating.
Got worse seemed fine while idling.
built carb and it was somewhat better but got worse again after a day.

ran like crap first thing Sunday morning, stopped fiddled with SP wires nad elctronic ignition connections and it got much better.
Drove fairly well for the day to Simcoe and back.
Monday morning back to the old tricks of running like a bag of dirt.

Tries the fiddle with wiring again but no good results.
checked fuel filter and it was full but then it ran to half full and stayed there.Changed outhe pump wit ha used one and it was worse than the new one.
At first it was good but then it drained dry.

Have in hand a B/N ECU and Fuel pump to install tonight if i get the time.

I'm taking a step back and starting the diagnostic over again to make sure i am not missing a step.
How's that for details?

 

[70bigblockdodge]

Is the pick up/sending unit in tank new , I had a pin hole in mine that made car very temperamental plus ground on ECU made it shut off after 4500.

 

[mr. fix it]

interesting... I didn't get to the electrical other than replacing the ballast resistor. Found 3 hair line cracks in the porclian

I tried to replace the fuel pump tonight but the supplier gave my wife the wrong one...
I installed the original BN one and rechecked float settings which seemed to make things worse for me.

Now i see that the engine is flooding UGHHH!!! and the fuel filter is being sucked dry or draining back when the engine is turned off...
There should be a check valve in the FP to prevent that from happening.
or,
Also could be some **** in the tank clogging the pick up tube filter so I will drain the gas enough to see if there is any crap in the tank.
if there is enough suction it may be causing the fuel to be drawn back down the line as soon as the engine is turned off?

 

[cantflip]

Stock 2 pole ballast resistor along with it. Stock 12 volt coil(B/N this past week)

I have seen your work here and read the advice you give others... you're missing the symptom information we might use for a logical diagnostic. I know you're better, you just need a moment I think.

Problems during:

High load conditions - secondary ignition issues...

Higher engine speeds/loads- could be fuel starvation.

Low engine speeds idle could be rich or lean (vacuum leaks?)- spark plugs would tell... black or white porcelain. Black exhaust smoke for rich...

Random seeming symptoms are often primary ignition issues... loose power or ground wires... sloppy distributor or lose of signal from the pick up...

If the carb was flooding I would expect it to smoke, stink and clear up with higher rpm's... the only way the carb could suck fuel would be if you ran a vacuum line to the bowl vent. Drainback would only be an issue for long crank starting.

You may have the right answer, I just couldn't pick it up from the few symptoms I see in the thread. I did highlight the coil... ballast resistors would be used to reduce voltage to a 6 volt coil. 12 volt coils need the full 12 to deliver adequate spark...

I hope this didn't come off too gruff, I have read through this about 4 different times now trying to find a way to help... without the symptoms spelled out in detail, it's all just guesses and "what worked for me" stuff.

 

[mr. fix it]

I understand CantFlip.

I don't get easily offended especially when I am asking for help.
Beggers have to be careful not to bite off the hand that is feeding them.

I do appreciate the replies here & realize that others look to me for assistance and this one has me chasing my tail as you can see.
Once this is fixed we can all sit back and have a virtual beer together and I'll give full credit to the members that suggested what it might be.

I thought I was taking a good approach to this issue but seem to have lost some direction on this.
I suspect that there are 2 issues going on here at once which is having a domino effect on diagnosing this problem correctly

I'll give it my best shot to clarify what is going on.
This all seemed to start off simply enough with a stalling issue from idling stop approximately 2 months ago now.
Coincidentally I had made a bit of a panic stop after someone stopped short in front of me the same evening.
Engine would run fine otherwise if I nursed it off idle then after it hit the secondary circuits the car ran fine.

Suspecting I had stirred up some sediment in the carb bowl and possibly ripped Accelerator pump or now had some sediment in the circuits, I ordered a rebuild kit for the carb.

Rebuilt the carb and rechecked settings
Replaced filter filter suspecting some type of blockage. not totally blocked but a bit hard to blow through
I have checked for vacuum leaks. none found.
I by-passed all vacuum related accessories during the leak check.
Checked fuel pump pressure = +6 psi. this pump is now 2 years old.
New fuel filter was full at all times until I ran low of gas one evening.
After a refill filter was filled again
Did not suspect any further fuel delivery issues at this point
Still had off idle stalling
Made recommended FSM adjustments with no better results

I turned to look at the electrical at this point

I checked and adjusted timing
It had moved on me twice and when it was not running right seemed to jump around a lot this would be typical of the #1 SP wire not firing correctly which was one of the bad wires
Checked timing chain and gears - 3 degrees play detected (not enough to place this at fault)
Discovered a burnt ignition wire along with a burnt dist cap pole #1 cylinder
Replaced the dist cap, wire and discovered another ignition wire with a loose end - still trying to find a source that will get me the right wires for a poly.
Replaced Rotor & coil as a PM. - parts are cheap enough so why not?
Replaced spark plugs as well. 2 were not firing - equated to the ones that had the bad wires
Checked distributor itself.
Mechanical weights are free
Vacuum advance is good and holds vacuum

I have not done any electronic diag's on the guts itself though

I have not yet checked grounding issues since I am not convinced this is the problem.
BUT I will do that though tonight as suggested here.

Anyone who has suggested I check is right that I should do this regardless of the time that has elapsed since I had everything apart.
It may turn out to be a loose screw. in the engine or my head ") LOL!

When I tore the front clip off a few years back now I cleaned all ground contact points.
Replaced all electrical related wiring for the engine during the rebuild
Not to say that I do not have the ground issue still

Finally, an interesting clue to all of this is that on Sunday when we went to the Simcoe car show the car wanted to stall every time I touched the gas.

I drove it about 10 miles doing this and was about to turn around for home.
I popped the hood and fiddled with the ignition wiring, wriggled the wiring to the ECU and distributor.
Got back in and it ran much better the remaining 40+ miles there and back.
In fact it pulled away from a stop really well no stumble detected at all.
The next morning the issue was back but not nearly like it was on the Sunday.
Checked fuel filter and it was nearly empty so I refocused on the fuel delivery
( I had filled up along the way home)

For now I have to deal with the flooding fuel issue I caused for myself then look at the electrical portion again.

I'm confident it will be fixed and it will probably something silly like the extra keys on the ashtray were shorting out the cigarette light when I turned the corner

Keep the suggestions coming. I hope this helps everyone understand what is going on here.

 

[cantflip]

I understand CantFlip.

I don't get easily offended especially when I am asking for help.
Beggers have to be careful not to bite off the hand that is feeding them.

I do appreciate the replies here & realize that others look to me for assistance and this one has me chasing my tail as you can see.
Once this is fixed we can all sit back and have a virtual beer together and I'll give full credit to the members that suggested what it might be.

I thought I was taking a good approach to this issue but seem to have lost some direction on this.
I suspect that there are 2 issues going on here at once which is having a domino effect on diagnosing this problem correctly

I'll give it my best shot to clarify what is going on.
This all seemed to start off simply enough with a stalling issue from idling stop approximately 2 months ago now.
Coincidentally I had made a bit of a panic stop after someone stopped short in front of me the same evening.
Engine would run fine otherwise if I nursed it off idle then after it hit the secondary circuits the car ran fine.

Suspecting I had stirred up some sediment in the carb bowl and possibly ripped Accelerator pump or now had some sediment in the circuits, I ordered a rebuild kit for the carb.

Rebuilt the carb and rechecked settings
Replaced filter filter suspecting some type of blockage. not totally blocked but a bit hard to blow through
I have checked for vacuum leaks. none found.
I by-passed all vacuum related accessories during the leak check.
Checked fuel pump pressure = +6 psi. this pump is now 2 years old.
New fuel filter was full at all times until I ran low of gas one evening.
After a refill filter was filled again
Did not suspect any further fuel delivery issues at this point
Still had off idle stalling
Made recommended FSM adjustments with no better results

I turned to look at the electrical at this point

I checked and adjusted timing
It had moved on me twice and when it was not running right seemed to jump around a lot this would be typical of the #1 SP wire not firing correctly which was one of the bad wires
Checked timing chain and gears - 3 degrees play detected (not enough to place this at fault)
Discovered a burnt ignition wire along with a burnt dist cap pole #1 cylinder
Replaced the dist cap, wire and discovered another ignition wire with a loose end - still trying to find a source that will get me the right wires for a poly.
Replaced Rotor & coil as a PM. - parts are cheap enough so why not?
Replaced spark plugs as well. 2 were not firing - equated to the ones that had the bad wires
Checked distributor itself.
Mechanical weights are free
Vacuum advance is good and holds vacuum

I have not done any electronic diag's on the guts itself though

I have not yet checked grounding issues since I am not convinced this is the problem.
BUT I will do that though tonight as suggested here.

Anyone who has suggested I check is right that I should do this regardless of the time that has elapsed since I had everything apart.
It may turn out to be a loose screw. in the engine or my head ") LOL!

When I tore the front clip off a few years back now I cleaned all ground contact points.
Replaced all electrical related wiring for the engine during the rebuild
Not to say that I do not have the ground issue still

Finally, an interesting clue to all of this is that on Sunday when we went to the Simcoe car show the car wanted to stall every time I touched the gas.

I drove it about 10 miles doing this and was about to turn around for home.
I popped the hood and fiddled with the ignition wiring, wriggled the wiring to the ECU and distributor.
Got back in and it ran much better the remaining 40+ miles there and back.
In fact it pulled away from a stop really well no stumble detected at all.
The next morning the issue was back but not nearly like it was on the Sunday.
Checked fuel filter and it was nearly empty so I refocused on the fuel delivery
( I had filled up along the way home)

For now I have to deal with the flooding fuel issue I caused for myself then look at the electrical portion again.

I'm confident it will be fixed and it will probably something silly like the extra keys on the ashtray were shorting out the cigarette light when I turned the corner

Keep the suggestions coming. I hope this helps everyone understand what is going on here.

If the carb is apart again, try blowing through all passages. Maybe a clogged circuit, I find a coffee stir straw or cocktail straw works good for this... and a cigar makes it a visual test.

By your description that wiggling the harness at the ECU cleared things up for a bit makes me wonder if you have trouble there... a very thin wire or guitar string might be used as a probe to sneak around the connector (it will be a PITA to set up) and you could Voltage Drop the circuits to the ECU and also the block and chassis grounds... quick and effective if there is resistance at the time of the test.

Sorry if I get a little punchy... long shift at work, I get that way worse as the week drags on.

I wish you had something else in your description that spoke to me... how old is your gas?

 

[mr. fix it]

Ok
Update after stepping back and thinking this all through

I tested the fuel pump and it failed the test 2 psi tops...

I had purchased a replacement today so switched it out

Also tackled the flooding issue
Found a pice of fuel line had broken off and lodged itself in the needle n seat
I changed the fuel line pieces attached to the filter

To top it off I disassembled the carb to trace my steps and discovered that I had installed the accelerator pump check ball into the metering valve port by mistake reassembled the carb
Reset the float level

End result?
A engine that idles nearly perfectly and pulls off the line and accelerates really well
Actually the gas is fresh as well 91 octane

It still has a slight mid range issue but so slight that I can live with it

I still have a few electrical checks to do but overall I think I can close the books on this issue
I will diagnose the electrical connection to the ECU & Distributor

Thanks for the encouraging replies and suggestions to check the fuel related items

 

[MarPar]

glad to hear the old gal is ok, Tommy!