Replaced rod bearings and now crank won't turn
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Replaced rod bearings and now crank won't turn
A few weeks ago my 03 cooper S spun a bearing. I have the oil pan off currently and repaired and damage done from the bearing. The bearings are from summit racing and the brand name is kings. I checked and double checked that they where for my motor and resemble the OEM bearings perfectly, although slightly thicker. I assume because they are brand new and the older ones are worn? From here I began to install them, one rod cap at a time, and made sure they faced the right way when reinstalling. The first time I put the bearings in I put them in dry and torqued the rod bolts evenly. The crank turned fine before touching it but would not turn even with a breaker bar on the crank pulley. I took them out and tried again, this time with assembly lube on the inside face of the bearing and again nothing. So I thought to disconnect the rod in which the bearing spun to see if it was just that rod journal holding it up and again nothing. Next I backed all the bolts off a tad so they where not tight to the crank and then the crank turned easily. Any advice on what this could be seizing the crank for ? Or what to do from here ?
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Wrong sized bearings makes the most sense to me, although I can't find any "smaller" or thinner bearings. I'm thinking OEM bearings should be but BMW/MINI isn't clear with the specs.
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What was the King part number??? Should be CR4600XP if the XP series. No XP at the end if standard King bearing. There should be NO number at the end i.e. 025 etc.
You may also have bearings from a standard Cooper...but not sure how you managed to get those on the rods--2mm smaller.
You may also have bearings from a standard Cooper...but not sure how you managed to get those on the rods--2mm smaller.
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dont have the box handy at the moment, but the summit racing part number is: KGB-CR4538CA05 and the kings part number is: CR4538CA05
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OK....so that is the right bearing number (in the none XP series) BUT...the 05 at the end indicates that it is for a crank ground 0.5mm smaller (second undersize).
You need the Summit part#KGB-CR4538CA which is for the stock size journals...since you have not removed the crank and had it turn/machined to a smaller journal size.
NO WONDER IT WONT TURN!!!!!
You need the Summit part#KGB-CR4538CA which is for the stock size journals...since you have not removed the crank and had it turn/machined to a smaller journal size.
NO WONDER IT WONT TURN!!!!!
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Also, just ordered the XP bearings, I'll post how it goes when they get here
Last edited by My.mojo; 09-25-2017 at 08:00 PM.
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I agree with you, although I didn't try to force the crank to turn, as soon as I realized it was tough to turn I realized something wasn't normal and stopped. I knew trying to muscle it would possibly lead to more problems as you mentioned
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You may want to order new rod bolts and have a really good look when you fit the new bearings...plasti gauge may or may not help.
You may have distorted the rod journal or stretched the rod bolts when you torqued them with the thicker bearings...be careful!!
Only removing the rod/piston and using a bore gauge will tell you if you have distorted the journal.
BTW...no offense meant by the "patch job" but it has been know to happen!! People then sell the car on to the next guy.
You may have distorted the rod journal or stretched the rod bolts when you torqued them with the thicker bearings...be careful!!
Only removing the rod/piston and using a bore gauge will tell you if you have distorted the journal.
BTW...no offense meant by the "patch job" but it has been know to happen!! People then sell the car on to the next guy.
Last edited by 1qwkmini; 09-26-2017 at 03:34 AM.