why would starter wire smoke?

[89lx2.3]

hi,

well i got my alternator/regulator/relay wiring issues all worked out (basically had to make a new harness out of bits from another mustang's harness). but when I tried to start the car I could hear the starter making a little bit of noise, but not turning, and not turning the motor at all. I tried cranking a couple times and then I smelled burning rubber. when I looked under the hood the wire that goes from the relay to the starter was smoking really bad. What the heck would cause this? The starter is new (i know it could still be bad, how can i test?) the relay must be good becasue its getting enough power over to that side to burn up a wire like that. i know the motor is not siezed becasue i pulled the plugs out and i can turn it by hand. could the starter have got bound up somehow and if so how can i reinstall it and not have this problem. any other ideas?
Thanks!

 

[67 GTA]

Is it making a clicking noise? If so, then your solenoid is the culprit. It will sound like it is coming from the starter when you are inside the car. This will make your wires get hot and melt. Could also be a loose ground,connection, or a weak battery. Try crossing out the posts on the solenoid with a screwdriver or a remote starter if you have one. If the solenoid is bad then it will "click" repeatedly or do nothing at all. If it turns over then check your connections from that point.

PS Sometimes wires will get hot and smoke because they are not getting enough voltage.

 

[D.Hearne]

Wires will also smoke an burn when they're too small for the amperage. Try bigger wires, both the ground and the hot from the battery to the solenoid and also from the solenoid to the starter.

 

[SuperDave]

Remove the starter and bench test it using a set of battery jumper cables. This will verify whether the starter is functional or not. The smoke is caused by excessive resistance, The normal cables may have deteriorated. (Yes, that happens ) You can also test the amperage draw of the stater.

 

[65StangBoy]

We had something very similar happen on the cougar we just bought. The starter was cranking really slow. After cranking for a while trying to start the engine the cable got so hot that it melted itself out of the solendoid. It was the starter going bad and drawing too much amperage. We replaced the starter and the solenoid and it turns over perfectly. Sounds like it could be a bad starter to me.

 

[Ford4Fun]

I would first test the resistance of the wire between the starter and the solinoid. A wire like that should have no resistance to it, if it has any I would suspect the wiring.

 

[SuperDave]

I would first test the resistance of the wire between the starter and the solinoid. A wire like that should have no resistance to it, if it has any I would suspect the wiring.

Just for the record, ALL wires have resistance even if they are in good condition. To overcome the normal resistance of the starter (about 250 amps), larger wires are used. The larger the wire gauge, the less the resistance given the same voltage.

(Ohm"s Law explains many electrical problems.)

 

[Gummi Bear]

(Ohm"s Law explains many electrical problems.)

Yes, however many folks have a difficult time comprehending what all those i's, e's, and r's mean. [/jab]

Likely the starter is junk. Even though it may be a new one, remanufactured units can be faulty right out of the box. Do like Dave suggested and bench test that sucker, if you don't feel comfortable doing it at home, most any auto parts store will do this for you for free.

 

[89lx2.3]

AND THE WINNER IS!!!

Bad Starter... tested out like SD suggested and its no good. I had actually thought about just testing it like this before but thought that it had to be a bad idea somehow so i didnt... now i just hope i can find that reciept or that pepboys will just let me exchange it. I know one thing for sure though, this time im testin it before i leave the store.

"SuperDave's timeless wisdom:
5- "Just because a part is "new" doesn't mean it is good: VERIFY it!""

Thanks for the help guys!

 

[D.Hearne]

Ask them if they'll replace ( free of charge) your burnt starter wires while you're at it.

 

[89lx2.3]

well, i guess i was wrong. I took it back today to get a new one and they tested it there and it worked fine... now i am confused, i hooked it up with jumpers to a good battery, + to the terminal on the starter and - to the body of the starter and i got nothing but some smoke off the ground connection, they hooked it up to their table and it worked fine. i am now suspecting my ground is no good or that the relay is not providing it with enough power. any other suggestions? how can I test how much power is getting through the relay (amps, volts, what should i test?) if i remember correctly i checked the resistance of the ground strap to the batt - before and got a 0 reading (should also be grounding through the body of the starter to the engine), ill check it again anyway.

 

[D.Hearne]

Just because a starter tests good on a bench, doesn't mean it's good. There's a vast amount of difference between testing it while free-wheeling and while it's under load, trying to turn the motor over. The problem with most store bought rebuilt starters is very few have had the field coils changed. These are what give it the torque to move the motor. Judging from what you've posted, I'd go back and replace the cables, both hot and ground, with larger ones,along with a new solenoid, and another starter

 

[SuperDave]

Agree with D.Hearne. Cables may "look OK" but still can have high resistance due to internal disintegration and corrosion. You might say that the cables age and with that the resistance goes up. Often, if you cut the insulation away from a suspect cable, it will corroded.

The end terminals on the cables should be throughly clean and should NOT (repeat NOT) have the cheesy "repair terminals" often used. A reistance test of the cables themselves may be revealing.

A multi-meter can tell you a lot about what is or is Not happening. A meter has many uses and may be had for about $10 (or more) at Radio Shack, Sears, etc.

 

[BullittStangV8]

well after reading this post, i think ive found the aswer to why my engine wont turn over. all it does is click-click-click over and over.no cranking at all. (and yes it is the selonoid doing it, as i put my handon it and felt it vibrating and heard it making the sound..) anyways where can i purchase a new seloniod, and what kind/compay do you guys suggest..?
Mike

 

[D.Hearne]

Any parts house will stock the solenoid. They're as available as the dirt in your backyard.