18 replies to this topic

[Big_Adam]

Evening,

Ok this should be my last bearing based post (after all the cam bearing stuff) this time it's the con rod bearings. One of them looks a little on the scuffed side just wanted to know if its still good.

[attachment=34195:P1010199.JPG]

and now

Random Link ... ... of doom!

Edited by Big_Adam, 05 June 2007 - 02:15 PM.

[Road Runner]

They are called Big ends and the others are main bearings.

[Big_Adam]

Ok, cheers RR.

So are my big end bearings knacked?

[mini-majic]

they still look like they have got life left in them too me. but if you wish for peace of mind it is always good to change them.

Edited by mini-majic, 05 June 2007 - 05:56 PM.

[danwebster]

It could be the light reflecting off them but they don't look too clever to me, they should come out pretty close to how they looked when they went in.

Worth changing for what they cost.

[Big_Adam]

Few more pics. Thinks the previous owner ragged the engine a bit too soon.

[[email protected]]

They are knackered. If they haven't already started scoring the crank they soon will!

[MiniMonsta]

I agree with simon, a scored crank isn't good. If you are not sure if the bearings are worn by visually giving them a once over you can allways quickly bolt them back onto the crankshaft and try and move the conrod up and down to see if there is any "play" if there is then you have worn shell bearings or big ends. I never make complete sence so here is some ms paint skills.

[Turbo Nick]

they're f**ked and i'd say your crank won't look too clever either. run your nail over the crank and feel the ridges in it.

[Big_Adam]

Can't feel any ridges but I can see the surface has been scuffed as there is still a shiney line in the middle were the oil feed is.

Right, so the crank (pardon my french) and the engine build (french, pardon, please) new plan!

Sod the new engine insted use the cam, oil pump, and flywheel on my current 998. Leave the new engine till later in life.

[OllyD]

Aren't these kinds of things fairly par for the course in an engine rebuild? Otherwise it would just be called an engine take-apart-and-put-back-together-again.

[Big_Adam]

Not when you bought the engine thinking they were only 2000 miles old and still good for another 48,000 only to find their not in good condition they are in fact along with the crank.

Yes, they for a normal rebuild regrind the lot. I didn't budget for that as I thought they would be fine.

See how mightly wrong I am.

Edited by Big_Adam, 05 June 2007 - 10:36 PM.

[Big_Adam]

Le Bump!

Right, found out why the bearings were screwed. Harden crank with regular bearings.

So what stock size bearings do I need for a harden crank?

[Sam]

never heard of that before, they are like that because of a lack of oil

[Ethel]

I'd take the crank along to a machine shop let them check it out and regrind if necessary - they'll be able to size the journals so you get the right shells at the very least.

Shouldn't cost you any more than the gaskets to rip it to bits in the future if you just bolted it back together as it is now.