I just recently got a 1971 Mustang with a 351 Cleveland 2V. I am working on starting it. It turns over fine, and it sounds like it almost starts, but then it doesnt. I have new gas, new fuel pump, and gas is getting to the carb, new fuel filter, new points, condensor, plugs, and wires. The wires are all in the correct spots. I have a wiring diagram. Now the Carb backfires when I am turning it over. Why? Is my timing off? How do you change the timing? I hve the points style distributor. I thought you just turned it, but Its clamped down... I have some mechanical skill. But I am new to this distributors and carbs. Thanks
Hello. If you are saying that, you turn the key to the start position, it cranks and sounds like it started, you release the key, and the motor dies instantly, then more than likely, your tach went south on you. If you go behind the instrument cluster and look at the back of the tach, you will see two wires coming out of the back of the tach that have bullet connectors a few inches back from the tach. Unplug those two wires and plug the two wires that go back to the harness together. Not the two short wires that are still hanging out of the back of the tach, but the other two that those wires were plugged into. Your problem, if it is doing what I asked you if it was doing, has something to do with the resistor wire that goes from the 'on' position of the ignition switch through the tach and eventually out to the coil. It could be the wire itself, or possibly the ignition switch, but that problem is almost always a dead tach. Hope that helps.
< Message edited by VeronicaScz -- 6/8/2007 11:51:08 PM >
To adjust timing you need a 1/2 " wrench. Loosen the bolt under the distributor where it goes into the block. Mark it on the shaft and on the block before you move it so you know where you started. It can also backfire though the carb if it is flooded.
Sounds like your initial timing is 180 out. Set your intital (static) timing and see if you can get it to start, then use a timing light to get it even closer.
Sounds like your initial timing is 180 out. Set your intital (static) timing and see if you can get it to start, then use a timing light to get it even closer.
Hi again. He won't be able to get it to start if his tach is dead. It sounds like what he is calling backfiring is something that started to happen only after several failed attempts to start the car. If that is in fact what happened, it isn't a distributor or timing problem.It's probably the result of all that gas he said was getting to the carb starting to puddle up in his intake. But, you never know.
Sounds like your initial timing is 180 out. Set your intital (static) timing and see if you can get it to start, then use a timing light to get it even closer.
Hi again. He won't be able to get it to start if his tach is dead. It sounds like what he is calling backfiring is something that started to happen only after several failed attempts to start the car. If that is in fact what happened, it isn't a distributor or timing problem.It's probably the result of all that gas he said was getting to the carb starting to puddle up in his intake. But, you never know.
He doesn't mention that he even has a tach. What does a tach have to do with the engine not starting?
Run a temporary jumper from the battery to the positive side of the coil for troubleshooting. Don't leave it on for too long of a time. As to an open circuit, there is the resistance wire and a fuse as well that give the same symptoms as an open tach (if it exists). Jim
Hi again. He didn't say specifically "I have a factory tach" but the problem that he describes, if I'm understanding what he's trying to say, just screams " I have a factory tach". What that has to do with starting the car is that the factory tachs were inline on the resistor wire. Whe the key is in the start position, that isn't going through the tach, and the car sounds like it started, because it did. But, as soon as you release the key to the on position, the tach is upstream from the coil on the ignition circuit. When the tach dies, it's like tripping a circuit breaker. So, the car sounds like it started, you release the key, it dies instantly. Almost like somebody threw a switch. But, as I said, I could be completely misunderstanding what he is trying to say. His description is a bit vague.
< Message edited by VeronicaScz -- 6/9/2007 2:53:31 PM >
Hi again. He didn't say specifically "I have a factory tach" but the problem that he describes, if I'm understanding what he's trying to say, just screams " I have a factory tach". What that has to do with starting the car is that the factory tachs were inline on the resistor wire. Whe the key is in the start position, that isn't going through the tach, and the car sounds like it started, because it did. But, as soon as you release the key to the on position, the tach is upstream from the coil on the ignition circuit. When the tach dies, it's like tripping a circuit breaker. So, the car sounds like it started, you release the key, it dies instantly. Almost like somebody threw a switch. But, as I said, I could be completely misunderstanding what he is trying to say. His description is a bit vague.
Oh, OK. Thanks for 'splaining. Makes perfect sense now. (if he has a tach)
No I dont have a tach... anyway I think the timing is probably off. I am going to try to adjust it tonight or tomorrow. I heard some one say you could just change all the plug wire positions on the dist and it would possibly fix the problem without having to turn the dist? I dunno. Has anyone heard of this? How does it work. Thanks.
Turn the engine over until #1 cylinder is at the top of the compression stroke.You can do this by removing the spark plug and turn the engine over with a big socket on the bolt holding the vibration dampner.you will feel the air being pushed out of the plug hole.line up the timing marks on the vibration dampner to 0 on the dial.This is where you start from.Look at the rotor on the distributor.It should be pointing at #1 cylinder.That is where your wire for #1 should be on the cap.Install the cap and wire it from there,counterclockwise following the firing order.turn the distributor clockwise to advance the timing to the initial timing degree.
Well, I had the wrong book I guess. I followed the firing order that was on the intake manifold instead, and now it turns over way better, and I had to started for like half a second, but it just wont stay. I wander if the timing is still a little off? I dunno, Ill try to adjust it more. That solved the backfiring problem also.
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It might also be that the resistor wire has an open, as stated here, a jumper from the battery to the positive side of the coil would do a lot for diagnosing the problem.
Also with the ignition switch on, a test light can be used on the + side of the coil. The light should burn somewhat dimmer than a connection directly to the battery.
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New classic mustang Starting Question - 
If you are saying that, you turn the key to the start position, it cranks and sounds like it started, you release the key, and the motor dies instantly, then more than likely, your tach went south on you. If you go behind the instrument cluster and look at the back of the tach, you will see two wires coming out of the back of the tach that have bullet connectors a few inches back from the tach. Unplug those two wires and plug the two wires that go back to the harness together. Not the two short wires that are still hanging out of the back of the tach, but the other two that those wires were plugged into. Your problem, if it is doing what I asked you if it was doing, has something to do with the resistor wire that goes from the 'on' position of the ignition switch through the tach and eventually out to the coil. It could be the wire itself, or possibly the ignition switch, but that problem is almost always a dead tach. Hope that helps.
It sounds like what he is calling backfiring is something that started to happen only after several failed attempts to start the car. If that is in fact what happened, it isn't a distributor or timing problem.It's probably the result of all that gas he said was getting to the carb starting to puddle up in his intake. But, you never know.
