Change "big end" bearings?

[GodSpeed]

If they look like this should they be changed? No rough surfaces just the outer edge of the bearing thats slightly polished.

Are these even called the "big end" ones or are these "main bearings"?

 

[Donny_Dog]

who's is that porsche?!

 

[SkidMarx]

For the sake of £50 id change them. Would be a good idea to see why they've gone like that tho?? Never seen them do that on one side.

 

[sideways danny]

That is a main bearing not a big end. I would change it simply because it's apart

 

[GodSpeed]

That is a main bearing not a big end. I would change it simply because it's apart

So this is normal wear nothing strange?

I guess its best to change both big ends and mains then. Where can I buy Original Renault ones at a good price?

 

[Pete@Auto-Nation]

No point putting them back in now it's all stripped. Check the journal to bearing clearance with plastigage to make sure there is no ovality on the crank, which could cause those marks IMO. Even better, check the journals with a micrometer too.

 

[red21]

As every body is saying I would change the bearings as they are already out, but to give you an insight of bearing failures follow the link.
http://www.engineparts.com/publications/CL77-3-402.pdf

 

[GodSpeed]

As every body is saying I would change the bearings as they are already out, but to give you an insight of bearing failures follow the link.
http://www.engineparts.com/publications/CL77-3-402.pdf

Yes I just read that... If I interpret that right the crank may be bent? Seems very unlikley for an engine that have been so good taken care of. But what do I know. :dapprove:

 

[Fred@BTM]

that look like the main behind the flywheel? nothing too out of the ordinary for (i would estimate) 60,000 km?

 

[GodSpeed]

that look like the main behind the flywheel? nothing too out of the ordinary for (i would estimate) 60,000 km?

Yes thats the main behind the flywheel, and the engine have done almost exactly 60000km many of these on track. With oil changes every 5000km and propper oilcooling.

I guess its best to change them even if its not out of the ordinary?

 

[jack_kemp]

<3 Fred. You're a genius.

 

[Pedro]

Were there be a god, his name would be Fred.

 

[Tom84]

if that was me id stick it back in as long as there is no heat cracking

 

[Fred@BTM]

christ i've impressed even myself with that one! LOL

 

[GodSpeed]

christ i've impressed even myself with that one! LOL

So you vote for a change?

If so do I need to follow the AWT F4R rebuild description or is it overkill?

 

[franx]

AWT , overkill

 

[GodSpeed]

Took the crank out yesterday and the wear was the same on all crankshaft bearings. Even wear on the top halfs of the bearing and all the lower halfs have more wear towards the flywheel side (like the picture). Noticed that lateral play was way out of tolerance. From what I have read it should be 0,07-0,23mm and it was more than 1mm on my crank. Could this have caused the strange wear?

 

[Fred@BTM]

yes, sounds like you thrust bearing is shot, luckily you can get oversized thrust washers/bearings

are you running a monster clutch or anything?

 

[Budgie]

I've got a straight crank and bearings if it's any use.

 

[GodSpeed]

yes, sounds like you thrust bearing is shot, luckily you can get oversized thrust washers/bearings

are you running a monster clutch or anything?

Do I need oversized thrust washers? Or do you meen the crank may have worn along with the washers?

Im running a Helix paddle clutch, dont know if that is a monster? Only been running it for 8000km.

Budgie thanks, but it seems the crank is ok only the bearings seems to be worn. Will measure it up later in the week.