CutterComp

On the face of it, this seemed simple to me, I rebuilt the 968 starter and ordered a new aftermarket (made in Brazil) starter solenoid because the original I thought was dead. The new solenoid arrived and I decided to bench test it before mounting it to the starter. I did this by grounding the solenoid body and providing +12v to the lug that is normally directly connected to the battery positive terminal in the car and +12v to the small signal lug. I get zero response from the new solenoid when doing this. Same with the old solenoid.

That said, I have a few older Bosch PMGR (permanent magnet gear reduction) starters laying around from other German cars so I pulled a few solenoids off them to bench test. They all work correctly when testing via the same method.

This leaves me to believe the new solenoid I received (and my 968 original) is DOA but the vendor is telling me I'm testing it incorrectly by grounding the body of the solenoid. As yet, I haven't received a direct response to how it should be grounded otherwise. Still, if I'm doing this wrong, I'd like to know! I don't claim to be an electrical expert. Please confirm I'm correct or tell me why I'm wrong.

Thanks.

LM964

There are a few online (Google, YouTube) resources that provide a test procedure. Hopefully one or two will apply in your case. Does seem odd though that any new replacement would require a test proc different to the standard/generic. Post up what you find out..

Paul Waterloo

I would think it is just grounded on the body. Test to see if you have continuity from the power lead to any part of the starter, if you do, you know the circuit is good, if you have an open circuit, no power is going to flow. Post up some pictures of the solenoid.

This won't necessarily help you, but my solenoid was bad, I replaced the whole starter, can't remember the details except it wouldn't start.

https://rennlist.com/forums/968-foru...eperately.html

Paul Waterloo

Went through my pictures, and in my case, the starter solenoid coil still had continuity but it would not pick up the starter. It had 1.2-1.3 ohms. Check yours out and report back. If you just bolt it up to your starter, you could test everything together with jumper cables from a battery.

CutterComp

Update: I was able to get the new solenoid to work by placing the +12v cable to the longest lug, the -12v cable to the shorter lug, and then a small jumper wire to the solenoid signal post with +12v. Worked great that way; saw it suggested somewhere in the annals of the internet by someone else working on an older Porsche solenoid. FWIW, my old solenoid worked that way too but was very sluggish so I was glad I bought a new one.

What I don't understand is why these Porsche solenoids don't work the same as do my other Bosch PMGR solenoids.

Regardless, I put the starter in the car and it cranks faster than it has in many years, so I'm happy.