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The guy who sold me the car told me he had a lot of trouble previously with alternators. He went thru 2 re-builds and a new alternator before the problem seemingly corrected itself. When I inherited the car, the wire from the battery to the alternator broke off and dropped touching the body and draining the battery. Since the battery wasn't mine, I replaced it with a new one a month ago, I replace the broken wire and terminals and all was well. Until tonight in the grocery store parking lot. It wouldn't turn over. The guy parked next to me gave me a jump start and I was on my way. I shut the car off when I got home, and tried to turn it over and it was the same thing.
Does this sound like the alternator? If so, why is this brick eating so many alternators? Perhaps, for costs sake, it's time to retire the car and move on. I fear it could be a wiring harness issue, and I definately don't have the money for a harness or the labor involved to install one.
-Todd
Temporarily peeved at my 244.
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Canadian -'85 244 GL from Vancouver
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I have had new brushes twice in 18 months on my brick. No big deal, $20 each time.
Compared to "new" alternators or cars, that's fine.
The wiring is something that requires attention on these cars, but you deal with that and you have metal that goes forever. Keep rolling.
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Stef (81 245 B21A SU M46 3.91) 327000km - in the garage for the winter, 81 244 BW55 3.31 on the road)
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The guy parked next to me gave me a jump start and I was on my way. I shut the car off when I got home, and tried to turn it over and it was the same thing.
This could be as simple as a bad connection at either battery terminal or the ground connection at the motor.
By "bad connection", I mean the internal surface of the terminal that actually makes contact with the battery posts — or the block ground.
The jump start works because the jumper cable usually bypasses these points when clamped to the terminal's external surface.
This could prevent voltage from leaving the battery to run the starter, AND prevent alternator voltage from entering the battery to charge it.
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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
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Well right now you have either a dead battery, or a bad connection to it or the starter. Take a look at those first. Then go buy a VOM ($20 at Sears). Start the car ( or is it start the car then go to Sears?) anyway, with the car running, put the VOM set to volts, on the battery. YOu should see about 14v. if not, bad alternator or wiring. If so, then you have charging (and another problem).
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744 & 745 16v 4+OD, 245 SE auto, 242Ti 4+OD, 745 8v auto (new), 245DL auto parts car
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If it is the thin Red wire going to te Gray Connector on the firewall, you can just cut and add a new wire and not go for the price of the entire harness if your funds are tight.
leave 2" of wire coming out of the connector so you can solder a new one to that existing wire.
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me
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Alternators are pretty simple things. There are three wires connected, belts tightness, brushes, and the more complex things like diodes and bearings.
Check the wires first - easiest after checking belt tension.
Ground wire runs from the case of the alternator to, usually, under a bolt head on the mountng bracket. Tug on the wire, it can look OK and be not.
Charging wire, fat red, from the B+ terminal to the starter. Runs in the under-engine-front harness. I've not encountered this one going bad. However, if a hold-down piece on that harness looses its rubber coating and abrades its way into the harness there could be a problem. Not of the type you are meeting. Check that one for continuity, and tight connections on both ends.
Exciter wire. This thin red wire connects to a spade lug on the alternator. It is the usual culprit. It is one of the four or five wiers from the gray connector on the firewall and is subject to the crumbling insulation problemm. It is in that under-engine-front harness, and the connector onto the alternator can go bad. Check carefully, tugging on the alternator connection.
When that wire goes bad, things happen depending on how it fails.
If the wire is grounded somewhere, the AMP light on the cluster stays on while engine is running.
If the wire is not connected to anything, the AMP light won't light up at all.
If the brushes are worn severely, the excitation may or may not work.
In any of the above failures the alternator will not charge.
So check the thin red wire and the brushes thoroughly. Watch the behaviour of the AMP light.
good Luck,
Bob
:>)
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The thin red wire from the battery to alternator... anyone know what gauge that is?
-Todd
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Canadian -'85 244 GL from Vancouver
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I'm sure it's a metric gauge size, but it's pretty thin, maybe approx. like our (U.S.) 18 gauge.
I had trouble with mine - broke in more than one place right behind the alternator.
If you can identify it where it comes off a terminal connection on the firewall, you can bypass the existing and run a lead straight from there to the alternator.
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Sven: '89 245, IPD sways, electric rad. fan conversion, 28+ mpg - auto tranny. 850 mi/week commute. '89 245 #2 (wifemobile). '90 244 (spare, runs).
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Thanks. I may try and replace that one myself.
Another thing upon further inspection of my alternator (as I have headlight and dashlight power, so it's probably the alt). I have a red wire wired up direct from the battery terminal to the first nut on the alt. There's NOTHING connected to the second nut, though it looks like there was as there's a O ring terminal attached to it. As well, down lower is a blue wire with an O ring terminal just hanging loose down there. I wondered if this originally was where the power from the battery was connected before it was re-done by the last owner. Hope that makes some sense.
-Todd
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Canadian -'85 244 GL from Vancouver
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If this blue wire hanging loose is the ground wire, then what may be happenning is sometimes there is a ground throught the body of the alternator (such as where the adjuster bolt connects) and sometimes not.
Get that ground wire connected. (and I still suggest you get a VOM)........
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744 & 745 16v 4+OD, 245 SE auto, 242Ti 4+OD, 745 8v auto (new), 245DL auto parts car
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My neighbor just boosted me and I let the car run at fairly high RPMs for about 20mins-30mins in case the battery was dry. I didn't figure it was since it's BRAND NEW but in case. I shut the car off and left it for a few then it worked fine. I've been to the store and back twice now and it's turned over each time. I'm wondering if the battery was drained, or perhaps whatever the issue with alternator was it's corrected itself. For now at least. Just to be on the safe side, I'm going to replace the wire from the negative lead on the battery to the alternator as it looks a little shakey in a few places.
Can a bad alternator actually cause a battery discharge?
-Todd
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Canadian -'85 244 GL from Vancouver
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This is how the alternator should be connected:
-Big Red wire to the larger 'post' on the back of the alt. at about the 1:00 o'clock position as you look at the back. This comes from under the front of the engine and runs back to the starter solenoid where it is bolted together with a very big wire going to the battery Positive post. This is the wire that carries the alternator's charging current to the battery.
-thin Red wire coming out of the same harness bundle as the big Red connects to the other 'upper' alt. terminal - usually a little spade connector.
-fairly thick Blue wire near the bottom of the alt. is the ground and without it the alt. won't charge the battery. It needs to be connected to the engine block, via one of the alt's mounting bracket bolts. Make sure its other end is solidly connected to that little screw/bolt on the back of the alt.
If the alt. is OK, this connection method (which is how it left the factory)will now charge your battery.
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Bob (son's 81-244GL B21F/M46, dtr's 83-244DL B23F/M46, my 94-944 B230FD; hobbycar 77 MGB, and a few old motorcycles)
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It should charge the battery if the wires are alright. Sounds like the loose blue one is the problem. It could be intermittently touching just enough to ground it sometimes and lure you into a false sense of security. Best thing would be to take all the alternator wires loose, including the ones to the starter and the battery, clean all the connectors, and fasten every thing correctly and securely. Just for the sake of peace of mind. I just read that your alternator is connected to your negative battery post. I can only hope that this was a typo. The big red wire should be connected to the positive battery terminal. That's why they ran it to the starter at the factory, electrically it's the same point in the system. If it actually is connected to the negative side of the battery it should be changed immediately.
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I'm not sure why it's connected that way, but it looks like a bypass maybe. So if this is incorrect, why has it run okay all this time? I'll definately look at the connections in the morning.
-Todd
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Canadian -'85 244 GL from Vancouver
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If it's connected from the alternator to the positive terminal of the battery, bypassing the starter, leave it that way. I think it would be a good idea to clean all the charging system's connections and do a continuity check on the wiring.
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