Condensor cause no spark?

[surfdogskier]

Would a condensor cause cause the plugs not to spark? I tested my coil and it is good. I did a bypass thing to check the coil and used a spark plug gap tester. I am getting spark from it. My points gap is good. Braid wire is good. It just seems that once it gets to the distributor, it disappears. Only thing else I can think of is the condensor.

Turns over great just wont start.

Any help would be appreciated.

1972 914 1.7L

[Dave at Pelican Parts]

A bad condensor could cause that. So could bad points. So could a variety of things.

I don't know exactly what you mean by "did a bypass thing", so I don't know what that really tells you.

A few things to check:
- Do you have +12V on the coil (+) terminal when the key is on?
- Do the points short to ground and then disconnect as they open and close?
- Are there any frayed or damaged wires in the points circuit?
- Have you tried with the tach signal wire disconnected from the coil (-) terminal?

You can check your coil with the following steps.
Hook an extra spark plug wire to the center terminal of the coil. Put an extra spark plug into the other end. Tape the plug so that the outer part is contacting a good ground.
Unplug the other wires from the coil. Now hook up a jumper wire to ground. Hook up a second jumper wire from a "hot" power source (the battery (+) terminal may be a convenient one) to the coil (+) terminal.
Touch the other grounded jumper to the coil (-) terminal and then take it away again. You should see a spark at the spark plug. No spark means a bad coil, or one of the jumpers is bad, or the plug wire or plug are bad.

--DD

[surfdogskier]

Originally Posted by Dave at Pelican Parts

A bad condensor could cause that. So could bad points. So could a variety of things.

I don't know exactly what you mean by "did a bypass thing", so I don't know what that really tells you.

A few things to check:
- Do you have +12V on the coil (+) terminal when the key is on?
- Do the points short to ground and then disconnect as they open and close?
- Are there any frayed or damaged wires in the points circuit?
- Have you tried with the tach signal wire disconnected from the coil (-) terminal?

You can check your coil with the following steps.
Hook an extra spark plug wire to the center terminal of the coil. Put an extra spark plug into the other end. Tape the plug so that the outer part is contacting a good ground.
Unplug the other wires from the coil. Now hook up a jumper wire to ground. Hook up a second jumper wire from a "hot" power source (the battery (+) terminal may be a convenient one) to the coil (+) terminal.
Touch the other grounded jumper to the coil (-) terminal and then take it away again. You should see a spark at the spark plug. No spark means a bad coil, or one of the jumpers is bad, or the plug wire or plug are bad.

--DD

Hey Dave,

What is meant by the bypass thing is the way you described checking the coil. I did get spark that way.

To answer your other questions

A few things to check:
- Do you have +12V on the coil (+) terminal when the key is on? YES
- Do the points short to ground and then disconnect as they open and close?Not for sure on this. I do have them gapped correctly. They are new.
- Are there any frayed or damaged wires in the points circuit? No. I put in new points
- Have you tried with the tach signal wire disconnected from the coil (-) terminal?No. I have not tried that. I will do that and see if that helps.

Except for those 2 things, the only thing I could think would cause some type of issue was the condensor.

[Dave at Pelican Parts]

Unplug the points inside the distributor. Make sure that the connector gets shorted to ground and disconnects as the points open and close. It's not unheard of for new parts to be bad out of the box, or to die right after they're installed...

--DD

[surfdogskier]

Originally Posted by Dave at Pelican Parts

Unplug the points inside the distributor. Make sure that the connector gets shorted to ground and disconnects as the points open and close. It's not unheard of for new parts to be bad out of the box, or to die right after they're installed...

--DD

I will do this weekend.

Curious, why do you suggest disconnecting the tach wire on the coil, the purple/black wire? One thing that is crazy about my tach is when I turn on the key, the tach buries all the way to the right past the farthest RPM measure. Is this normal?

[Dave at Pelican Parts]

The tach gets its signal from the points. If the tach shorts to ground internally, the points will effectively never open; the wire going to them will always have a path to ground. (Either in the distributor, or in the tach.)

I have seen "anti-theft" switches that shorted the tach wire to ground, preventing the motor from running. I thought it was a clever strategy, but it does add extra potential failure points to the circuit.

Having the tach needle peg to the right is not normal, and makes me very very suspicious that the tach is causing your problem.

--DD

[surfdogskier]

Well I disconnected my tach and still no spark. I am going to pull my distributor and plug wires and connect it directly to a battery using a switch for the key. I saw a video on this in Youtube. If I turn the bottom of the distributor where it goes into the cam, it should be getting spark when the points connect (or don't connect, can't remember). I cam going to see if it is my condensor or if my points are bad even though they are new.

Even with my tach disconnected, it still buries all the way to the right. Any ideas why?

[Dave at Pelican Parts]

It is borked or hooked up wrong.

Double check the connections on the back; make sure you don't have power or ground plugged into the signal terminal.

If it's plugged in correctly and still reads like that, the tach itself is messed up and needs to be repaired. I know that North Hollywood Speedometer and Palo Alto Speedometer are the gold standard for gauge repairs; they will likely put the guts from a more modern tach into yours to do the fix. (Make sure they calibrate it for four cylinders; PA Speedo did a tach for me that wound up reading far too low because they accidentally made it a six-cylinder tach!)

--DD