Re: Steel rod life expectancy
 

That break was caused by the spun bearing.

Re: Steel rod life expectancy
 

Well , in the end , I blame myself for be stupid enough to A) continue to run it when I KNEW the rods had been in there for a while and B ) being too lazy to tear it down over the winter where I may have seen a problem.....but , like I said I'm a slow learner:mad:

Re: Steel rod life expectancy
 

Bearings don't usually fail by themselves. The connecting rod dimensions change or oil supply changes.

Re: Steel rod life expectancy
 

Or clearances were wrong to begin with.

Re: Steel rod life expectancy
 

Not in this case. I'm a machinist for a major airline for 26 years.........and years prior to that. I have and have access to , every conceivable bore gauge and mic's anyone would need.
I assemble and check them........no chance in hell they were wrong.
Generally .0025-.003 at the vertical. Or whatever the rod manufacturer suggests.
I just ran it too long without an exam or freshening.

Re: Steel rod life expectancy
 

I suspect this was the case.............:confused:

Re: Steel rod life expectancy
 

SBC? Why so much clearance? You do know that aluminium rod will expand much faster than the steel crank, right? Imagine how loose they are at operating temps. I don't run my steel rods that loose.

Re: Steel rod life expectancy
 

Mine was instigated by detonation

Re: Steel rod life expectancy
 

Well , I don't know what to tell ya........engine builders a lot smarter than me have run em that way for years........if I ran em tighter and it failed I'd be blaming it on that.........

Re: Steel rod life expectancy
 

Yep. Hammering the bearings causes the ends to pull in & squeegee oil off the crank. Too much clearance often has the same effect, just takes longer.