KA Starter problems, need help desperately

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Silly40
Posts: 2
Joined: Sat Jan 28, 2017 12:15 pm
Car: 1991 nissan 240sx sil40

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(Apologize for the long story) I had the car down to replace injector o-rings, after that was over the starter decided to quit on me so I threw in one I had laying around. On the first start up I didn't notice but the cable that connects to the positive battery terminal was touching one of the metal coolant lines and shot sparks/etc, so I went back and redid, triple checking nothing was touching. Wouldn't crank. So I just decided to buy a new starter, now all I get is a grind followed by a single loud clunk. Could a weak connection/low voltage to the starter (since I may have fried that wire when it grounded out) cause that? The only other thing I can think of is the flywheel missing teeth and I'm hoping not to have to deal with that in this weather haha. Thanks in advance for any insight


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Hijacker
Posts: 15759
Joined: Wed Aug 13, 2003 4:57 am
Car: '92 240sx Convertible
'94 F-150
Location: Fredericksburg, VA

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Things that could be wrong:

Bad battery. These cars don't have a battery protection fuse like newer cars do, so when you short out a direct connected cable, it can possibly short out a plate inside the battery

Burned cable. A burned through insulation could be making contact with something it shouldn't, dragging the system down.

An easy check on the battery is to take a DMM to the terminals and see what you get. Typically, you should see around 12.5 V with the vehicle off. If you see less, then you have some plates that decided to fuse together, and you've lost the volts those plates offered. If you have sufficient voltage, have someone crank the car and check what the voltage sags to. If it goes way low, then you know something is dragging the system and keeping the start from cranking properly.

Silly40
Posts: 2
Joined: Sat Jan 28, 2017 12:15 pm
Car: 1991 nissan 240sx sil40

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Hijacker wrote:Things that could be wrong:

Bad battery. These cars don't have a battery protection fuse like newer cars do, so when you short out a direct connected cable, it can possibly short out a plate inside the battery

Burned cable. A burned through insulation could be making contact with something it shouldn't, dragging the system down.

An easy check on the battery is to take a DMM to the terminals and see what you get. Typically, you should see around 12.5 V with the vehicle off. If you see less, then you have some plates that decided to fuse together, and you've lost the volts those plates offered. If you have sufficient voltage, have someone crank the car and check what the voltage sags to. If it goes way low, then you know something is dragging the system and keeping the start from cranking properly.

I've now got the car to crank, but after about 5 seconds of cranking it stops and won't do anything but click once until I leave it sit for a few minutes. The battery is brand new, I've checked voltage and it's good. Thinking it may be the ignition I wired a push-start button and I still just get cranking for about 5 seconds, then nothing. I checked the voltage to the starter with the key on and got a solid 12.5 volts. Really starting to feel lost here haha. I haven't checked voltage while the car is cranking so I'll see how that works out

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Hijacker
Posts: 15759
Joined: Wed Aug 13, 2003 4:57 am
Car: '92 240sx Convertible
'94 F-150
Location: Fredericksburg, VA

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Expect the voltage to dip when the car is cranked as the starter is a big drag on the electrical system. It's been a while, but if I'm remembering right, it shouldn't dip below 9.5 V. If it does, then you definitely have an issue. Since you mention the car will crank over for a solid 5 seconds or so, and then you get nothing, I'm leaning towards this being a battery issue.

When doing the crank test, be sure to measure the battery terminals. You'll get a clearer picture as to what is happening to the battery.


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