Important! : bearing clearances how ?

1. toxic Frequent Poster Joined: Mar 2007 Posts: 772

   #1 3rd January 2011, 13:53

   hi what i wont to know is about bearing clearances , i am thinking about putting in new pistons in and have read about plastigage why do you need this if they are for your car don't you just torque it down like the old 1s you just taken out. how is the bearing clearances work is it more you torque it down the less clearance you have ? would be good if someone could help thanks.
2. raunchz Saxperience Addict Joined: Jul 2005 Solihull / Bournemouth Posts: 14233 2015 Lapiz Blue Golf R

   #2 3rd January 2011, 13:57

   Plastigauge is normally used for bearing clearances

   1 user thanked this post: toxic
3. raunchz Saxperience Addict Joined: Jul 2005 Solihull / Bournemouth Posts: 14233 2015 Lapiz Blue Golf R

   #3 3rd January 2011, 14:54

   You basically put a small strip in-between the two touching surfaces (eg bearing face and crankshaft) - torque the caps up, and the undo it, the width of the compressed plastiguage will give you the clearance when compared to given widths

   1 user thanked this post: toxic
4. Olly Saxperience Forum Bum Joined: Dec 2008 Meerkat Harborough Posts: 2638 Saxo vtr mk 2

   #4 3rd January 2011, 15:06

   as ross said, its done when there dry/no oil.

   1 user thanked this post: toxic
5. Boyes Regular Poster Joined: Apr 2008 Sheffield Posts: 276 Peugeot 106 GTi, Clio 172

   #5 3rd January 2011, 15:13

   Can also use lead wire and measure using a micrometer how thick it is after
6. toxic Frequent Poster Joined: Mar 2007 Posts: 772

   #6 3rd January 2011, 16:30

   Quote:

   Originally Posted by raunchz You basically put a small strip in-between the two touching surfaces (eg bearing face and crankshaft) - torque the caps up, and the undo it, the width of the compressed plastiguage will give you the clearance when compared to given widths

   so you must get a set clearance and it should be some were in beween that clearance
7. welshpug Saxperience Forum Bum Joined: Jul 2010 South Wales Posts: 3078 ZX 16v, 205 GTI, 309 Goodwood, 405 MI16.

   #7 3rd January 2011, 18:58

   yup, and if it inst (with new bearings) you need a different size bearing if they are available and within tolerance.
   
   or get the crank ground and thicker "oversized" bearings fitted if the above is not possible.