Check bearings

[Draco]

Hi Guys

took a motor apart te start rebuilding mine, need your opinion on the state of the bearings, obveously I don't have a clue what will be considered normal ware and what will be considered as damaged. This to me looks quite normal, no "copperish" burn marks and heavey scratches and damage.

The one at the right looks a bit worse

In this pic notice the middle main is upside down.

There is the oppisite side that had to be in the block, amaizingly not much damage or ware??

The bigends looks a bit more worked than the mains I think.

Opinions??

[SonOfAnarchy ZA]

not sure if im correct on this but where its run dry you can see its shiny the bearing should be inconstant in colour i think

[300sx]

those look fine, no problems there at all.. wear looks normal.

remember though that you MIGHT have problems if you intend re-using those, because bearings get crushed when torqued, this is what keeps them from spinning in the housings.. if you retorque those, they MIGHT spin because of insufficiant crush, or wear irregular due to them not crushing exactly the same again..

[Draco]

I am gonna replace, was just wondering because it had a bearing knock but can not really see evidence of that.

Thanks guys.

[SonOfAnarchy ZA]

I dont agree i could be wrong but look at how uneven the wear is and how there is more on one bearing than the other. if everything is torqued to the same spec the wear should be relatively the same.

correct me if im wrong guys.

[Charlvdw]

I dont agree i could be wrong but look at how uneven the wear is and how there is more on one bearing than the other. if everything is torqued to the same spec the wear should be relatively the same.

correct me if im wrong guys.

You are wrong. That's how bearings look after a they've been working for a while. There are a lot of factures at play here , I would have been worried if all of them looked identical.

[SonOfAnarchy ZA]

oh ok kwl would a bearing look like this after 3000km? or does it take a while to get like that?

[300sx]

agree with charl, lots of factors at play.. crank flex, out of balance yada yada yada.. bearing can look like that after 3000km's , judging by the pics there is not a lot of wear..

cannot see one of those bearings knocking.. noise might be coming from somewhere else.. (once again purely judging by the pics)

[Charlvdw]

Even a dodgy torque wrench can cause differences like that. Don't think torque wrenches get calibrated as frequently as they should in any case. Could be a lot of things causing wear like that but no knock I can see from them pics.

[BigKriss]

Crank journals on some of them have taper ground into them hence the "shiny" edge on some of them. As for "crush" , pop the bearing out . If it is difficult to push out, its still good.
If it simply flops out, replace after having bore clearances checked.
Check for cleanliness under the shells.
The rod bearings have slightly smaller clearances but have now worn in.

[harleyzx1400]

Hi. Middle main upside down? No hole for oil = no oil = knock, knock. Not the cause of the problem? Do not re-use bearings if possible. Many years of "ouch" have taught me this. Cheers.

[Draco]

I mentioned the middle main to be upside down but the bearing actually looks good to me, in anycase thanks guys, will rebuild in anyway.