All Small Six Unable to get my 68 L6 started!

[RO117]

Hello,

I am at my wits end on trying to get my mustang to start. This is my first timeowning a classic car and have been consuming as much knowledge as possible. It sat for 2 years from the PO, and but before he daily drove it and he always had to use starting fluid to start it up.

Since its been in my possession, I have replaced much of the electrical system:
Battery, all cables to/from solenoid, starter, starter solenoid, and 1-wire alternator, spark plugs + wires, distributor cap, and rotor.
From PO, it has a 22gallon fuel tank and Petronix Ignitor 2. I confirmed that it receives 12v during start. I confirmed with a inline spark tester that each cylinder is getting spark.

I have checked timing with #1 piston at TDC, and that the rotor is pointing at #1 at 12* BTDC, but there is a chance I was doing this wrong. I had my friend put his thumb over the spark plug hole to confirm that there was air coming out, and putting a stick in for it to be pushed out at the highest point. My next step is to get a piston stop tool to confirm, but please let me know if this is correct.

When cranking the engine, carburetor will backfire, and some popping from the exhaust. I also confirmed fuel is coming into the carb by pulling on the throttle. Messing around with advancing/retarding the distributor, one way will cause only popping and no backfire, and the other way will only cause backfire from carb and no popping from exhaust.

At this point, I believe the timing or the Autolite 1100 is the issue. Please let me know your thoughts!

Pictures:

https://imgur.com/a/hhynWoa

 

[Frank]

Hello,

I am at my wits end on trying to get my mustang to start. This is my first time owning a classic car and have been consuming as much knowledge as possible. It sat for 2 years from the PO, and but before he daily drove it and he always had to use starting fluid to start it up.

Since its been in my possession, I have replaced much of the electrical system:
Battery, all cables to/from solenoid, starter, starter solenoid, and 1-wire alternator, spark plugs + wires, distributor cap, and rotor.
From PO, it has a 22gallon fuel tank and Petronix Ignitor 2. I confirmed that it receives 12v during start. I confirmed with a inline spark tester that each cylinder is getting spark.

I have checked timing with #1 piston at TDC, and that the rotor is pointing at #1 at 12* BTDC, but there is a chance I was doing this wrong. I had my friend put his thumb over the spark plug hole to confirm that there was air coming out, and putting a stick in for it to be pushed out at the highest point. My next step is to get a piston stop tool to confirm, but please let me know if this is correct.

When cranking the engine, carburetor will backfire, and some popping from the exhaust. I also confirmed fuel is coming into the carb by pulling on the throttle. Messing around with advancing/retarding the distributor, one way will cause only popping and no backfire, and the other way will only cause backfire from carb and no popping from exhaust.

At this point, I believe the timing or the Autolite 1100 is the issue. Please let me know your thoughts!

You've verified fuel to the engine. Was it running before, or has the issue happened after a distributor alteration? Verify all 6 wires are in order, 1-5-3-6-2-4- clockwise. If no distributor removal since it was last running, redoing the phasing test is not necessary, your method of checking it sounded right. It may be the Pertronix unit.

Verify the distributor is grounded. It's rare but has happened to me twice, once 40 years ago and again just last week: the points lost ground. The points or Pertronix have to be grounded. The points (or module) ground through the breaker plate to the distributor body to the engine block. Over decades the contact can become weak, hard as that is to imagine, with it bolted into the block. Use a jumper wire with aligator clips or a jumper cable, fasten to the distributor and a good ground (batt. -) . If it starts, fabricate a permanent ground to the distributor, it's a good idea anyway. I put them on the vacuum advance can, or any good screw on the distributor body, to a good block ground.

Just FYI, if you do find the rotor pointing at another tower, including 180* off (pointing @ #6) the wires can be pulled and replaced in the cap with #1 over the rotor, it's not necessary to pull the distributor to re-phase it. It does not matter where #1 wire is plugged into the cap.

Just some thoughts, but it does sound like an ignition timing, ignition module, or ignition ground issue. Or a very slim chance the timing chain has jumped time.

 

[DON]

Another angle,
You stated the Po had to use starting fluid to start it, then you said it sat for 2 yrs, correct?
I would try putting some fresh gas down the carb. Less than 1/4 cup, maybe half. And see if it fires. I would hold it wide open when cranking but get ready to release throttle if it fires. Even if the accelerator pump is squirting gas, you might have some jets plugged. Do you know what gas the po used? If it was ethonal free, if it was, it shouldn’t be a problem, if it was reg/ med or premium gas, I would drain it all out and start over with fresh and probably carb needs cleaning.
I use nothing but ethanol free in my stangs, lawn mower and blower—any thing that sits. I don’t have any problems other than bowls drying up and new gas has to be pumped in before it will fire.

 

[RO117]

You've verified fuel to the engine. Was it running before, or has the issue happened after a distributor alteration? Verify all 6 wires are in order, 1-5-3-6-2-4- clockwise. If no distributor removal since it was last running, redoing the phasing test is not necessary, your method of checking it sounded right. It may be the Pertronix unit.

Verify the distributor is grounded. It's rare but has happened to me twice, once 40 years ago and again just last week: the points lost ground. The points or Pertronix have to be grounded. The points (or module) ground through the breaker plate to the distributor body to the engine block. Over decades the contact can become weak, hard as that is to imagine, with it bolted into the block. Use a jumper wire with aligator clips or a jumper cable, fasten to the distributor and a good ground (batt. -) . If it starts, fabricate a permanent ground to the distributor, it's a good idea anyway. I put them on the vacuum advance can, or any good screw on the distributor body, to a good block ground.

Just FYI, if you do find the rotor pointing at another tower, including 180* off (pointing @ #6) the wires can be pulled and replaced in the cap with #1 over the rotor, it's not necessary to pull the distributor to re-phase it. It does not matter where #1 wire is plugged into the cap.

Just some thoughts, but it does sound like an ignition timing, ignition module, or ignition ground issue. Or a very slim chance the timing chain has jumped time.

Frank,

It was not running before. I do remember looking at the grounds inside the distributor and thinking they were looking a bit iffy, so I'll definitely have to do as you were saying! Another thing I noticed, and I'm not sure this is normal, but am I suppose to get ground at the ignition coil? When I put my test lead on positive and negative of the ignition coil, it doesn't read any voltage; however, putting the ground test lead on a good ground will show 12v at coil.

 

[awasson]

The trouble you’ve described (backfiring through the carb) sounds to me like the distributor is 180 degrees out (or the firing order is backwards; easy to do). The piston will be at TDC for the compression (firing stroke) as well as the exhaust stroke so if you’ve pulled the distributor it is easy to put the distributor in 180 out. I don’t want to brag but putting distributors in 180 out is kind of my super power.

Everything else you’ve described sounds like the engine should happily fire up and run. I hope it’s something simple.

 

[TrickSix]

These cars are old and have been through a lot. Things wear out and pevious owners make dubious repairs and swap parts. You should verify that the carb, distributor, vacuum lines, etc are what they are supposed to be, and are hooked up right. Because something is wrong. If the engne is mechanically sound (and it's not 20 below) you shouldn't need starting fluid to make it fire up. If I've been driving mine lately enough so the float bowl is full of gas, but not recently enough to be a warm start, it will still fire up right now! Some pictures of your engine bay may provide a clue to someone as well.

 

[Frank]

Frank,

It was not running before. I do remember looking at the grounds inside the distributor and thinking they were looking a bit iffy, so I'll definitely have to do as you were saying! Another thing I noticed, and I'm not sure this is normal, but am I suppose to get ground at the ignition coil? When I put my test lead on positive and negative of the ignition coil, it doesn't read any voltage; however, putting the ground test lead on a good ground will show 12v at coil.

It was not running- ok. Truthfully, I'd go with fresh gas first, if you haven't already. The fact that PO had to use ether is not a good indicator. Before going too deep into the ignition, a compression test would clarify correct valve timing and engine condition. Valuable to avoid guess-repairs and wasting time/$ on systems that were already ok.
If you're not sure of the procedure, let us know. The test gauge may be on the loaner-tool list at your local auto parts store, but IDK for sure.

Your coil seems fine, that's farther down the list of troubleshooting. Since it was backfiring, you have at least some spark. New gas and check compression, the picture will be clearer where to proceed from there.

 

[RO117]

I updated the post to include pictures (these are before pictures). Hopefully it provides some insight!

 

[Frank]

I updated the post to include pictures (these are before pictures). Hopefully it provides some insight!

The plug wires are in the right order. This won't help it start, but the plug on the inner vacuum advance nipple needs to be removed. That needs to be open to atmosphere for advance to function. Use a 3" piece of vacuum line and loop it over facing down to keep the inner port clean. That's an emissions port and should not be used, but cant be capped.

 

[RO117]

The plug wires are in the right order. This won't help it start, but the plug on the inner vacuum advance nipple needs to be removed. That needs to be open to atmosphere for advance to function. Use a 3" piece of vacuum line and loop it over facing down to keep the inner port clean. That's an emissions port and should not be used, but cant be capped.

Thanks for the tip! Someone had pointed out that my vacuum lines don't look right. I did notice today that port was capped off and was planning to fix that. My other question is though, should I be following this diagram or is it already hooked up correctly besides the capped nipple?

 

[TrickSix]

Yea, something in your distributor vacuum line system doesn't add up. I've got a '66, so I don't know much about those newfangled multiple vacuum line systems. But the distributor is set up for two lines, and there's just the one going there through that temp switch. People run those double vacuum diaphragm distributors with just one line all the time though, so that alone might not be behind your starting problem. For a cheap thing to try a while to eliminate variables, I'd buy a few feet of 3/16" (or whatever) id rubber fuel line and run from the carb straight to the distributor, bypassing that switch and any possible problems on that line.

On a second subject, most of the pics show a carb that looks used, but correct for '68, without a spark control valve. The last picture (with the valve cover off) has what looks like a new carburetor. But the pic is the wrong side to confirm if a SCV is there or not. Is there a new carb on the engine now? Parts suppliers have been known to get this detail wrong.

 

[RO117]

Yea, something in your distributor vacuum line system doesn't add up. I've got a '66, so I don't know much about those newfangled multiple vacuum line systems. But the distributor is set up for two lines, and there's just the one going there through that temp switch. People run those double vacuum diaphragm distributors with just one line all the time though, so that alone might not be behind your starting problem. For a cheap thing to try a while to eliminate variables, I'd buy a few feet of 3/16" (or whatever) id rubber fuel line and run from the carb straight to the distributor, bypassing that switch and any possible problems on that line.

On a second subject, most of the pics show a carb that looks used, but correct for '68, without a spark control valve. The last picture (with the valve cover off) has what looks like a new carburetor. But the pic is the wrong side to confirm if a SCV is there or not. Is there a new carb on the engine now? Parts suppliers have been known to get this detail wrong.

Yup, you're correct about the SCV carb! I know its wrong but I was using it temporarily since after rebuilding the old one, it still leaks badly from the dashpot even prior to rebuild. I'm thinking its the steel plate that goes around the dashpot or possibly the gouge in the metal where it seals. I'm prob gonna use some parts from the new carb as a donor and see if that fixes it.

 

[Frank]

Thanks for the tip! Someone had pointed out that my vacuum lines don't look right. I did notice today that port was capped off and was planning to fix that. My other question is though, should I be following this diagram or is it already hooked up correctly besides the capped nipple?

The single line to the outboard port on the advance can should go directly to the carburetor, ported vacuum. You can remove the rest. I was struggling to see the correct port on the carb for this line, and am not hands-on familiar with it.

 

[Frank]

Yea, something in your distributor vacuum line system doesn't add up. I've got a '66, so I don't know much about those newfangled multiple vacuum line systems. But the distributor is set up for two lines, and there's just the one going there through that temp switch. People run those double vacuum diaphragm distributors with just one line all the time though, so that alone might not be behind your starting problem. For a cheap thing to try a while to eliminate variables, I'd buy a few feet of 3/16" (or whatever) id rubber fuel line and run from the carb straight to the distributor, bypassing that switch and any possible problems on that line.

On a second subject, most of the pics show a carb that looks used, but correct for '68, without a spark control valve. The last picture (with the valve cover off) has what looks like a new carburetor. But the pic is the wrong side to confirm if a SCV is there or not. Is there a new carb on the engine now? Parts suppliers have been known to get this detail wrong.

Where is his ported vacuum nipple on that carb?

 

[TrickSix]

Where is his ported vacuum nipple on that carb?

Which carb? You can see it in the pics of the used looking carb, on the passenger side right next to the empty SCV socket, which is normal for the '68 carbs. The one pic of the new carb doesn't show that side, but there's no reason to think the vacuum port isn't in the normal place. I wonder if the parts supplier got the right model 1100 with no SCV, that version is rare, and that one pic doesn't show it.

 

[DON]

I’m having a hard time viewing the pics
Trying to zoom in and it’s jumping around

 

[philford]

I suggest checking the compression as well. if it has low compression burned valves, maybe a bad piston then you might as well know sooner than later.

i hooked a small LED across my coil primary, then it blinks when cranking and blinks fast , which looks like a steady lamp when running. If I suspect issues with the engine not getting a spark the first thing I want to know is if the primary coil has a pulse, this way I can just look down at my LED. I know if the primary is not pulsing if its out and I can do that from the driver's seat just by looking. If you do this, be careful those wires cant; get grounded to body or it'll kill the ignition pulse.
I pulled my coil out and gave all the wires a good cleaning at the same time. cost of that is only a dollar or so for a small bulb or an LED. My van is newer so it has an ignition module , sometimes they fail, If that happens.. I'll see I have no ignition pulse so its mostly just a fast way for me to monitor that and it's info , I'd like to know if it wont start up. that was easy and now I have the answer just by looking at it. I just ran it through the firewall and under the dash where I can get to it to look easily otherwise it can be ignored.



it sounds like it wouldn't hurt to remove the carb give it a good cleaning and blow out any holes and jets etc. keep track of where any adjustment screws are by bottoming them gently and note the number of turns. I'd replace the needle valve check the float check the float level.

other guys here know these ford carbs better.. there is probably a kit with the needle and seat and any gaskets etc. and you are getting help with the hoses.. If you can access an ultrasonic cleaner they are good for cleaning carbs.

if compression is really low in any of the cylinders don't play with the carb because you have bigger fish to fry.

a sign of a worn engine is when you shut it off, if it loses compression it may seem to wind down to a stop rather then just shutting off. that can make a car hard starting but with quickstart you may be able to get it running warmed up and then it may start easily until its cold again.
if continuously spraying quick start in keeps it running but without it it dies you might have fuel starvation.. plugged jets maybe or weak fuel delivery. you can put the fuel hose in a can give it a crank you should see some quantity of fuel, don't start a fire. if its a mechanical pump maybe you have a torn diaphragm and weak fuel delivery, for example.

in a situation like this I like to replace the plugs, then they are new and clean,, after running it a whole you can pull the plugs, take a pic see if they are all black or if the color indicates a pretty normal air fuel mix. (tan) if they are white it might mean you are fuel starved.. see what they look like when you pull them.

watch your water level in the rad, if water seems to be disappearing or if you see water in the oil or oil in the water or froth on the filler cap, or antifreeze smell or abnormal dripping from the tailpipe accompanied by a sweet smell those are head gasket issue signs. probably not that but things to watch for when assessing a new to you old car.

if you suspect bad gas Id just sipon it off to a jerry can have a look see if you see any rust or water or anything funny, you can always dump the gas back in at a later date or maybe filter it and dump it in some other car.. if it looks ok so it doesn't cost or leave you stuck with a jerry can of stinky fuel to get rid of.

I'd fill a jerry can with good gas, maybe add some fuel conditioner, give it a shake and dump that in. getting some fresh fuel in won't hurt things. If you have a car sitting you can always still just siphon some and switch the fuel around at no real cost. just be careful doing it.

you might find you have a rusty tank and bits of rust inthe gas and that will plug the carb. you might temporarily install an inline fuel filter to monitor and see if it seems to get dirty.

if I bought a car like that Id probably dump a litre of sea foam in the oil run it a little while and then change the oil, if you take it apart it'll be less dirty inside. if you don't take it apart it'll help clean some gunk out of the sump anyway and the oil will stay cleaner.. I wouldn't do that religiously to a well running and maintained car but if I bought an old car that's been out of use, then I would. If I knew I was going to open up an engine I'd rather it not have stinky old oil to go spend my time mucking around with. I'd use the cheapest brand I can find for that.

if compression is low then focus on that if not then focus on the carb and ignition timing needs to be set right.

to get your timing close to right so you can start it up I think you should view this video, he gives a good demo on how to static time an engine with an old school distributor.

once running you can follow a manual to fine tune it per the manual, but that's how you can get non running engine close enough to start so you aren't goofing with turning it and experimenting and making it backfire.

I think following this video could help you sort out the distributor position.. It won't actually hurt to give the distributor some cleaning maybe a bit of lube on the lobe and maybe clean and lightly lube the advance mechanism make sure its not stuck.

on some cars there is a shaft O ring and you don't want oil coming up into the distributor due to old orings and stuff but maybe pick a better time to get into that stuff. you probably don't need to go disassembling it to get it running at least.. what you don't want is to create a situation where you mucked with all sorts of stuff and now have two or three reasons why your car wont start - all at once!

 

[RO117]

Hey all!

Just a little update here. I finally got around to the compression test and here are the results:
Dry (Throttle wide open, ignition disabled)
1 - 115, 2 - 145, 3 - 145, 4 - 150, 5 - 155, 6 - 135
Wet (Poured two capfuls of Marvel oil down the cylinders)
1 - 125, 2 - 150, 3 - 145, 4 - 155, 5 - 160, 6 - 140

With cylinder 1 being much lower than the rest, how bad is this?

On another note, I used a piston stop to find timing again, making two marks CW and CCW, and found that the white timing mark that was already on the balancer was exactly in between the two marks. I also stabbed the distributor to make sure it wasn't off a tooth and pointed to #1 at 12* mark again to make sure. While bumping the starter, I noted that the timing mark never lines up or even close with the 12* mark when the rotor is pointing at #1. Is it suppose to or is my thinking wrong? In any event, I am looking to replace the chain and sprockets next. Please let me know your thoughts!

 

[RO117]

Oops duplicate.

 

[awasson]

Your rotor should be very close to #1 when the timing mark is between 0 and +12. That was my concern when I suggested that the distributor is 180 out. Backfiring through the carb isn’t always conclusive but it is a giveaway.

Your low compression issue sounds like a valve issue. Either the valves aren’t sealing or they aren’t fully closing. If you’ve had the head off (or someone has) and it was shaved or the deck was, it might be that the pushrods are too long by a hair. Hard to say without being there. You could pull the pushrods and then use compressed air with a gauge to see if they seal a wet cylinder.