Engine 'run-in'

• jae

  11 Sep 03, 10:55

  hi guys, i have a qn here...what does it mean, and how much distance to clock before the engine can be said to 'run-in'?
• -x-

  11 Sep 03, 17:15

  hi,
  
  for jap cars, normally the first 1000km is the run-in period, tho some will stretch it to 3000km.
  
  -x-
  
• Si|verGer

  13 Sep 03, 17:50

  Originally posted by jae:

  hi guys, i have a qn here...what does it mean, and how much distance to clock before the engine can be said to 'run-in'?

  think when u buy e car e person will tell u.. den when u run in i tin cant rev beyong hw many rpm..
  den after u run in liao u will bring it 2 e workshop or wad 2 change e engine oil ,etc..
• jae

  15 Sep 03, 17:58

  thanks for the reply, i know the procedure for engine run-in...
  not to rev too much etc, but i'm asking more in terms of the technical side, as in 'why do we need to run-in engine' and not 'how to run in engine'.
• bismarck

  15 Sep 03, 19:54

  Originally posted by jae:

  thanks for the reply, i know the procedure for engine run-in...
  not to rev too much etc, but i'm asking more in terms of the technical side, as in 'why do we need to run-in engine' and not 'how to run in engine'.

  this is because when the factory produces the engine parts, the bore of the cylinder and the piston, they try to make them fit as nicely as possible. but it is impossible to make a perfect seal,so what happens is that the diameter of the bore and the size of the piston is something like can fit properly but not the optimum fit.
  so when the engine starts, the pistons 'grinds' aganist the cylinder wall. they sort of 'sand' or 'smoothen the surfaces, something like using sandpaper to smoothen a piece of wood. then the tiny metal particles are carried by the lubricants.
  
  the idea of running-in is to achieve a optimum seal between the cylinder wall and the piston with a thin layer of lubricant between them.
  when there is a very good seal, the gases inside the chamber would not escape and no energy is lost this way.
  
  anyway the reason why there is a air filter ( and oil filter ) is to remove as much solid particles before pumping into the engine. because if there is, then it's byebye for yr engine.
• jae

  15 Sep 03, 21:45

  great to know that. thanks man, appreciate ur post.
• bismarck

  16 Sep 03, 18:17

  Originally posted by jae:

  great to know that. thanks man, appreciate ur post.

  thank god my post was understoodable by others.
  anyway i was afraid it was too technical.well my dad told me all these and he inadvertently sparked my interest in engine mechanisms and cars.
• Si|verGa|

  17 Sep 03, 18:52

  Originally posted by bismarck:

  thank god my post was understoodable by others.
  anyway i was afraid it was too technical.well my dad told me all these and he inadvertently sparked my interest in engine mechanisms and cars.

  i understood it as well! thx! it was v clearly explained..