Starter issue |
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Starter issue |
jrblackbox |
Jan 25 2020, 07:01 AM
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#1
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Member Group: Members Posts: 285 Joined: 8-September 15 From: Easton, CT Member No.: 19,140 Region Association: None |
Ok, so I changed out the starter in my 6 with another starter I had collecting dust. Now upon turning the key there is a "delay" of a second or 2 before the car turns over. So when I turn the key I can hear the fuel pump come on, then the delay, then the car will crank. did i put the wrong starter in? Or do I need a high torque starter or??
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Tdskip |
Jan 25 2020, 08:03 AM
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#2
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Advanced Member Group: Members Posts: 3,686 Joined: 1-December 17 From: soCal Member No.: 21,666 Region Association: None |
Odd - maybe a lot of resistance in the wires?
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Superhawk996 |
Jan 25 2020, 10:31 AM
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#3
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914 Guru Group: Members Posts: 5,891 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Odd - maybe a lot of resistance in the wires? Yes. Very good intuition! (IMG:style_emoticons/default/smilie_pokal.gif) 5 seconds sounds and awfully long delay to be created by an LR series circuit alone though. There is a minor delay is created by an LR L=Inductor (i.e. motor) R=Resistance series circuit. The time delay depends on the relative values between L & R. In all practicality, what is probably happening is that you are getting a large voltage drop across high resistance starter motor cables that actually limits the voltage that the starter sees. As an alternatate possibility, you could have a bad commutator sector that isn't energizing properly and it takes some time for the starter motor to turn in response to the weaker than normal stator winding magnetic flux. Once the motor rotates that little bit and makes a better connection to the next commutator segment, the motor begins to spin faster, gains momentum and from there has enough intertia to "skip" over the bad segment. Be sure your have fresh battery cables and a good (i.e. zero ohm) ground between the transmission and the body and a zero ohm cable between the battery positive and the starter solenoid. The OEM ground strap is often missing, or damaged leading to high resistance to the starter. If this ground strap is missing the clutch cable usually becomes the ground. The clutch cable is not a very good ground since it is stranded steel wire, and the high current that is trying to be drawn though the clutch cable leads to slow cranking, and, will eventually lead to catastrophic failure of the clutch cable when you least expect it. Ask me how I know . . . . (IMG:style_emoticons/default/happy11.gif) Basics of the LR circuit time delay are in link below. https://www.electronics-tutorials.ws/induct...r-circuits.html |
jrblackbox |
Jan 25 2020, 11:39 AM
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#4
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Member Group: Members Posts: 285 Joined: 8-September 15 From: Easton, CT Member No.: 19,140 Region Association: None |
Odd - maybe a lot of resistance in the wires? Yes. Very good intuition! (IMG:style_emoticons/default/smilie_pokal.gif) 5 seconds sounds and awfully long delay to be created by an LR series circuit alone though. There is a minor delay is created by an LR L=Inductor (i.e. motor) R=Resistance series circuit. The time delay depends on the relative values between L & R. In all practicality, what is probably happening is that you are getting a large voltage drop across high resistance starter motor cables that actually limits the voltage that the starter sees. As an alternatate possibility, you could have a bad commutator sector that isn't energizing properly and it takes some time for the starter motor to turn in response to the weaker than normal stator winding magnetic flux. Once the motor rotates that little bit and makes a better connection to the next commutator segment, the motor begins to spin faster, gains momentum and from there has enough intertia to "skip" over the bad segment. Be sure your have fresh battery cables and a good (i.e. zero ohm) ground between the transmission and the body and a zero ohm cable between the battery positive and the starter solenoid. The OEM ground strap is often missing, or damaged leading to high resistance to the starter. If this ground strap is missing the clutch cable usually becomes the ground. The clutch cable is not a very good ground since it is stranded steel wire, and the high current that is trying to be drawn though the clutch cable leads to slow cranking, and, will eventually lead to catastrophic failure of the clutch cable when you least expect it. Ask me how I know . . . . (IMG:style_emoticons/default/happy11.gif) Basics of the LR circuit time delay are in link below. https://www.electronics-tutorials.ws/induct...r-circuits.html Not 5 seconds, more like a second or 2 only. Definitely longer to crank since swapping starters. |
Superhawk996 |
Jan 25 2020, 01:02 PM
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#5
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914 Guru Group: Members Posts: 5,891 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Not 5 seconds, more like a second or 2 only. Definitely longer to crank since swapping starters. Sorry, my bad. Don't know how I got to 5, you clearly mentioned one or two now that I re-read it. Follow Tom's advice for the quick check of "jumpering" the solenoid control to the Battery + lead. |
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