Need an Undersize Rod Bearing I screwed up a friends 2003 Mini Cooper S 6-speed. I replaced the clutch and fired the engine up while the front end was still up on jack stands. Apparently it was at too steep an angle so I starved the engine of oil and spun a rod bearing. SON OF A _____! Not knowing enough about what I was doing I sanded down the journal from under the car. Not being aware how close the bearing tolerances had to be, I took the journal down to where all the scratches were gone. I put a new bearing in and the car ran fine until I got on it. Then the bearing spun again apparently because I had taken WAY too much off the journal. So now the low spot is .022 undersize. The only undersize bearing I have found is from BMW and it is .010 thousandths or .025mm undersize. I have found a company that sells bearing shims that will make up another .010 which still leaves me .002 short of where I need to be. And, the journal is not yet round. The high spot is .018 higher! Ughh. So I have some work to do to get the entire journal down to 1.790 thousandths from 1.812 without taking any more material off the low spot. I could run a second shim, (they are available from my supplier in 1,2 3,4 and 5 thousandths) but I'm afraid they might not lock in the bore and spin? What I REALLY need is a bearing that is more undersize than .025. Does anyone know where I can find one? I have spent hours on the internet looking with no success. Any help would be much appreciated. I do NOT want to pull the engine to fix this. I AM going to do it my way whether it works or not, so please no "it can't be done or it is stupid comments." I know this is not the correct way to do the job but it is the way I'm going to do it. If it doesn't work, I'll cross that bridge when I get to it. I hate F___ING UP! Thanks for reading this! By the way, Mr. Bean provided the following info that appears to indicate the journal can go .027 undersize. I just need the bearing to do it.

The rod journals on the crankshaft are 45.992-46.008mm

6. 0.023-0.067mm new; 0.070mm wear limit

7. 0.022-0.062mm new; 0.070 wear limit <-- full disclosure, my repair manual says 0.700mm wear limit but I believe this is a typo and should be the same as the rod clearance limit.

 

Save yourself time and future problems, take the crank out and get it professionally done, or by a new/ used one. Tolerances are tight for a reason.

Good luck.

 

+1
From the man who rebuilt one.
If you ran dry and spun a bearing on the bottom....i would look at the top end ...the far end of the cam is trashed first with low oil psi situations.... (guessing the pickup was also dry?) You might jump through hoops to fix the bottom...and have the far end if the cam fail next...
Not saying you are screwed...but I'd check the top BEFORE you jump through hoops to make a fix work on the bottom. It certainly sounds like you know your way around a motor .
Good luck...crappy situation to get into.

 

you cant sand those by hand, they have to be turned down in a machine. I would pull engine and replace crank if it were me

I've repaired oil starved engines before, although not a mini what zippyNH said is right, I have found the top end goes oil starved first and it trashes cam cams, in fact typically I only have to repair the head/cams