Low oil pressure diagnosed, question on main bearings - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• Low oil pressure diagnosed, question on main bearings by vwnut84 on 20 Oct, 2008 09:58
• Ok, so after getting my running issues cleared out (turns out I had some dirt in an injector...) I finished with the install of the brakes and oil pump from a low oil pressure issue. So after the oil pump install I still have low oil pressure, not enough to trigger the light yet, but it's just below two bar at 2k rpms and at about 3k rpms I think I hear an engine knock of sorts  At idle after the oil is at temp it will be as low as 10PSI in the head. So at this point I'm looking at putting in main bearings to try and slove this.
  
  My question is, can you do these in the car by "walking" them in? I had heard of this working on a regular gas VW 4cyl but not on a diesel.
  
  Also, do I get stock bearings? or the next oversize? Is this going to be a temp fix and I should be looking for a shortblock?
  
  Oh might help to know the car.... :p   it's an '86 Turbo diesel Jetta with 208k on it.
  
  Thanks a bunch guys!
• #1 by zukgod1 on 20 Oct, 2008 10:07
• Contact this guy for bearings.
  
  http://vwdiesel.net/phpBB/profile.php?mode=viewprofile&u=798
  
  
  Yes you can walk them in with the crank in place.
  
  It's kinda hard to get the end ones due to the bearing caps being so close to the alum plates that hold the main seals.
  
  Be sure to do your rods while your there.
• #2 by vwnut84 on 20 Oct, 2008 12:21
• Awesome! Thanks for the info.    Gonna order them up (with rod bearings as well) and get this diesel well again.
• #3 by autoholic on 20 Oct, 2008 12:38
• You should also inspect the front of intermediate shaft for fractured outer ring and check bearings. I have seen people replace rods/mains but the actual problem was the intermediate shaft. Out of 4 engines I had, only one of the int shafts were good! These are worth looking at anytime doing major engine work.
• #4 by zukgod1 on 20 Oct, 2008 12:50
• Quote from: "autoholic"

  You should also inspect the front of intermediate shaft for fractured outer ring and check bearings. I have seen people replace rods/mains but the actual problem was the intermediate shaft. Out of 4 engines I had, only one of the int shafts were good! These are worth looking at anytime doing major engine work.

  
  
  This is a good point.
  
  Maybe you should do a couple random rod/ main bearings with Plastigauge to verify they are worn. If the gauge out correctly the problem could be the IM shaft bearings.
• #5 by autoholic on 20 Oct, 2008 13:00
• Probably would also look at the cam saddles, those things can wear hard, and the caps are easy to check if you have not already.