The car is a 1990 760 turbo.

The starter runs continuosly, even with the key to the "off" position -- even with the key OUT of the ignition, far as that goes. I had to disconnect the battery to get the starter motor to stop spinning. Doing this didn't reset anything -- the starter motor still spins when I reconnect the battery cable.

Prior to this, occasionally the starter drive would kick out of the flywheel prematurely on an occasional basis -- say about once out of every 20 times I started the car. I dunno if it's related to this issue, but I just thought I'd mention it.

When this problem occurred, the starter cranked the motor over as it always does, then the drive kicked out (before the motor caught), and the starter kept running.

Coincidently, an old motorcycle I own developed a starter problem also today (seems like I have starter karma right now), and looking through it's manual, I found a troubleshooting comment that listed the starter relay as being a possible culprit if the starter continues to run. So, I'm wondering if this sounds plausible?

Is there a way to test the circuit such that I can isolate the problem, be it the starter solenoid or the relay?

Thanks in advance for any help you can provide.

Best,
Michael

Thanks for the responses.

About the key cylinder, I know what you mean. My '88 760's had to be replaced. This car's was replaced sometime before I bought it, but it seems solid enough now.

About the solenoid -- I was wondering if it might be stuck in the "on" position as well. Was hoping it might be something more simple, like the relay, but before I have to remove the starter -- which I did before with my '88 and it wasn't all thta hare -- I was hoping to find a way to troubleshoot the problem before I have to go to all the trouble of removing the starter.

So, anybody got any troubleshooting advice?

Best,

Michael

Replace your starter

Sounds like the starter solenoid stuck ON.
Don't whack at the starter to free it since you can
break the field magnets loose.

I'd get another starter at the junk yard, or repair yours.
The starter comes apart easily and is not too hard to reassemble
by using the right size (OD) socket to seat the four brushes for reassembly.

Pulling the starter is an easy job EXCEPT that the top starter bolt has very little clearance to the firewall. I used a 3' extension and had to struggle
to find the right combination of a swivel and a thin wall 3/8 impact socket,
with the extension above and close to the driveshaft. It was easy to get the
socket jammed up into the firewall.
Maybe others have a better idea for getting that pesky upper starter bolt
out. Maybe an extra shallow swivel socket would be a good idea?
I forget the size, maybe 15mm.

Bill

According to an indie Volvo tech I have used, the key cylinder on the 760's are prone to problems. Mine is loose as a goose on my 89 760, but upon checking it, he said it was still OK.
Things was, he was really expecting it to be bad.

Might be a place to consider looking.
--
' Of all bad men religious bad men are the worst. '' (C S Lewis ; on Evil Men) 89 764 (170K), '94 940T (265K), 92 245 (150K)