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1968 Mustang starter turning too slow, bad starter?

Old 07-14-2014, 06:50 PM
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knuckless
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Default 1968 Mustang starter turning too slow, bad starter?

Long time since I've logged on but you guys have always been a great help.

So I've been driving my 68 mustang everyday to work since the summer started and have not had an issue with it until the past week or so and then today the hammer dropped.

Last week I noticed I was getting a weak start from my start, but then my engine would fire a second later and it wouldn't matter. Today I pulled into work to pick somethings up and then went back out to my car and the same thing happened, this time it the battery died. It was a weak start, then solenoid clicking. I tried turning the ignition again, and nothing. I had one of my employees pull his car over to jump me and I was literally getting no power, as if either I or he had bad connections. Finally got a good connection and the car started up no problem. I drive it 30 minutes and park it for 5 hours before jumping back in and that car starts fine on the first turn of the key.

I drive it another 30 minutes back home and let it sit for about 3 hours then jump in to start it and all I get is the starter turning very very slow and very very weak. I take out my voltage meter and I'm at 11.70 volts on the batter and on the batter cables so I know my cables are getting a good connection. The solenoid is fine and working obviously if the starter is turning, its just turning so very weak it won't fire the engine.

Did my starter get heat fried or something? After cranking the car a few times my solenoid is red hot and the cable to the starter is as well. Not sure if this has anything to do with the issue.

So basically I have good voltage, good connections (although I have not check my connection to the starter yet as I am in khakis and a polo right now) but my starter is just very weak and won't turn fast enough to fire the engine. I have been cranking it for the better part of a minute or so and still have good voltage in my battery so I know it can't be a bad battery. I'm not sure how exactly to check the connection to the starter since I can't engage the starter while under the car.

Appreciate any help.
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Old 07-14-2014, 07:55 PM
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update:

I got it started because I finally gave in and decided maybe the amps are too low. So I jumped it with another car and it fired immidiately. So apparently my battery could be shot again.

Idling I am at 11.5 volts, and it jumps to 11.7 with a little bit of throttle. To me that seems extremely low. New 80 amp alternator was installed during the winter so I know thats good, and the the fact it jumps a few volts when I give it some throttle tells me its getting a charge, as well as the driving 30 minutes without it dying on me.
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Old 07-15-2014, 02:44 AM
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dawson1112
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quite frankly you should be seeing about 13-14.5 volts at idle . If you are seeing less than 12v at idle then your not keeping your battery charged. This leads me to believe that your voltage regulator is shot or you got a bad alt.

Starters pull more amps when they get hot due to resistance. A hot starter has more resistance than a cold starter. This would strain a weak charging system.

A bad starter on an other wise good charging system would have the same effect, as it heats up resistance builds to the point where it pulls more amps than the battery can handle.
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Old 07-15-2014, 05:21 AM
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67mustang302
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Starters pull fewer amps when hot, and as a result crank with less power. The charging system has nothing to do with starting, charging problems and starting problems are 2 separate problems. Though a bad charging system can lead to a drained battery which will affect starting.

You need to look at alternator, voltage regulator or charging system wiring.
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Old 07-15-2014, 07:52 AM
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Well since the alternator is fairly new and the voltage regulator was replaced a while back I'll take a look at the regulator for now.
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Old 07-15-2014, 10:28 AM
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Sounds like a bad cell in the battery. How old is it? If it is a year over warranty, then it is probably shot. Lead drops out of the plates and falls to the bottom of the cell. Eventually it build to the point where it will short the cell. idling at 11.5 volts means that there is a load on the system which translates usually to either a short, heavy usage such as lights and AC or a bad cell.
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Old 07-15-2014, 11:37 AM
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battery is about 2 years old, no lights or any electric was running.
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Old 07-15-2014, 03:35 PM
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Unless you have a total garbage battery, it shouldn't be bad after 2 years (unless you cycle the battery really hard, like only drive 10-20min between each start).

Get the battery tested to see if you have a problem. If you can't get batteries to last, you have a charging system problem. If the battery tests ok (after they charge it) then it's a charging system issue (which can include wiring).
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Old 07-16-2014, 09:21 PM
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hello;

your battery is likely junk after sitting 2 years.

take it to most any parts store for free load testing.
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Old 07-17-2014, 12:06 PM
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Originally Posted by dawson1112
quite frankly you should be seeing about 13-14.5 volts at idle . If you are seeing less than 12v at idle then your not keeping your battery charged. This leads me to believe that your voltage regulator is shot or you got a bad alt.

Starters pull more amps when they get hot due to resistance. A hot starter has more resistance than a cold starter. This would strain a weak charging system.

A bad starter on an other wise good charging system would have the same effect, as it heats up resistance builds to the point where it pulls more amps than the battery can handle.
+1 on alternator or regulator. One of them are bad. If alterntor switch to 1 wire and loose the regulator
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