Starter Help - Melted Wires

[techguy]

I think my car hates fun runs! Had a great day the PCA group toured Dream Car Garage (Speed Channel), at the end got some gas, then went to eat. I came out to start the car and it turned over for about 2 seconds then slowly died. The battery is new and was @12.75V, new Alt, and new VR. I figured the starter died or some of the wiring was dirty. This is what I found:

Wires E and F look melted and touching a blob of connection B.

What I would really like to know please:

Wires "C" and red wire (upper) connection "D" goto the alt and battery +'ve terminal.

1) What does connection "B" goto? It was found touching (fused) to the side of the starter.

2) Are wires "E" and "F" (upper pic) suposed to be stuck together or are they just melted? They cam from connection "A"

3) Is connection "D" (lower pic) used for anything?

The alt seems to be missing one tooth and was just making a click sound when I removed it from the car. Thinking about having it rebuilt.

[RoninLB]

did the starter jam at the flywheel and you kept the ignition sw in the "start" position when it was jammed ?

[techguy]

The starter was turning over for several seconds then just slowed and quit. It made the traditional tick tick noise afterward. I got the guy from the tow truck company to give me a push start and it fired right up.

[Randy Webb]

The main wire from battery + and the wire to the alt. meet at the big lug.

The tab wire will be for control.

Sorry to hear about the problem.

[techguy]

Reading archives for hours, is this correct?

Terminal "C" goes to Alt and +ve Batt lead

Push on clip for wires "E" and "F" belong together on connector "A"

Terminal "B" goes to ground..WHERE??? It was a mess!!

Second push on clip (lower pic) D is unused.

Am I close?

[911pcars]

Techguy,
C goes to the battery pos. terminal through the red battery cable you have labeled "D" in the upper pic.

In the lower pic of the starter, B provides source voltage to the starter motor (from C) when the solenoid is energized. B usually has an insulated metal connector leading into the motor. Not sure about the frayed braided wire I see.

However, if B is grounded when the solenoid energizes, there will be a direct short to ground, thus the melted wire hanging off of the B terminal. That was probably the weakest link in the source circuit and it melted.

The control wires, E and F, may have melted because of the heat generated by the short circuit.

My best guess, but compare color code with the wiring diagram to be sure.
Sherwood

[techguy]

Thanks for the info guys, I am wondering if "B" really is a ground. I just found this pic on the net and it looks like "B" goes into the body of the starter. Can anyone confirm.

[911pcars]

If you don't see any other electrical connection leading into the motor housing from the solenoid, then B is the source wire from the solenoid. It fried due to a short circuit.

Sherwood

[techguy]

Thanks Sherwood,

I was unable to find any other wires from the solenoid to the motor. So connection C is power from Batt to starter and continues to alt. B is the source wire to the motor and the motor gets its ground at the transmission. "A" then connects to the ignition.

It sure looks like a short at the the wire off B (it was all white) where it was touching the body of the motor with the yellow wires all touching the same point in a melted blob.

I think I may cut the last 1" off the yellow wires, solder on a new connector and have the alt rebuilt or buy a new one from PP.

[RoninLB]

Originally posted by techguy

It sure looks like a short at the the wire off B

cut the last 1" off the yellow wires, solder on a new connector

and have the alt rebuilt or buy a new one from PP.

good thread.. finally a good starter thread.

The broken tooth happened for a reason.. maybe flywheel fun's a coming. How about you carefully inspect all flywheel teeth ?

So IF I assume there was a binding of the motor, at full battery current flow, there's a lot of heat happening somewhere. And if I assume the binding didn't allow full plunger throw.. which may have created a voltage drop of the plunger disc and battery/motor connections.
so I figure the sol disc is toasted and the heat melted the small wire insulation.. which means the small dia wires only need new insulation.. I'd still confirm this with a voltage drop test later when repair is completed.

Really thou.. if the motor field connector melted then there was full plunger, I think.. The motor field coils would have caused the high heat... and the big, pia it install, positive battery cable core could have been damaged..

I think voltage drop tests latter will be called for imo...

where's education.. I mean Warren ?

[pwd72s]

FWIW, I have a rebuilt starter in my garage, awaiting shipment to Evren. The "B" has a ground (?) wire, as in the posted pic...

[techguy]

What does the "B" wire look like? Mine was fried.

[RoninLB]

Originally posted by techguy
What does the "B" wire look like? Mine was fried.

I don't have a pic of the motor feed from the sol.. but you might consider up-grading the stock starter to a high torque unit.

I have a Tilton, but Wayne sells a better unit according to some pelicanheads.

[911pcars]

Your first post:

"Thinking about having it rebuilt"

I'd do that. Find a rebuilding shop. They can check it out, replace the needed parts and bench test to ensure it's okay.

Sherwood

[Early_S_Man]

As Sherwood already said ...

Terminal 'B' off the solenoid is the switched 'hot' lead going to the brush assembly inside the starter motor! Normally there is a heavy rubber grommet protecting it from grounding against the starter frame.

[techguy]

Perfect!! Thanks guys, it is so much easier rewiring or reconnecting everything when one has an idea of what is being connected. Melted plastic blobs are not the nicest to work with. Getting local quotes of $150cdn to rebuild with new brushes, solenoid, gear, etc.

[Grady Clay]

The best bet is to exchange your starter for a factory Bosch rebuilt 1.5 HP starter. You get all new parts, only the housing is used.

Yes, you need to carefully inspect and repair the wiring all the way back through the system.

Yes, Terminal B is the switched power to the motor.

From my lame old memory, D is the connection from the ignition switch (yellow wire, push-on connector is 90 degrees to the wire.)

Is A a ground connection or is it a duplicate connection to the ignition switch?

Yes, you should inspect every tooth on the ring gear. You can inspect/measure flywheel/ring gear runout through the starter opening. Make sure the flywheel isn’t loose on the crankshaft.

Best,
Grady

[pwd72s]

Originally posted by techguy
What does the "B" wire look like? Mine was fried.

Sorry about the delay, just got on. No digital camera here, but I'd describe it as a mini version of the braided battery ground strap, with a woven insulating cover that is brown in color...kind of reminds me of the insulation they used on lamp wires before plastic insulation took over..

[techguy]

Hey guys, can I use connection "D" for a remote start to test the starter or for running compression tests at the back of the car? or Is there an easier setup?

Thanks again for all the great support.

BTW the guy at the rebuild shop specializes in Porsche starters and Alts, he is also teamed up with a guy who runs a Porsche engine rebuilding business next door. I figure since my starter is a Bosch factory rebuild I am going with the rebuild again....if it fails I have a warranty, worse case I buy a new one from PP. I like the 2 day turn around with no customs or $ conversion.

[techguy]

I guess I could tie into the thermo time switch in the engine compartment for a remote starter setup, the wiring diagram looks like it ties into the ignition side of the starter right??