Why am I destroying rod bearings?

[RRoller123]

I have a 2L Block, fitted with pistons, Crank, Rods, etc., that I bought as a complete engine as a source for spares. I have used everything off of it that I probably ever will, as I just had a separate short block done with 9.8 pistons. I am located near the Cape Cod Canal. This block came from a very good running car with fine compression (in the 140's), and it spins freely. It was oiled up when I took it, quite a few years ago, and is still fine. I suppose $100 bucks would take it? I should just get it out of the way in the shop. Depends where you are, if it makes sense.

Pete

[axelbaker]

I have a 2L Block, fitted with pistons, Crank, Rods, etc., that I bought as a complete engine as a source for spares. I have used everything off of it that I probably ever will, as I just had a separate short block done with 9.8 pistons. I am located near the Cape Cod Canal. This block came from a very good running car with fine compression (in the 140's), and it spins freely. It was oiled up when I took it, quite a few years ago, and is still fine. I suppose $100 bucks would take it? I should just get it out of the way in the shop. Depends where you are, if it makes sense.

Pete

Thank you for the offer, I got one locally.

[InnocentGuns]

Very curious to see how this last rebuild went.

[brad131a4]

I'm going by what I've read and if I understand correctly. You are trying to break- in the motor using synthetic oil. If this is correct then you will just keep destroying them. Synthetic unless formulated for breaking in a motor will never work. Also just about all the new oils and synthetics are missing key ingredients for breaking in a motor. Viscosity isn't much the issues as what's in the oil for the bearings and rings. Get specific break in oil and use it as instructed. It has to have ztpp or what ever they call it. Stop being cheap on that and the rest should be easy.

[Nut124]

Bearings do not need break-in, they need lubrication, oil pressure.

The stuff you may be referring to is for cam break-in. Even that is not much of an issue in Fiats. More so in US flat tappet V8 cams.

The Fiat bottom end is extremely reliable. Anyone who destroys bearing there is doing something wrong and it is not the oil.

[brad131a4]

Ok Nut124 I can see that in some form. I've only had problems from oil starvation in the motors I've had to tear apart. One which turned out to be my fault for not catching a leaky gasket before it caused the issue. That being said I only replaced the bearings to the crank and rods and cleaned out the motor as best I could. Did I mention this was done with the motor in the car still. Not something I ever want to do again. I was young and had to be back to school that monday. This was done on a saturday and sunday. In the street in front of my parents house. No hot tanks only cleaning I could do with wd40 and what ever other cleaner I could use. Plastigage the bearings and even had to drill the oiling holes in different locations as I couldn't get the correct ones for the crank. But I still used break in oil and changed it twice. I then headed out for a 300 mile trip across Washington state back to college. 4 years later and 80,000 miles I sold the car and never had a issue with the motor or bearings. So how can it be something that axle is doing wrong if he is following the correct way to rebuild the motor. Where I was flying by the seat of my pants and it was fine? Lucky I guess? This also was after I'd driven over 200 miles on my way home with the motor knocking and my figuring out I was hosed but had no choice. I will say that I was surprised as hell that the crank din't even have a scratch on the bearing surfaces even with the bearings being toast. It was impressive that was for sure.