Updated 289 with starting issues

I have a 1966 Mustang with a 289. Edelbrock carb/MSD ignition/electric choke. I have a very difficult time getting it started. It cranks and cranks. Should I get it started it runs very well. The car has been restored. It is not a show car but from 15ft it looks great. I have replaced the battery, spark plugs, starter. Spark plug wire resistance measure ok. It is strange that it runs well once started. No sputtering or stalling. The starting issues are not dependent on temperature. Looking for suggestions

1 Like

Same problem when the engine is warm or cold? Just turned off or sitting over night?

1 Like

What exactly do you do to start it? Just turn the key? Or…what?

Has the mechanical fuel pump been replaced?

1 Like

Is that an ethanol tolerant carb?

Tester

1 Like

The Edelbrock carb is a revised version of the Carter AFB. The tooling was purchased by Edelbrock decades ago. They are compatible with E10.

1 Like

Welcome to the CTC Quig! For those who know me, Quig is my lifelong buddy and UMASS college roommate. Hope we can help him figure this one out.

2 Likes

Welcome to the forum Mr Quig! I have an early 70’s ford truck w/302 & Autolite carb. Over the years when it refused to start these were the problems

  • Starter solenoid failed or intermittent. This is the part that bolts to the firewall. It powers the coil differently in start mode than in run mode. Done b/c start mode requires higher voltages.

  • Starter solenoid ok, but its ground screw worked loose. The ground is provided by its attachment to the firewall.

  • Carb leaked gasoline into intake manifold via power valve. Caused flooded condition , most noticeable on warm starts. During cranking engine sounds like it has lost compression (but it hasn’t). Try holding the accel pedal all the way to the floor when starting.

  • If none of above, suggest to measure engine compression, as that could cause this symptom.

  • One more, carb fuel bowl empty b/c of problem w/carb inlet valve. Check level of fuel in fuel bowl. Good opportunity to also verify choke plate is behaving.

One way to check for some of the carb issues is to remove the air cleaner, hold open the choke, and look down the carb while pumping the gas (cold engine). If no gas squirts out you may have the power valve or inlet valve problem George mentions above. Or, if your last drive was long and hot, the fuel might have boiled out of the carb after shut down.

Lots of questions, we look forward to your answers.

On some of those fancy new carbs the fuel level is visible through a little window. If OP’s has that feature, good place to look as a start.

Welcome to the forum…

MSD distributor?? points or electronic?? Or MSD 6AL ignition box?? Lots of variables when you say MSD ignition… Please more detail on it… Is it a single or dual vacuum port distributor??

The 1st 2 questions (Texases/Mustangman) really need to be answered before we can go much further…

Looking forward to finding out what the issue is…

One thing you can do is spray some starter/brake fluid in the carb and see if it starts right up…

Check your ignition timing at idle, make sure not way advanced or locked out, if dual vacuum port distributor then make sure the correct vacuum lines are going to the correct ports, one retards the ignition when starting/idle, the other advances as normal…

Again, lots of questions need to be answered… lol

You need the factory wiring diagram. Examine how the ignition switch is wired from the factory. You may have two separate ignition circuits, one for starting and one for running. One uses a ballast resistor, the other does not.

Try this. Get in, push the gas pedal about half way to three fourths the way to the floor and let up. Turn the key to start and if it doesn’t start right away, release the key to see if it tries to start just as you release it. If that happens, ten you are not getting ignition voltage during the start cycle. You will need to consult with MSD on how to wire it for that.

1st let me say thanks to everyone for your interest and help.

I want to make certain I am clear. Once the car is running it runs really well. No stalls or sputters. This is why it is so confusing for me.

KEITH who replied just a couple of hours ago said something interesting. I have noticed that every once in a while when I try to start the car and as I release from the START position engine actually fires. Sometimes it has even started. I have tried to turn the key to a position between RUN and START to get this to happen but I have not been successful.

@Mustangman I just turn the key. If there is another process I am all ears.

@George_San_Jose1 Since it runs so well once I get it started I have to assume the fuel pump is working properly. I also replace a small section of the tubing near the carb with clear hose. There is gas getting to the carb. I cannot say it is getting directed properly but it is getting to the carb. I can smell the fuel after cranking a few times.

However your 1st comment is probably in line with @keith. I was not aware that there are differences between START and RUN.

This is not a modern car. Slowly depress the gas pedal as you crank the engine. If it coughs a bit when it starts, pump the pedal once before cranking and squeezing.

I am going to assume that the MSD was installed correctly without resistors. Not sure the 66 ever had a ballast resistor. If the MSD gets 12 volts when cranking and 13.5 or so when running, all is good.

1 Like

Make sure there’s a good connection at this wire

Tester

I think he means that the starter is bringing down the Voltage in the car to the point where the ignition is too weak to ignite the gasoline. When the starter is not engaged, the Voltage is high enough to have proper igintion and it runs fine. If it was a manual transmission, you could roll start it without using the starter and it should start fine. So you have some kind of ignition trouble where the ignition isn’t able to function properly down at 8 Volts which is where the battery is when cranking. Maybe there is a resistor that is supposed to be bypassed during cranking that isn’t. Adding a jump starter should make it start better.

Open the throttle, engine don’t start easy with the throttle set at 600 rpm idle speed.

If the engine is cold, press the accelerator once to set the choke and fast idle cam, then crank the engine. If the engine is warm/hot, hold the accelerator at 1/4 throttle while cranking the engine to clear out the fumes from the intake manifold.

2 Likes

That’s all I do on my 302 equipped truck, starts right up with 5-10 seconds of cranking. I don’t need to mess with the accel pedal at all until after the engine pops and starts. Provided I drove the truck the day before. Yours is a different make/model/vintage/& engine, so can’t speak to your configuration exactly. I don’t recall having to mess with the accel pedal to get my 62 Ford 6 banger to start either, but I did have to mess with its manual choke. Truck has automatic choke.

I expect you find a lot of good ideas from the posters above. suggest those are where to start your (or your shop’s) experiments. Suggest to put the compression testing toward the end of the sequence, b/c that’s not the likely cause unless you have reason to believe there’s a compression problem.

I think if I had this problem and none of the above ideas panned out, I’d challenge the idea that the engine runs fine once started. So the next step, I’d measure the intake manifold vacuum at idle (presuming you can eventually start it.) It should hold steady in the 17-22 in range. If it does, I’d check the timing chain situation, as the timing chain may have stretched enough to throw the valve timing out of whack. There’s a way to do this fairly easily, your shop will know, or ask here. Out of spec valve timing can cause a hard to start problem, but is more forgiving once the engine starts. .

Does is start ok everytime, if you drove it the day before? If so, that’s a big clue.

You need to depress the gas pedal about half to 3/4 to the floor. When you shut down from warm, the throttle linkage is down on the lowest level of the choke link. The choke link is stepped and because of this, even after the engine cools down, the choke is held open by the throttle link.

Stepping on the gas pedal will release the choke link so the choke can close and squirts a little gas into the manifold for the engine to start with.

I always had the best luck with press and release, then turn the key. They usually start right up. Holding the gas pedal down or pumping it can result in a flooded engine that will not start until it gets cleared, which can take some time if you don’t know how to manually clear it.

That wont be successful as you will be between two contacts, not connecting to either, in other words, dead circuit (open circuit). Because the start position and the on/run position on the ignition switch are two separate contacts, you have to have two ignition circuits. On some switches, the two circuits are internally connected so only one ignition wire out of the ignition switch. There are other wires like acc, start etc.

If you only have one ignition wire, it is possible that you might need a new ignition switch, but you want to verify that you don’t have spark during the start cycle. If you have a spare spark plug laying around, you can check for this by pulling one spark plug wire off one spark plug and connecting it to the spare plug. Make sure the spare plug is well grounded against the engine, then turn the key to the start position and see if there is a visible spark while the starter motor is running.

I got the car started last night. It took many cranks. I tried so many different accelerated pedal things i cannot say what made it start. Bottom line is that i don’t have a solution. I drove it for an hour without issue. Smooth. I shut it off and was able to restart on the 1st crank. Almost immediately. I used a jumper pack to support the battery during cranking. I have done this many times to get it started. It is certainly a clue to the problem in my opinion.