84 svo won't crank

[Desert Patina]

Can you check two things...

Disconnect the small red-blue wire from the top terminal on the starter solenoid, and then turn the key to start. Check the voltage from the terminal at the end of the wire to any convenient ground. Should be more than 11v.

While the key is in start, use a jumper wire and press one end on the positive terminal on the battery and the other on the terminal on the solenoid the red/blue wire would normally go. It should actually try to crank over at that point.

The first test validates the ignition circuit from the battery, through the ignition switch and clutch and neutral switches.

The second test validates the last part of the switch / solenoid circuit (from solenoid to the negative terminal of the battery), including the actual start/power circuit from the battery, through the relay, to the starter motor and back through the ground cable to the negative terminal on the battery.

It would actually be better to do the second test as isolating the circuits by removing the power cables from the solenoid, and simply test for resistance (should be 0) across the large terminals while the wire from the battery is still charging the starter solenoid.

[mrzw70]

I disconnected the small wire at the terminal, mine has two wires connected at that terminal that are red with white stripes though. I checked voltage across it and ground and got more than 10 volts. It was hard to tell with my meter, spiking well past 10 though. I then tried crossing from the positive post to the terminal on the solenoid that the red and white wire connects to and the solenoid pops like it does with the key but no start. I then touched it from the positive terminal to the starter post and the engine fired right up.

[Desert Patina]

that must have been some jumper wire....

Someone can correct me if I'm wrong, or reading it incorrectly, but you can be pretty sure the solenoid is your issue.

[Under Pressure]

Just because you are reading voltage doesn't mean it can draw the amperage to engage the starter. It sounds like you have a bad ground or a weak battery. I'd bet the heavy ground wire is bad.

[JTurbo]

Is the solenoid securely mounted to the chassis? If it's loose you don't get a good ground and it won't crank.

Note that the factory used glorified sheet metal screws that tend to not hold the solenoid all that tight.

[mrzw70]

A correction to my previous post; I jumped a wire from the positive post on the battery to the post on the solenoid that runs to the starter and yes it was an old amp wire. All else still applies. I tried another battery the other day with the same result. This is a second solenoid which is brand new and it is screwed very tight to the strut tower, albeit with the factory screws. Should i try scratching the paint from the tower to try to get a better ground? Both battery cables are brand new and in excellent shape.

[Desert Patina]

That is what I figured you did. It came through clear.

Also, I'm not worried about the battery if it actually started the car. The amperage that it takes to click a solenoid is far less than to turn the starter.

Did you do the test where you engaged the solenoid itself, with no starter wires connected to it, just to measure the resistance when it was engaged?

[mrzw70]

I will try that next. I measured across when I tried to start it from the hot post to the starter side of the solenoid and it showed no voltage though. I did not check for resistance across the solenoid.

[mrzw70]

Finally got it to start with the key. Stupid mistake on my part, I had the under hood light hooked to the solenoid for some reason. I'm not sure why, I just started chasing wires and realized it shouldn't be there. Removed it, and it fired right up. Thanks for all the trouble shooting advice.

[Desert Patina]

Always a good ending when its a simple fix.