[gto4evr]

I've been chasing a problem awhile now that seemed to get worse and worse and am looking for some opinions on where to restart the chase here.

Motor was a fresh rebuild in 2007, nothing crazy, just stock stuff with I think the middle of the road cam from summit. currently has 5000 miles on it. (and no issues for the past 14 years like this)

69 400 4bbl, 4spd, with points and a quadrajet, everything is stock. only run the ethanol free 90 octane gas in it.

The cold start issue isn't the "10 degrees outside, badly adjusted choke issue". it's basically not starting on the first startup of the day and it can be 80 degrees out. it cranks over fine, it just won't catch or pop, like it's got no spark. Eventually I flood it in frustration, then finally a few pops, then it'll fire. (we're talking literally 5 minutes of on and off cranking so the starter doesn't melt) Once it's running, the thing runs like a top. smooth and happy, and any restart after it's initial run and it pops off immediately, but after sitting in a parking lot all day at work, once I come back out, same issue again. it just refuses to start "cold"

I only get one shot at trying anything on it each day but here's what I've chased so far:

points are right on at 30 dwell, timing is at 12 and will go out to 24 once running and the advance kicks in.

I've put a timing light on #1 and I see it flashing while I'm cranking so it's getting spark.

choke snaps closed when I twist the linkage and the accelerator pump is squirting in a shot of gas so everything looks fine at the carb. Once it's finally running, the choke behaves normally,

I pulled all the plugs yesterday and did a compression check, all 8 cylinders are 175-180 psi.

I'm at a loss here as to what to try next. I don't see how the points or condenser or coil could be the issue as I can see the timing light flashing while I'm cranking.

one thing a friend mentioned is possible stretched timing chain? It really doesn't want to run with anything less than 12 degrees, but I tried increasing it up through 15 and still didn't start the next morning. I can't believe that chain could stretch already at 5k miles,, but also know that anything made today is crap quality compared to 50 years ago.

so, can a weak spark still flash a timing light and maybe something like a condenser or a coil? but then why does it run perfect afterwards for as long as I want, then fails again after an 8 hr cool down.?

I'm at a loss on this. It's killed my interest in driving the car and summer's slipping away already. any opinions on where I should go from here are greatly appreciated!

[HoneyHush]

What kind of carb is on your engine? It could be leaking all of the fuel out of it. It’ll have some in a pump shot but the wells could be empty.

[PunchT37]

What do the plugs look like? Brand?

[Cliff R]

Empty carb or not it should ROAR to life after 1 or 2 cycles of cranking for a few seconds and pushing on the accl pedal to put a shot of few of fuel into the engine.

Difficult or not able to restart an engine after sitting overnight or really any long periods of time has really NOTHING to do with bottom plugs leaking.

Leaking bottom plugs will cause difficult hot restarts after the vehicle sits for a short period time as they drain the fuel bowl into a hot engine.

The most likely cause of difficult cold starts is weak spark or a bad accl pump. Make sure that you are running and using an ignition bypass wire up from the starter solenoid to the coil.

If the spark is weak it becomes difficult to burn a cold air/fuel mixture even when the choke and accl pump put more in there.

If the accl pump is weak or defective is doesn't add the needed fuel on a cold start even if fuel returns to the bowl. I literally get HUNDREDS of calls about leaking bottom plugs here to the shop and fix 99 percent of them by sending the customer a good accl pump to install. After that move no need to avoid plain old pump gas with up to 10 percent ethanol in it either......FWIW.

Anyhow, below is a copy/paste from my website explaining this issue in more detail:


I get all sorts of calls to the shop, so many these days I can barely get anything else done.

Most of those calls are for parts and/or tech support. I also get a LOT of calls about the fuel bowl draining down from "leaking bottom plugs" and folks having to pour gas into the carb/intake get their engines to fire up after the vehicles has sat more than a week or so.

Well right to start with a BIG hand should be slapping you in the side of the head IF you have to dump fuel into the carb to get the engine to fire up and you think it's a leaking bottom plug issue! This is NOT related to leaking bottom plugs. Even if the carb was bone dry from a fresh rebuild it should fill quickly while cranking the engine and a few pats on the throttle should have the accl pump supplying enough fuel so it roars to life instantly.

If you have to crank and crank and crank the engine plus pump the throttle dozens of times without any fuel getting to the engine the bottom plugs have NOTHING to do with your problems.

This doesn't mean they aren't leaking and need attention, it just means that you either have a fuel drain/back issue, fuel delivery issue, or the accl pump just isn't making it (most likely cause). This is why I will ALWAYS recommend installing one of my accl pumps when you call for tech help about this issue. Those "blue" seals showing up in other kits are NOT making it. Mine will not fail in this fuel and has a lifetime warranty.

I'd also add here that despite all the videos on Youtube and long-lengthy responses from "gurus" on the Forums telling you that ALL Q-jets leak at the bottom plugs and they need a ton of "monkey-chit" dapped over them during the rebuild that in most cases they are NOT leaking.

Leaky bottom plugs are actually quite rare after 1968. From 1965 to 1968 if the casting has the pressed in brass cups for rear plugs 100 percent will be leaking. I've never once to date found a set that wasn't. On those same early units leaks are somewhat common at the front pressed in lead plugs as well.

Rochester knew about this issue and started pressing in aluminum plugs and swaging over them by 1969 which for the most part corrected that issue. A few years later they got rid of the lead front plugs and started pressing/swaging in aluminum plugs there as well. They kept getting better at it and leaking plugs in the later carbs are pretty rare.

Even so every single one should get pressure tested and repaired if/as needed. I still see a few leakers in later units. Just had a 1980 Turbo T/A carb in here with one leaking rear plug. The leak was so tiny that it took 140psi of compressed air applied to the rear jet holes for 30 seconds to find it, but a leak is a leak and it got repaired as needed.

This pretty much covers leaking plugs, so keep in mind that the less intrusive you can be to your carburetor the better. I would NOT start pulling plugs out and tapping for screw in plugs without verifying with compressed air that you have a leak right to start with. I'd also add that 9 out of 10 times if you find a small leak at a rear plug a few gentle taps with a small machinist hammer will usually swage the material back out and stop the leak for another 30 years or so. I'd so all this before attacking the casting with a drill, tap, screw in plugs and fuel type epoxy......hope this helps some........Cliff

[Sirrotica]

As Cliff has already suggested, the 12 volt bypass wiring coming from the starter solenoid is imperative for a hotter spark with a points type ignition at cold crank too. Sometimes in older cars someone has deleted this wiring which is imperative for cold starts with points type ignitions. This wiring feeds the points 12 volts only while the starter is engaged, but greatly aids in cold startups.

The wire could have been broken internally during a starter change/engine change, and not be feeding the 12 volts necessary for cold starting to the points.

Some of the later starter solenoids also omitted the bypass wire terminal after HEI started being used in 1975, so there would be no place to hook the wiring to if using the later style starter solenoid. Aftermarket gear reduction starters may also not have any provision to hook up the bypass wire for point style ignitions.

I have to agree with Cliff that the main problem the OP is encountering isn't fuel related, but probably ignition related.

Just a few possibilities I've run across over the years of wrenching on cars, and especially Pontiacs.

[JSchmitz]

Check voltage at the coil while cranking and running. Swap coil and capacitor with known good if you have them available. Also inspect or replace coil wire cap rotor etc. Sand or fine points to clean off corrosion or replace.

[gto4evr]

thanks for the responses! a few answers to the questions above:
carb is a restamped 7029273 so probably started life as a 268 or something similar. the carb's been solid since I put it on about 7 years ago. at one point the acc pump seal failed and I put one of cliff's good ones in to fix it about 4 or 5 years ago

Accelerator pump is putting a solid squirt of fuel down the hole when I twist it for the morning first start test. so the bowls not empty

plugs are AC R45S old stock plugs (1980's vintage with green stripe)

I'll have to chase that wire off the solenoid to confirm it's not broken. I can't for the life of me picture two wires coming off that solenoid tap. nothing's changed in the wiring on the starter since I built the car 14 years ago. one thing I did change was putting an internally regulated alternator on it. from memory, 2 of the 4 wires to the voltage regulator got spliced together, and the two wires up to the alternator, one from the harness for the gauge, and the other coming out of the alternator is grounded to the bracket, but, I don't think the original wiring for the voltage regulator/alternator ever had anything to do with the distributor or starting circuit, correct?

Now you've got me thinking about when I did that vs when this starting issue started. Frustrating thing is that some days it will just catch after a few turns, but not consistent enough and probably only 1 out of 5 times.


So would a weak spark still be enough to flash a timing light?

step one will be to check this bypass wire to make sure that it's even there (can't imagine it wasn't since the car started fine for 12 years), or if it's possibly broken. if the solenoid doesn't have a tap for it, couldn't I simply add the wire to the 12v tap coming from the ignition switch?

would I damage anything short term by just running a jumper wire off the battery to the coil before trying to start it and then pull it off if it starts so the points don't burn up?

[gtohunter]

Run a jumper from battery to coil.

["QUICK-SILVER"]

Originally Posted by gto4evr

Eventually I flood it in frustration

Need to hear more about this!

Is it pumping the gas pedal to flood the engine or holding the gas pedal on the floor to clear flood? One is a lean fuel mix problem and the other a rich fuel mix problem.

If you really have to flood it to fire off.. You do not have weak spark.

Title of this thread says this car is a 69 GTO. This car never had, didn't come with and doesn't need an extra wire from the starter solenoid 'S' terminal to the coil. IGN-1/RUN and IGN-2/CRANK are both under the dash with a single wire from the firewall to the coil.

Won't even try to guess without more info
Clay

[torqhead]

Originally Posted by "QUICK-SILVER"

Need to hear more about this!

Is it pumping the gas pedal to flood the engine or holding the gas pedal on the floor to clear flood? One is a lean fuel mix problem and the other a rich fuel mix problem.

If you really have to flood it to fire off.. You do not have weak spark.

Title of this thread says this car is a 69 GTO. This car never had, didn't come with and doesn't need an extra wire from the starter solenoid 'S' terminal to the coil. IGN-1/RUN and IGN-2/CRANK are both under the dash with a single wire from the firewall to the coil.

Won't even try to guess without more info
Clay

^^^ What Clay said, I own a 69 and there is not a separate wire between starter and ignition for power during start.

[gto4evr]

Originally Posted by "QUICK-SILVER"

Need to hear more about this!

Is it pumping the gas pedal to flood the engine or holding the gas pedal on the floor to clear flood? One is a lean fuel mix problem and the other a rich fuel mix problem.

If you really have to flood it to fire off.. You do not have weak spark.

Title of this thread says this car is a 69 GTO. This car never had, didn't come with and doesn't need an extra wire from the starter solenoid 'S' terminal to the coil. IGN-1/RUN and IGN-2/CRANK are both under the dash with a single wire from the firewall to the coil.

Won't even try to guess without more info
Clay

69 gto all original wiring. solenoid wire on carb is connected and energized

starting procedure:

press pedal once to the floor to give it a shot of gas from acc pump and set the choke. turn key. cranks.....and cranks. stop. press pedal again once thinking a short shot of fuel on acc pump that maybe didn't give it enough gas (I think it is -- when I test the next day with the air cleaner off and my head in the carb as I turn the linkage by hand and I see a solid shot of fuel go in) anyways...crank again...still nothing. no pops, nothing, just like no spark.

Then press the pedal a few times while cranking, at this point I can smell fuel, it's flooding. Hold pedal to the floor while cranking to force butterfly open to clear the flood. an occasional pop. get out, stick a screwdriver down the butterfly to hold it open completely, sit there staring hatred at the car, wait a few minutes, get in, don't touch the pedal and crank. a pop then a few more pops, then it fires up clears out the flood and hums like a top. shut it down, turn the key again and it fires up immediately. now it's the perfect car for anywhere I drive it as long as it's not parked for 8 hrs.


okay, makes sense on that wire, I really don't remember there being two. so, along the same line of thought though, could it be a failure in the ignition switch not pushing it up to 12v during start?

[PunchT37]

Check float level. May be too high. Check float condition also. See if it`s got fuel IN it, making it heavy.

["QUICK-SILVER"]

Cold engine and before you spin it.. Prop the choke wide open and see if it fires off with a pump shot or two. Qjet should in warm weather.

If it works we can go further. Sounding like choke is too rich for ambient temperature, pull-off bad or not adjusted right and possibly mixture screws adjusted lean.
Clay

[HoneyHush]

It is clearly flooded. If the ignition is strong enough to start it after the description of how you start it. The plugs probably need changed but you have to be getting a lot of fuel into the engine before or during trying to start it. The cylinders, intake track and plugs are probably wet. Too much fuel coming from somewhere. The ignition system doesn’t get stronger the more you crank it. The fact that you have to hold the pedal to the floor to start it.....flooded. You have another carb to try on it? Try to spray starting flood at the beginning?

[OG68]

I think Clay may be on to something and to add on to his post, the 69 does have a bypass wire but it is in the dash harness. The black/pink resistance wire (ignition switch terminal E/IGN 1) and the yellow bypass wire (ignition switch terminal D/IGN 2) meet at the firewall plug terminal BY. From there a non resistive single wire (black/pink) goes to the coil.

This may be a simple repair by just adjusting the ignition switch slightly up or down on the column to fully engage the start ignition IGN 2 terminal or the switch may have a burned or corroded IGN2 terminal requiring replacement of the switch.

[steve25]

I have had cases with the points type dizzy which had the wire running from the points under the breaker plate and out of the body loose just about all of its insulation due to dry rot and then short out.

Thisi issue on one motor caused it to cut out intermittently when hot, and on another motor make for no starts .

[torqhead]

Originally Posted by gto4evr

69 gto all original wiring. solenoid wire on carb is connected and energized

starting procedure:

press pedal once to the floor to give it a shot of gas from acc pump and set the choke. turn key. cranks.....and cranks. stop. press pedal again once thinking a short shot of fuel on acc pump that maybe didn't give it enough gas (I think it is -- when I test the next day with the air cleaner off and my head in the carb as I turn the linkage by hand and I see a solid shot of fuel go in) anyways...crank again...still nothing. no pops, nothing, just like no spark.

Then press the pedal a few times while cranking, at this point I can smell fuel, it's flooding. Hold pedal to the floor while cranking to force butterfly open to clear the flood. an occasional pop. get out, stick a screwdriver down the butterfly to hold it open completely, sit there staring hatred at the car, wait a few minutes, get in, don't touch the pedal and crank. a pop then a few more pops, then it fires up clears out the flood and hums like a top. shut it down, turn the key again and it fires up immediately. now it's the perfect car for anywhere I drive it as long as it's not parked for 8 hrs.


okay, makes sense on that wire, I really don't remember there being two. so, along the same line of thought though, could it be a failure in the ignition switch not pushing it up to 12v during start?

Sounds like there is not an ignition spark issue and is simply being flooded with the first full press of the pedal. Choke flap may be too tight, should be adjusted cold.

Next time you try to start it cold, do not press to the floor. Try a 1/4 pedal or less pump, press and release, just enough to set the choke, You could do this under the hood. Then start the car so you're not giving it much fuel and see if it starts. Also look to see how "closed" the choke is, make sure it's not snapped "tightly" closed. When motor start it needs to be able to draw it open slightly, 1/8" to run.

[SRR]

Take a good look at where the coil wire connects. I had a car do this once and it had a hairline crack in it.

[gto4evr]

updates:

okay, got home from work (late for the car show) but couldn't wait to test so we were even more late.

anyways. pulled open the air cleaner, twisted the throttle half turn, the choke closed but not forcefully, but I then pinned it back open with a screwdriver anyways. gas squirted in from the acc pump. I got in, didn't touch the gas pedal and cranked. it cranked 30 seconds without a pop. stopped, tried the key again without touching the gas pedal and it popped over and fired up.

Pulled off the vac line off the choke pull off, that's working properly. plugged it back in and backed out of the garage then took it to the show since I didn't have time to dig the other car out we were supposed to take tonight.

Just got home. popped the hood, opened everything back up and pulled the coil wire off. took a volt meter to the lead from the ignition at the coil and turned the key to the on position. I'm seeing 7.5 volts. Had my son crank the car over while standing there and the voltage goes up to 8.8 steady. when he lets off the key I see a brief spike in the volt meter to 12v. it's a cheap ass Harbor Freight voltmeter so no idea if it's refresh rate is quick enough to show true voltage. Anyways, of course, warm, the car starts perfect every time I try now so can't do anything til tomorrow after work again.

also, checked coil for cracks, and see none, and the wire between the coil and the distributor, I replaced that with a new one last year when I first started battling this issue. didn't see any cracks in the one I took out. (car only got maybe 50 miles in it last year due to covid and lack of shows) points were replaced at that time as well with no improvement. (and the ones I took out looked fine)

so tomorrow's test will be adding a 12v jumper from the battery directly to the coil to prove out whether that 8.8 is just a crap reading from an HF voltmeter, and I'll follow the same carb procedure of a small quick squirt of ACC pump with butterfly held open.

[ID67goat]

Originally Posted by gto4evr

one thing a friend mentioned is possible stretched timing chain? It really doesn't want to run with anything less than 12 degrees, but I tried increasing it up through 15 and still didn't start the next morning. I can't believe that chain could stretch already at 5k miles,, but also know that anything made today is crap quality compared to 50 years ago.

This also seems strange....it should run with no advance. Have you verified balancer at TDC so you really know if your timing is set correctly?