A quick Question, starter issues.

Ericv · 04-25-2009, 01:32 PM

I"ve probably read 12 pages of prevoius posts to try to solve my starter problem. I have a 70T with a 69E engine that I've been working on for a year. I'm to the point where I would like to fire it up. I've jumped terminal 30 to 50 and the starter engages fine. There's a steady supply of 12.4 volts going to terminal 30. The PO wired a starter relay in because he did not want to replace the ignition switch. The relay appears to be functioning correctly. There's 12.2volts going to the relay and when the starter button is pressed, the relay coil is energized and sends 12 volts out another wire. So, my question is this. Is the yellow wire that connects to terminal 50 tied in with the relay? When I press the start button, I get no voltage at the yellow wire which from what I read should engage the solenoid. Please help as I am not good with electrical connections. Thanks, Eric

Ericv · 04-25-2009, 02:07 PM

I neglected to mention that the transmission ground strap is new. If I turn the ignition switch, I hear one click. If I press the engine start button, there's no power to the yellow wire. Thanks again.

911pcars · 04-26-2009, 12:38 AM

Separate switch to crank the engine?

When the ign. is in the crank position, source voltage from terminal 30 connects to 50 (yellow wire). This yellow wire energizes the starter solenoid. Sounds like the "crank" or "start" position in the ignition switch is NG. It happens.

There's normally no relay for the start circuit on these MY cars.

Sounds like the PO may have disconnected the yellow wire at some location because of the malfunctioning ign. switch, then installed another 12 volt source wire to energize the separate starter switch and relay circuit to energize the starter solenoid.

That sound about right?

Sherwood

Ericv · 04-28-2009, 04:18 PM

Yes, that sounds right. Instead of replacing the ignition switch he put in a starter relay because it was cheaper. I finally diagnosed that the relay was bad and replaced it. So, I think I've gotton all of the electrical bugs worked out. When the start button is pushed, I get 12.4 volts to the yellow wire. Terminal 30 or the battery wire is getting above twelve volts as well. When I push the start button, there still is no activity from the starter. I can manually jump terminals 30 and 50 with a screw driver and the starter turns the engine slowly. Is it now safe to assume that the starter is bad and needs replacing? Thanks for your help.

911pcars · 04-28-2009, 04:30 PM

I use a remote switch and relay as well to save the NLA ignition switch. Here's my diagram.

http://members.rennlist.org/911pcars/RemoteStarter.htm

Might be similar to yours. Not sure what terminals the PO used. Since the relay clicks, you should be getting source voltage at the wire (30 or 87) that goes to terminal 50 of the starter solenoid. If the solenoid doesn't click, the solenoid is bad or isn't grounding correctly. If the starter clicks but the starter doesn't rotate, it could be the connection between the solenoid and motor (large copper disc) and/or the starter is malfunctioning.

Sherwood

Ericv · 04-28-2009, 04:44 PM

Thanks for the advice, I get a click from the relay but nothing from the starter. So it sounds like the solenoid is bad. I'm Pretty sure it grounding corectly. When I hook up the multimeter, I ground it on the transmission ground strap and I'm getting a good signal. I guess it's time to do some shopping for a starter. Again, thanks for your help.

Ericv · 04-28-2009, 04:55 PM

Are there any good suggestion for a starter or will the rebuilt supplied by the host do the trick? Thanks

EarlyPorsche · 04-28-2009, 05:03 PM

I bought a rebuilt Bosch from a member here and it works really well. You could buy one here or get your current one rebuilt locally.

Ron Broman · Ron Broman's Garage

Check you fuse bus in the engine compartment. My starter gave me a fit until I disconnected the batteries and used a wire brush on the fuse bus and the ends of the fuses.
Hey, it happens!!

Ericv · 05-05-2009, 04:26 PM

O kay, So I purchased and installed a rebuilt starter. The problem is this. When I disconnect the yellow wire from terminal 50 and press the start button, I get 12+ volts from the relay. When I plug the wire into terminal 50 and press the start button, no voltage registers on my multimeter. What could be going on with this issue? It's deceiving because I thought I was getting 12 volts to the solenoid. Also, if it helps, I get no voltage from the positive side of the coil as well. Any help is appreciated. Thanks

911pcars · 05-05-2009, 05:46 PM

Quote:

Originally Posted by Ericv

O kay, So I purchased and installed a rebuilt starter. The problem is this. When I disconnect the yellow wire from terminal 50 and press the start button, I get 12+ volts from the relay. When I plug the wire into terminal 50 and press the start button, no voltage registers on my multimeter. What could be going on with this issue? It's deceiving because I thought I was getting 12 volts to the solenoid. Also, if it helps, I get no voltage from the positive side of the coil as well. Any help is appreciated. Thanks

Just to review. The PO installed a separate relay to energize the starter solenoid. The ignition switch is merely used to provide source voltage to the ignition system.

When you press the aftermarket starter button, the relay should provide a voltage path from the battery to the starter solenoid via the relay (the power side of the relay). The yellow, #50 wire to the relay now only acts to energize the relay (the control side of the relay), not to energize starter solenoid.

If possible, identify and record the corresponding relay numbers and their current path.

Sherwood

Ericv · 05-06-2009, 03:57 PM

There's a big red wire (I assume the 12volt battery wire) that goes to 87 and the aftermarket start button,

The yellow wire goes to 30 on the relay.

86 on the relay goes to the after market start button.

85 on the relay is a ground.

Today I cleaned all of the ground connections. Replaced the positive battery post with a gold plated post. Replaced all fuses and took a wire brush to the fuse box. I still get a click from the relay when the aftermarket start button is pushed. The connection at the relay for terminal 50 puts out 12.5 volts but when it's measured at the starter, it's 0.1 volts. Hope this helps. Thanks.

911pcars · 05-07-2009, 09:04 AM

Quote:

Originally Posted by Ericv

There's a big red wire (I assume the 12volt battery wire) that goes to 87 and the aftermarket start button,

The yellow wire goes to 30 on the relay.

86 on the relay goes to the after market start button.

85 on the relay is a ground.

Today I cleaned all of the ground connections. Replaced the positive battery post with a gold plated post. Replaced all fuses and took a wire brush to the fuse box. I still get a click from the relay when the aftermarket start button is pushed. The connection at the relay for terminal 50 puts out 12.5 volts but when it's measured at the starter, it's 0.1 volts. Hope this helps. Thanks.

Your description doesn't indicate what side of the relay voltage is being measured. Source voltage should be 12v on both the control and power side of the relay.
Output connection on the control side should go to ground. Output connection on the power side of the relay should go to the starter solenoid and indicate 12v when energizing the relay.

Temporarily remove the wire from the starter solenoid, then connect the meter test lead to it. Press the start button and measure voltage. It should be 12volts. If voltage is 0, the relay isn't working correctly.

If 12V and the solenoid doesn't "click", then the solenoid is malfunctioning. If the solenoid "clicks" but the motor doesn't rotate, the motor has a malfunction or the electrical connection between solenoid and motor is faulty.

Sherwood

Ericv · 05-09-2009, 03:17 PM

I would like to add a follow up to this thread. The wiring to the relay was incorrect. I downloaded a diagram from Pelican and rewired the 12 volt power source to 30 on the relay. 86 on the relay was ground and 85 went to the aftermarket start button. The yellow wire went to 87 on the relay. I eventually found that I was not getting continuity from the yellow wire. I made a temporary yellow wire for a test and that did the trick. Apparentley, wire doesn't last forever. I rerouted a new yellow wire in the tunnel and now my starter is working perfectly. Now I have to figure out why the coil is not getting any power. Here's to another thirteen pages and the search function. Thanks for all of the help.

911pcars · 05-09-2009, 10:23 PM

Quote:

Originally Posted by Ericv

I would like to add a follow up to this thread. The wiring to the relay was incorrect. I downloaded a diagram from Pelican and rewired the 12 volt power source to 30 on the relay. 86 on the relay was ground and 85 went to the aftermarket start button. The yellow wire went to 87 on the relay. I eventually found that I was not getting continuity from the yellow wire. I made a temporary yellow wire for a test and that did the trick. Apparentley, wire doesn't last forever. I rerouted a new yellow wire in the tunnel and now my starter is working perfectly. Now I have to figure out why the coil is not getting any power. Here's to another thirteen pages and the search function. Thanks for all of the help.

Incorrect connections to the relay, faulty wire or both? At any rate, I'm glad it worked out in your favor. The diagram I referenced in post #5 shows a schematic drawing of an add-on relay and the proper connections to and from it.

Sherwood