Car starter stuck. Can you reverse polarity for a second to free it up?
Im looking to buy a car that has a bad starter. Its a gamble that im willing to risk, since its so cheap
The starter is very difficult to access. Cant even hit it with a rod.
So my question is, if i can easily access the starter wires up top, and i have a separate power supply, can I reverse polarity to it for a second or two just to free it up, hook it back up to normal and see if that helps me start it up?
Ive never heard anyone do this, so im very curious.
- Anonymous7 months agoFavorite Answer
Nope sorry. The current in a starter motor goes through both the armature and the field coils. They're arranged for the magnetic fields to be in the right relationship and simply reversing the polarity outside the motor doesn't change the relationship between the two. To reverse the rotation you'd need to reverse the polarity going to the field coils or to the commutator but not both and to do that you'd need to get inside the starter. What you can do is try rocking the vehicle. If the bendix gear is stuck in the flywheel it might break loose if you're lucky. Also be sure the battery is fully charged. I've seen starters get stuck because the bendix was engaged when the voltage dropped too low to continue turning the starter.
- The DevilLv 77 months ago
When my starter stuck and would not turn off, it was because the Bendix drive contacts welded themselves together. I replaced the starter and drive, since the unit became hot enough to light paper on fire and i didn't want to trust it after simple clean and lube, plus after 20 years I wanted new parts.
- M.Lv 77 months ago
Start with your application.
Disclose it to us.
Year, brand, engine size.
How do you figure that it is "stuck"??
- Road warriorLv 47 months ago
You can but it will make no difference. Will still turn same direction. The way commutator is oriented to armature and field, it will only turn say CW as viewed from the commutator. Or CCW if a gear reduction type..
You can go ahead and try it, But, be Sure to remove all wires from starter.. Remove ground from battery. Use an external battery. Simply reversing while connected can blow alternator diodes (if fuse/fusible link doesn't go) and everything electronic on car that happens to be always on, like memory to ECM and radio.
Use WD40 to free it up.
I Sympathize with an impossible to access. starter. My sister-in-laws Honda had one easy to drop out But that last bolt needed a bit of wire to get it in there. then, a turn by hand. Pull to remove wire then use socket wrench.Source(s): Electronics tech 40 years, fixed motors, generators, cage/'sickle electrical Dad was E/M in USN 20 years plus 10 years Civil service , maintaining ship electrical.
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- thebax2006Lv 77 months ago
That's not going to work jojo.
- Anonymous7 months ago
WD40 on the Bendix drive should solve the problem if you can remove the starter. See if it is accessible from under the car. If so use ramps. As said, rocking the car in a low gear usually frees it, but only temporarily.
- ErikLv 77 months ago
That sounds like something from Star Trek. Why not just replace the starter? It's not a super expensive repair.
- BillLv 67 months ago
nowwhat good would that do
if you were successful-which you won't be- you are buying junk that will do the samething again
GO find a better deal and pass on anything with problems
- jimanddottaylorLv 77 months ago
A fellow sold me a car with a bad starter. He had the starter out in the trunk . A new one was coming in 2 weeks, but it was the end of the month and he was moving. I bought the car (good deal) and when the starter came, I crawled under the car to install it and discovered that it had thrown a rod and 1/2 the engine block was missing.
You could disconnect the car battery, and run separate jumper cables to the starter, bypassing the rest of the car electronics. But remember there may be more problems
- JoeLv 77 months ago
No, you can't.
The ground connection for the starter is through the engine block, and the vehicle chassis. You'd have to turn the whole car into a "positive ground" system - and then, you'd likely blow out the alternator diodes and the computer.