[velardejose]

Hi
This is a ga16 rod metal
It was recently rebuilt with new oem nissan parts, correct tolerances and assembled by skilled persons
It only had 400 km break in kms...
Oil press varied (hot) from 20 psi at idle to 80 psi at 3000 rpm
Suddenly started a clunk noise rpm related, we disasembled it and this is what we found

In all my amateur mechanic years I've never seen something like that
Any ideas?
All other metals came out light worn, and the rod/crankshaft measures correspond to the metals used

 

[velardejose]

Forgot to say, metals and all other parts were bought at Maquinarias, an authorized local Nissan dealer

 

[wes]

What is the OEM spec. for oil pressure on that motor? How did the crankshaft look on that journal surface?

 

[velardejose]

I'll get a couple pics this afternoon

 

[Skoodles]

did you resize the crank befor putting new bearings in? mic the piston connecting rods and the crank and see what numbers you get.

and thats with 212k miles on that part and yours can look just like this with a couple of hundred more miles on it lol

 

[velardejose]

The crank rod journal is perfect, not a scratch on it
The other journals perfect too
Measures are according to the bearings installed
Could it be a bearing material problem?

 

[Skoodles]

The crank rod journal is perfect, not a scratch on it
The other journals perfect too
Measures are according to the bearings installed
Could it be a bearing material problem?

if its just the one bearing there is a posibility that it was just a malfunction on the one metal. in my autoshop book ...wich i dont have right now cause its spring break. it showed pictures of bearngs and wha thappens to them under what conditions and i forgot what it said when it looks like that monday ill let you kno, but you might have found your answer by then

 

[velardejose]

Any help is welcome
Thanks in advance :thumbup:

 

[jer28]

If it was rebuilt then I would have to GUESS that during the cleaning process some debris made its way into one of the oil galley holes and was never cleared out. I think that bearing was starved for oil.
I don't think it is a defect in the bearing itself because of all the wear on the other side of the bearing (where it is not peeled). I'm going to stick with the lack of oil guess.

 

[velardejose]

I thought about that, but the failure should occur at both bearing halfs, and the corresponding half is as new as the rest of them...