Hi Guys, my issue has returned. I have a new ignition switch, new battery and a rebuilt starter.

Sometimes after driving when the engine is at normal operating temp. and I shut down the car, the engine do not crank. I just hear a click at the starter.
I have used a remote ignition switch to jump the battery directly to the starter terminal and engine cranks up fine.

Also, this issue seems to be more severe when i shut down the car after running for a while. When the engine cools down or sitting overnight it might crank up after 2-3 tries.

Any thoughts? I was thinking of getting a new starter to see if it is a bad solenoid first?

I would have the starter tested for sure. It's easy to get off on these cars and free testing at chain stores. Also clean and tightening the wires really good could help. Might be a bad ground or the spade connector on the solenoid needs cleaning and crimping down a little tighter. I did that backwards . Check the wiring 1st then pull the starter.

Sounds like a shitty remanufactured starter to me. I've learned to have them tested before I buy. Starters, alternators etcetera.

You should check the voltage on the battery when it won't crank, possibly low of water/acid or a failing battery. Do a 24 hour 2 amp charge and make sure the fluid is topped off. Leave the covers off while charging and put an old rag or towel around the acid/water holes.

Should show around 14 volts while running, 13 at least. Cold weather is a battery killer.

On 1/31/2025 at 5:07 PM, MH77280Z said:

I have used a remote ignition switch to jump the battery directly to the starter terminal and engine cranks up fine.

This is odd though.  Kind of suggests low current to the starter solenoid.  There's no relay, power passes through the ignition switch directly to the solenoid terminal.   Edit - It's an automatic!!!  The path from the battery through the fusible link to the ignition switch and on to the starter solenoid would be worth checking.

But it could be that the starter solenoid is too weak for the ignition switch current but the jumper gives it just enough to get over the top.  I'm not sure that the parts store test will catch that.  Might be worthwhile to just tell them it's bad and get a replacement if it's one of the "lifetime warranty" starters.

 

Edited February 5Feb 5 by Zed Head

Let me try replacing it also. Is it hard to get the starter in/out of a 280z? it is pretty accessible from the engine compartment.

5 hours ago, MH77280Z said:

Let me try replacing it also. Is it hard to get the starter in/out of a 280z? it is pretty accessible from the engine compartment.

It is a little awkward. I usually need to let my back rest after I do it.

What cold battery voltage do i need to crank the 280z?

My battery voltage was showing 12.9v and was not cranking. I used the remote starter again to get it running at that voltage. After running for about 5 mins the battery was showing 13.57 volts. Shut the engine down and tried cranking normally again - no luck. Battery voltage dropped to 12.5v at that point.

Planning to charge it overnight to see if it goes any higher.

 

12.9 should be plenty!

Even 12.5 should spin it.

6 hours ago, MH77280Z said:

What cold battery voltage do i need to crank the 280z?

My battery voltage was showing 12.9v and was not cranking. I used the remote starter again to get it running at that voltage. After running for about 5 mins the battery was showing 13.57 volts. Shut the engine down and tried cranking normally again - no luck. Battery voltage dropped to 12.5v at that point.

Planning to charge it overnight to see if it goes any higher.

 

Those are good. Battery and alternator seem fine. I do believe you could have starter issues.

 

Overnight charging had the battery at 13.25v and it did not crank. Getting a new starter from Orielly's and asking the rebuild guy to take a look at the current one again. Current one was re manufactured locally. Will report back.

Edited February 3Feb 3 by MH77280Z

I don't think it's the alternator. Your battery would be much lower than 12.5 if the alternator was dead.

It's probably either a bad starter, a bad wire or a dirty connection...

2 hours ago, Patcon said:

I don't think it's the alternator. Your battery would be much lower than 12.5 if the alternator was dead.

It's probably either a bad starter, a bad wire or a dirty connection...

What are the common dirty wire culprits I can look at while I wait for the starter to arrive tomorrow? I checked all 4 fusible links for continuity and they are fine.

Edited February 3Feb 3 by MH77280Z

Here's the basic grounds that should be cleaned and shined up. It doesn't take too long, an hour at the most, and really helped my EFI 280.

https://atlanticz.ca/zclub/techtips/electricalconnections/index.html