Rb25 Engine Bearings

[lachlanmatthew]

can somone please help me, i posted a few days ago but no one seemed to know anything as there was no reply!

i have taken the bottome end of my motor apart with the head still intact on a engine stand with the intention of replacing the big end bearings and main bearings and thrust washer and the oil pump also. everything is appart. bearings have worn a little but i guess you would expet that with 100,000 kms and a heavy foot for a least 40,000

there a no deep scores in the bearings just slight wear (coulor) and the crank looks perfect, it will be getting crack tested and the journals looked at to be positive that its fine.

my problem is that when i spoke to nissan and tried to order bearings the told me when ordering standard bearings i need to cheak markings on the crank and main and con rod caps and compare this to a chart and work out the grade i need for each bearing. they faxed me a graph but its in japanese and i cant make any sense of it.

PLEASE SOMEONE HELP ME!!!!!!!

[LTHLRB]

just get yourself a set of ACL bearings..

What do they mean by grade on each cap? caps should be the same but numbering should be different and so on.

[lachlanmatthew]

when you buy the acl bearings.... standard size not oversize i think its the same as nissan, they grade the bearings depending on the markings... think it may have somthing to do with balance or the exact circumference of the journal.. i dunno, all i know is when you buy a standard bearing you need to know if its a garde 1,2 or 3??

[LTHLRB]

wudnt have a clue with that one bud.

[lachlanmatthew]

wel nissan have told me i need a grade of bearing, those markings on the front end of the crank on the conrod caps, on the side of the con rod, on your main caps.... they are there apparently for bearing grades. i know if i get the crank machined to 10thou oversize i can just order a set of 10 thou oversize bearings... but there is nothing at all wrong with my crank. anyone else have any idea?

[$weetDreamZ]

Is it possible for you to take the necessary parts to your Nissan dealer to get them to assist you with picking the right grade? That might be easier than just taking a punt.

[lachlanmatthew]

yeah i spoke to the head mechanic of marooka nissan service and he suggested that because he couldnt tell me over the phone... said he would have to look at it. it just seems like such a pain in the arse to get it there... its all in parts... the head is still on the block... its upside down on a engine stand. plus i have to get time off work to make it there!!!

i really thought i could just pull it apart and replace the bearings like any other motor.... this SUCKS!!!!!

[Craved]

Find a trusted engine machinist to lynish the crank, then find bearings to suit.

i did this recently with my RB30 and came back with King bearings and lyncished crank for $300

[lachlanmatthew]

king bearings and linised crank for $300? so who did it and did you just send them a crank and they linish it and give you bearings that will fit?

[Craved]

king bearings and linised crank for $300? so who did it and did you just send them a crank and they linish it and give you bearings that will fit?

Nepean Engines in Penrith.

took the crank to them, 2 days later got it back with new bearings and lynished . i think though that the mains are another brand not king come to mention it, as he said that the main force is on teh big ends not the main bearings, this is for a 300rwkw power goal which he knew about.