Can someone please explain to me what the purpose of bushing is in a motor and what would happen if it was not present?

  • I voted to close your question because it is unclear what you're asking. There are several moving parts in a motor. What exactly are you referring to? Commented May 16, 2016 at 19:16
  • 1
    @Darth_Vader Sorry I am not sure I fully understand your comment. I am referring to the bushing, which is part of the motor. If I could tell you more then that I would not be asking the question :). Commented May 16, 2016 at 19:19
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    What kind of motor? A bushing is just an insert that goes into one hole to make that hole smaller or to change the shape of the hole. It can act as a bearing, add threads to a hole, or even act as a suspension member. Your question as written is basically the same as What is a bolt and what would happen if it was missing..
    – JPhi1618
    Commented May 16, 2016 at 19:28
  • Bushing is a cheap alternative to a bearing.
    – Moab
    Commented May 16, 2016 at 19:37
  • Not many (IOW: none at all) bushings inside an engine ... absolutely none I can think of anyway. There are plenty of bushings outside of an engine, such as in the suspension and in a starter motor as @racefever points out. As stated, I'm going to have to put a closed vote on this question as well. If you'd like to talk about your question to clarify, please come to The Pitstop where you can ask all the qualifying questions you'd like to clarify this question. Commented May 16, 2016 at 20:34

2 Answers 2


Some people call plain bearings bushings

The etymology can be different based upon geography.

If you have a 'bushing' in your engine it can commonly refer to a crankshaft plain bearing or a connecting rod plan bearing.

Here is the wiki on 'bushing'.

A plain bearing that is missing out of an engine would be unusual. To remove a crankshaft plain bearing an engine would have to be torn down, the same goes for connecting rods. Sometimes these bearing can be accessed from the bottom of the motor via removal of the oil pan at the bottom of the motor.

The purpose of a plain bearing is to reduce space between the crankshaft and the engine crankcase so that lubrication can be delivered to this area and the crankshaft. The crankshaft would float on a cushion of oil between the crankshaft and the plain bearing. If there is metal to metal contact the engine will destroy itself.

I hope this provides a viable explanation to your question.


Bushings are used to hold the ends of the motor shaft aligned. The motor shaft goes into the bushing and spins inside of it. You can see the bushing and the shaft in this image and get a good idea of how it works:

motor bushing assembly

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