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Tue Jun 09, 2009 3:57 pm

Should I be getting continuity between the B+ on the alt. and ground while the car (type 1) is not running?

Wed Jun 10, 2009 6:58 am

With the battery hooked up.... :shock:

Wed Jun 10, 2009 8:06 am

I gotta ask why........ Does alternator work??? OR you trouble shooting possible alternator problems...

IF you have alternator wired up and are testing for continuity you have whole cars electrical system hanging on the connection, sure you are going to have continuity readings...

Dale

Wed Jun 10, 2009 2:20 pm

I am troubleshooting a starter failure and came across this odd continuity between the B + on the Alternator and ground while the battery is hooked up.

My main battery cable goes from + to the starter then to the alternator, but that would mean that it is shorting out?

The starter will not work while installed but does work on the bench. All the wiring is new and the car has been starting fine, all of a sudden the starter stopped working.

I checked the starter bushing and it looks good but can you tell just by looking at it?

I was also considering something like the alternator going bad and causing a short that prevents the starter from operating, does that sound plausible?

Thanks.

Wed Jun 10, 2009 2:29 pm

Nicksan wrote: I am troubleshooting a starter failure and came across this odd continuity between the B + on the Alternator and ground while the battery is hooked up.

My main battery cable goes from + to the starter then to the alternator, but that would mean that it is shorting out?

The starter will not work while installed but does work on the bench. All the wiring is new and the car has been starting fine, all of a sudden the starter stopped working.

I checked the starter bushing and it looks good but can you tell just by looking at it?

I was also considering something like the alternator going bad and causing a short that prevents the starter from operating, does that sound plausible?

Thanks.

What are you using to test continuity? If you're using a light to ground it should be lighting up when you touch B+. If you're using a digital continuity tester on a digital multimeter, it will probably still read continuity. Every point of every circuit is connected to every other in some way, otherwise its not a circuit. You're getting a connection that goes from the B+ post, down the wire to the starter, then battery, then ground. Thats all a closed circuit when you bridge your instrument from ground to B+.

Wed Jun 10, 2009 2:58 pm

Cuog wrote:

What are you using to test continuity? If you're using a light to ground it should be lighting up when you touch B+. If you're using a digital continuity tester on a digital multimeter, it will probably still read continuity. Every point of every circuit is connected to every other in some way, otherwise its not a circuit. You're getting a connection that goes from the B+ post, down the wire to the starter, then battery, then ground. Thats all a closed circuit when you bridge your instrument from ground to B+.

I am looking for other reasons to my starter problem before I go ahead and take out the ignition switch and attempt tp replace the starter bushing.
How does one tell if the starter bushing is good or not?

Wed Jun 10, 2009 4:49 pm

I might be looking at your wiring first. With the starter installed try cranking with the key. Does it make any noise at all? If not check your wiring. If you are able to cross the terminals at the starter and it cranks over it is most likly mis wired or the switch is bad. A bad bushing is "not round anymore" they are made of a brass alloy and you can usually see where they have worn away. If you end up needing to replace your starter use one for a Porsche 914 It is self supported and does not need the bushing just plug it in and go.

Wed Jun 10, 2009 5:16 pm

66 12volt wrote: I might be looking at your wiring first. With the starter installed try cranking with the key. Does it make any noise at all? If not check your wiring. If you are able to cross the terminals at the starter and it cranks over it is most likly mis wired or the switch is bad. A bad bushing is "not round anymore" they are made of a brass alloy and you can usually see where they have worn away. If you end up needing to replace your starter use one for a Porsche 914 It is self supported and does not need the bushing just plug it in and go.

No, it makes no noise at all when I turn the key, I have jumped it while installed and it does not do anything. I removed it and bench tested it and it works fine on the bench.
The bushing looks good. I have not removed the ignition switch to test it because it is new, that is my next step. Even though the switch is new I am hoping that is the problem. lol.

Wed Jun 10, 2009 5:21 pm

Nicksan wrote: ...(snip).....

I was also considering something like the alternator going bad and causing a short that prevents the starter from operating, does that sound plausible?

Thanks.

NO....

If what you describe were true, it would be a dead short and it would burn up your wiring to alt and kill battery...

IF you jump starter (in car) from hot terminal (top solenoid terminal - one with + battery cable) to terminal 50 (push-on connector on solenoid) does it engage? (that would be push on terminal on transmission side of solenoid)... Also check ground side of battery/cable, is it connected to chassis and is there a ground strap from chassis to trans or is ground cable connected directly to trans?

Also starter from AUTO TRANS Beetle is self supported and a good option if you have to replace starter...

Dale

Wed Jun 10, 2009 5:54 pm

Dale M. wrote: Nicksan wrote: ...(snip).....

I was also considering something like the alternator going bad and causing a short that prevents the starter from operating, does that sound plausible?

Thanks.

NO....

If what you describe were true, it would be a dead short and it would burn up your wiring to alt and kill battery...

IF you jump starter (in car) from hot terminal (top solenoid terminal - one with + battery cable) to terminal 50 (push-on connector on solenoid) does it engage? (that would be push on terminal on transmission side of solenoid)... Also check ground side of battery/cable, is it connected to chassis and is there a ground strap from chassis to trans or is ground cable connected directly to trans?

Also starter from AUTO TRANS Beetle is self supported and a good option if you have to replace starter...

Dale

Yea, I figured it would burn up the wiring or melt something else since nothing is fused from there-on.....
I get nothing when I jump the alternator while installed but It does work when removed.
I have a ground strap directly from the body to the tranny. I have good ground continuity between the starter, tranny, alternator, pan and, body.
This starter problem just appeared out of nowhere...... Using a Auto Trans sound good but I have two working standard trannys... Errr.... Working on the bench. LOL.

Wed Jun 10, 2009 7:02 pm

Nicksan wrote: Dale M. wrote: Nicksan wrote: ...(snip).....

I was also considering something like the alternator going bad and causing a short that prevents the starter from operating, does that sound plausible?

Thanks.

NO....

If what you describe were true, it would be a dead short and it would burn up your wiring to alt and kill battery...

IF you jump starter (in car) from hot terminal (top solenoid terminal - one with + battery cable) to terminal 50 (push-on connector on solenoid) does it engage? (that would be push on terminal on transmission side of solenoid)... Also check ground side of battery/cable, is it connected to chassis and is there a ground strap from chassis to trans or is ground cable connected directly to trans?

Also starter from AUTO TRANS Beetle is self supported and a good option if you have to replace starter...

Dale

Yea, I figured it would burn up the wiring or melt something else since nothing is fused from there-on.....
I get nothing when I jump the alternator while installed but It does work when removed.
I have a ground strap directly from the body to the tranny. I have good ground continuity between the starter, tranny, alternator, pan and, body.
This starter problem just appeared out of nowhere...... Using a Auto Trans sound good but I have two working standard trannys... Errr.... Working on the bench. LOL.

How do you jump a alternator...

If it works on bench (which you should actually not do because shaft is unsupported and armature will drag on field windings), it has to work in car.....

Something ELSE in car is broken.... Look else where, its not the starter....

You are relying to heavily on continuity tests.... Throw meter away and use good engineering principle...

Dale

Wed Jun 10, 2009 8:23 pm

Nicksan, I'll post here rather than go back to the other post. If memory serves you said the starter bench tested OK. This can only mean you have a wiring problem or ignition switch, or battery problem.
Things to check AGAIN.
All grounds----battery negative to frame and strap from frame to transmission.
All HOT------Battery positive to large post on solenoid------Battery positive to Ignition switch and ignition start position to inboard spade connector on solenoid.
Is the battery charged? Are you sure? :lol:
As I recall you said there was no click or noise at the starter when you turned switch to the crank position.
BTW, if you need to remove the starter bushing you can screw a 7/16 X 14 TAP into it and it will come out. This isn't your immediate problem though.
Marvin

Thu Jun 11, 2009 7:20 am

It would be best to get a digital volt ohm multimeter and check voltage in battery and at B+ terminal. You should have 12.6 volt's surface charge on battey, and you can also get a load tester to check to see if battery is good under load.

If you do not have the 12 volt's with the miltimeter you will need to charge battery. A test light will not tell how many volt's you have it will only tell you that you have some voltage.

Good luck
Leland

Thu Jun 11, 2009 7:41 am

You did say jumping the alternator? Perhaps you meant starter. Just to be clear, a starter cannot be engaged at the alternator. It is done "as Dale described" at the starter. When crossing the terminals you will get at the very least a large spark. If not you are not getting power to the starter. Be sure you have the the correct spade connected. Load test your battery. Even a dead battery may read 12 volts on a meter. A load test will determine if the battery is good or bad. And again check the the pos and neg batt cables and connections.

Thu Jun 11, 2009 2:10 pm

LOL, Yea I meant I jumped the starter, not alternator....... Sorry for the confusion.