Cold start issue

[OniZ]

I would have posted this in electrical because it seems like that is the problem but i could be wrong and it is something else. Anyway i have a 71 carbed Z and the problem is when i go to start it early in the morning it doesn't start. No click, whine, trying to start nothing. Now once it gets warmer then it will start. Is the weather affecting the electrical or the mechanical? I want to try a blanket over the motor to see if that helps it start. Any ideas other than this the car runs fine and starts fine.

[Inf]

No click? Next time you have the problem, disconnect the leads on the starter solenoid and check to see if your key turn to "start" in the ignition is giving any juice there (with a voltmeter).

If the solenoid is getting power when you turn your key, but not clicking on and giving juice to the starter, then there's your likely problem... Replace the solenoid.

I would definitely not do anything involving a blanket... First of all, a blanket keeps your body warm because YOU are producing thermal energy, and the blanket slows the heat flow into the environment. An engine that is not running will not benefit from a blanket because it is not producing any thermal energy.... Secondly, I envision someone forgetting/not knowing it's there, and you've got a whole other kind of disaster on your hands.

My 2 cents, but that's what comes to mind every time I hear a "battery is fine, but there's no click or anything when I turn the key" story.

[MK1888]

Does the battery read over 12V in the morning? I think 12.6V is fully charged. If the cold is affecting the battery you could keep it warm by taking it inside the house overnight and see if you have a problem the next morning.

Just so you know, the "click" is the solenoid pushing the gear out to engage the flywheel. No click means either the solenoid is bad or there isn't enough power getting to it. But generally, a weak battery will still push out the solenoid and just not turn the starter.

Temperature can definitely affect electrical parts, especially old parts.

[Nissanman]

Cold environments are detrimental to batteries, if they are borderline.

Cold also causes metal to contract and that also means wiring.

If there is a faulty wire or connection somewhere, cold can cause that electrical function to be kaput until it expands again.

But, as already mentioned, check the battery voltage prior to cranking the engine.

If it is at least 12V then that is reasonable.

The next port of call is the starter solenoid etc.

Electrickery is really good fun, really:rolleyes: