Starter Troubleshooting

[superglide]

Can anyone help with the troubleshooting steps for the starter on my '82 911sc? The car has been laid up for 6 months while I searched for a new front oil cooler line, and sat in my backyard, covered.

After I installed the new oil line and buttoned it all up, I replaced the battery with a new charged correct one, went to start the car and nothing but a weak click happened. When I tried the lights there was plenty of juice, but when I turned the key to start with the lights on; they went out until I released the key. The starter is at least 7 years old that I know of, and has never given a bit of trouble previously. As it was getting dark, I didn't visually inspect the starter for wild animal damage or anything, but I'd like to know the steps necessary to troubleshoot the starter system. Any help or advice will be appreciated.

[Gunter]

To determine that it is not the electrical portion of your ignition lock, or the yellow wire from the lock to the starter solenoid, lift up the car with jack stands under the torsion bar covers, gears in neutral.
Ignition ON, now crawl under there with a screwdriver and bridge the connection from the starter to the solenoid with the srewdriver.
Expect a spark and noise when the solenoid kicks in and the engine starts. Make sure the car is well secured on stands. Safety first.
Or, put the new battery close to the starter, rig up a heavy +wire and a heavy ground wire to the starter. Now supply a smaller 12V +wire to the solenoid. It should click in and rotate the starter.
If you are not comfortable doing this, let someone else do it.
Connections to the starter: Big red (Alternator) and black (Battery)
Connections to the solenoid: Yellow wire from ignition lock and on the same connection, another yellow wire to the Cold Start Valve.
A lot of times when the starter doesn't get enough juice it's a bad ground. Check all ground straps, especially the one from the transmission to the body and the short neg cable from the battery to the body left side fender. Remove the straps, clean the connections, use dielectric grease and re-install.
Let us know.

[superglide]

Dr. G,
A thousand thanks for the info & advice! I'll give this a whirl, after work today, and let you know the outcome, if any. one more question; I want to be sure that it isn't a frozen motor (god forbid), so from the rear of the car facing forward, which direction is the engine rotation? Clockwise or counter clockwise? I've heard that some motors can be damaged by turning them the wrong way...
Best Wishes,
Andy

[Gunter]

Clockwise.
Ignition off.
Put a large socket on the big fan-nut, then squeeze the belt together while turning the fan cw.
It should turn (Reluctantly) even with the plugs in.
6 months storage does not freeze up the engine.

[jmohn]

Gunter's procedure will determine if the solenoid and starter are good, but not the ignition switch or the yellow wire from the switch to the solenoid (because you're actaully by passing that entire portion of the switch). If the starter doesn't turn using Gunter's procedure the starter-motor/solenoid is bad. If the starter does turn the problem is in the switch or wiring. I recently had to replaced the yellow wire from the switch to the solenoid on mine ('78 SC, I actually ran another yellow wire). Assuming all the grounds and connections are clean and sound, if the starter turns using Gunter's procedure, I think you need to look at the electrical portion of the switch and/or the continuity of the yellow wire from the switch to the solenoid. On mine the switch was OK, and the yellow wire showed continuity, but wouldn't allow enough current to "trigger" the solenoid.

(BTW the yellow wire connection on the solenoid is the highest, most difficult to reach one, naturally.)

Good luck

Jerry M
'78 SC

[superglide]

Doc G; thanks. I didn't think that the engine could be frozen, but when the unexpected, unexplainable (at the time) happens, I revert to the belt-and-suspenders approach....

[superglide]

Thanks, Jerry. Some of my long-lost automotive theory is coming back to me now... the last time i was faced with this thorny issue, I was using a screwdriver to start my VW Bus, in college, due to the lack of funds for a new starter. I certainly hope that this is the problem, and I'll report back to you guys when I find out...
Best Wishes,
Andy

[911pcars]

You can energize the starter w/o the fireworks display. Merely use a jumper wire and momentarily connect the battery terminal on the solenoid to the solenoid terminal (yellow wire). This is the same effect as using the ignition switch. Do this with the ignition OFF. You want to test the cranking system, not necessarily start the engine and all that goes with it, especially with you under the car.

Sherwood

[superglide]

Thanks, Sherwood. I'll be giving that a try when I get home this afternoon.
Happy Motoring,
Andy

[David E. Clark]

There is an article in the tech articles section called Starter System Troubleshooting by James K. Thorusen which deals with 914s but which I find pretty helpful no matter what type of car you have.


Motor Age also ran an article in their November 2004 issue called The starting system troubleshooting guide which should be very helpful. Good Luck.

[superglide]

Much later: well I had to go out of town to visit a jobsite of ours, took longer than I thought it would and finally got to use the troubleshooting tips last weekend. With a new battery, clean groundstrap(s), and all the correct whines and hums front & rear with the key turned -nothing happening at the starter but a faint click. When I jumped the terminals as suggested. again nothing. Absolutely dead back there. I'm betting on a new starter / solenoid, though it hasn't given me a whit of trouble for 8 years. Any other guesses, before I pull that nasty double-joint-needing ***** out of the car? Thinking of replacing it with one of those compact hi-torque starters.

[Jim Savage]

This may sound stupid, but I would check the battery for the correct voltage before I started replacing things. I know you said it is a new battery but was it charged before installing? Might be a dead battery staight from the shelf. Strangers things have happened.

Did you make sure the engine turns and is not frozen?

Worst case is to remove the starter and have it checked by your FLAPS.

[superglide]

Jim, new batt, charged @ 2amps over night, reading close to 13 volts. Lights are bright, engine turns fine by hand. what I'm really complaining about is changing the starter in less than wonderful circumstances like on the grass, in the weather, rear bolt too far away to even feel with the fingers, much less see it, bla bla whine whine, etc.

Guess I gotta do it, though, and the only way around it is through it, as my D.I. used to say... Stay tuned, more to follow.
Happy Motoring,
Andy

[911pcars]

Open circuit voltage of 13 volts is one thing.

Do this. Measure the battery voltage when the switch is in the crank or start position. The battery voltage should drop during cranking, but stay above 9 volts under a normal starting load.

If it's <9 volts, the battery is NG (no capacity despite 13 volts). 8 AA batteries in series = 12 volts, but same dilemma, no capacity.

If the battery voltage drops to 9-10 volts, but the starter is still quiet, I would suspect a faulty starter motor. Current is entering the windings and going to ground, but that's all. No oomph.

If the battery doesn't waver and stays at 12-13 volts (less voltage needed to energize the solenoid), then the solenoid isn't connecting battery to starter motor (open circuit). You might even hear the solenoid go "click". Not good enough.

Since you have some loathing to remove the starter (I don't blame you), you can perform an additional test. With a voltmeter, check the voltage drop between the battery terminal on the solenoid and the one on the starter motor. Fashion some way of attaching the VM leads onto the battery terminals, crank engine, then record the voltage drop. If the solenoid connection is good, the VM drop will be negligible; ~.1 volt. If the solenoid connection is NG, the VM will display 2-3 volts indicating a poor connection on up to 12 volts for a completely open (not connected) circuit.

If so, now you can get the grass stains and remove the starter.

Hope this helps,
Sherwood

[superglide]

Sherwood and Ron,
many thanks for the more detailed info; I've got a few more connections to remove & ckean at the starter. did the groundstrap @ the trans and those things sure hold grease and crud. I must've lightened the car by 10lbs cleaning it.

I'll check & clean the starter connections, and perform the electrical testing that Sherwood suggests. Only problem is there's only one of me but perhaps I can rig up some extension wires to the VM, and check it from the cockpit. see what happens, & report back here.

if bark comes to bite; are ther any tricks for removing the upper hidden nut on the starter, other than determination? Is it even a 15mm nut as the lower one is?
Best,
Andy

[Gunter]

The trick is fulcrum, leverage and to hug your transmission.
Prepare a light, secure the car, put on safety goggles to keep the dirt out of your eyes, climb under and hug the transmission.
Feel for the top fastener. Most likely it's a 10mm barrel nut unless someone changed it over time. Limited space requires creative application of wrenches, extensions etc.
Don't bust your knuckles, apply the necessary force with caution.

[911pcars]

[b]"Only problem is there's only one of me but perhaps I can rig up some extension wires to the VM, and check it from the cockpit. {'b]

Andy,
You can energize the solenoid at the starter w/o the key. You probably don't want the engine to start accidentally.

With a jumper wire or an official remote starter switch, momentarily connect the battery terminal on the solenoid to the solenoid terminal holding the yellow wire (the same yellow wire the ignition switch connects to source voltage).

I agree with Gunter for removing the top starter nut. Stacking 3/8" drive extension(s) (2 to 2 1/2' long), will give you room to rotate the ratchet handle with leverage.

Hope this helps.

Sherwood

[superglide]

thanks, Doc. as soon as this current weather system blows through, I'm going to go hug my trans... Seriously, there's always a good trick or two that only those who've done it can offer. And they're not found in the Bently manual, either.

Sherwood, thanks as well. I've tried the remote starter switch and absolutely nothing happens. The lead extensions are necessary for my volt meter so that I can try the voltage tests you've suggested.

I'll use whatever combo of extensions, swivels, etc necessary to get that starter off, you can count on it. my major handicaps are large hands, a big belly, and not enough elbows on each arm... Progress report(s) to follow
Best Wishes,
Andy

[Gunter]

Andy:
The main connection on the starter is black (Battery) and red (Alternator) You should have 12V there.
The Solenoid has a yellow wire coming from the ignition switch.
Crawl under the well-secured car with a light.
Gears in neutral, ignition off!
Pull the yellow wire off the Solenoid,
Connect a short heavy wire from the starter connection to the spade on the solenoid where the yellow wire normally sits.
The solenoid should click, starter engages, engine turns.
Are you saying that there is nothing?
If you cannot get the solenoid/starter to work with this short-cut, the problem usually is:
A bad battery, or the black wire from the battery is not bringing full power, or the ground straps are not grounding back to the battery.
Next would be a full battery right under the car, with a heavy wire from the +terminal to the starter, another wire from the -terminal to the starter body for ground. Then bridge from the +starter connection over to the solenoid where the yellow wire normally connects.
If that doesn't work, the starter/solenoid is faulty.
With a rebuild starter, it is still possible that the yellow wire, and/or the electrical portion of the ignition switch is getting old.

[CliffBrown]

Sounds like you're taking all the right moves but confirm that you have cleaned the terminals at the battery, both the battery post and the cable terminals. Clean and tighten the battery ground strap at the chassis.

I'm suspecting your battery condition or electrical cables. Check the battery voltage for 12.8 after the battery charger has been disconnected from the battery for at least 2 hours. Take your VOM into the cabin with you and hook it up to something like the cigar lighter, try to start the motor and monitor the battery voltage, your looking for the voltage to return to 12.8 or so after releasing the ignition switch to the start position. Something as simple as a bad ground connection can mimic the exact conditions you're experiencing. Make sure the black cable at the starter is clean and tight. Try using a different battery or hookup jumper cables.

Starters do fail but they usually give warning signs before a complete failure.