Here's the #1 rod from the previous engine assembly. This is the same rod that had the spun bearing. What kinds of things would cause this? Spun bearing? Detionation? Hydraullicing? (a term my shop used) The motor started the first time and it didn't make any noticable odd noises (at idle) any time. Mufflers were slid-on at idle but were removed when the car was driven (~50 miles).
Yes, all of the above conditions.. But the biggest clue I see there is the heat marks on that rod.. For some reason, at some point in time, that thing was awful hot. On the pin end. Some folks heat the end of the rod to install the press pin, and get away with it, if they are careful with the heat. Sombody may have gotten carried away with that one, and if it were to be dropped when it was glowing hot, that could happen. Or pressed in some manner.. We don't heat the rod here, because you can't properly pre-lube the pin/piston interface, with a hot rod, and cold pin deal.. we machine the interference fit properly, and press them together. I have also had experiences in taking heat meathod installed rod/pistons apart, in which I almost broke my 12 ton press.. the pins tend to seize to the rod. Bad things can happen when you heat and cool metals..to extreme temps. They don't always come back to the same size. So we leave the torch for other uses... Here is a couple of pics, that show the lube on the pin, with this TA Sportsman Rod/SRP piston combo, ready to go into a customer's motor.. This particular motor got press fit rods, which I use up to 600 HP. Above that, we go full float.
I guess my old 350 had some excessive heat buildup too..:af: :af: -Yes it came flying out, with a big KA-BOOM!!!
-Here's another view:gt: -Its bent in TWO directions!!! And by the way, the cam broke into FOUR pieces, and the block got a big hole punched in the side!!??
#1 & #'s 7&8 I haven't been around a lot of B 455s but the ones I've seen damaged; two had 7&8 spun and two had #1 rod out the side of the pan/block. I can see 7&8 spinning account of oil starvation but I've always wondered why # 1 would thro, seeing two in six months made me wonder if this condition was endemic. Don't get me wrong here boys, I love BBBs (have 6) but in 30 yrs of being around engines I've never seen so many bottom end problems in plain passenger cars. (let's not talk about cambearings) ps: Going on vacation to the west coast ( Santa Maria Ca), Spending three days in Phoenix so my wife can see her mother---I think I'll head to Ta Performance (thank God for mothers-in-law).
I've probably seen 2,000+ Buick pins installed, via heat stove, into Buick rods and NOT ONE bent from it. Now, if the rod had a problem to begin with, sure, bending in the upper beam area can occur, but you did check the rods for straight left to right, sideways as well, BEFORE the pins were hung, didn't you. I've seen more pin/rod eye/upper beam failures on pressed in pin stuff than heated pin installs. I've never seen an H-beem rod that had interference style pressed in pins, only bronze bushed pin holes, slide in, with pin locks. In fact, I have tried to get these rods built for pressed pins, and the manufactureres won't build them that way, only floating pins. I would think that the rod shown either had a hydraulicing issue, or was bent from the start, missed by the machinist whom built the piston/rod sets. If there was a valve that had its head come loose, that could do this, but the piston would be real beat up from it. Deflection caused by "hydraulicing is that bending caused by fluids stopping the piston a distance from TDC, solidly. As the crankshaft will still attempt to push the piston past the fluid soild blockage, the weakest part of the chain will deflect, as in the upper part of the rod beam on stock Buick rods. Detonation wouldn't cause the upper part of the rod beam to deflect unless it was so bad, the engine was virtually hammeering itself into oblivion. Would have been really noisy, even over open exhaust. I've heard this in my AA/FA blown/nitro engines at the drags, zoomie exhaust, and another noisy car in the next lane. Spun bearing, don't think so. My Vega with 215 has 200,000+ miles on the engine, 23 years with not even the valve covers off it, stock 215 rods, and it spun a rod bearing, I drove it home with the rod knocking and making a noise you wouldn't believe, 15 miles. NONE of the rods were bent, just the one that sopun the bearing was damaged, on its big end. And, yup, the rod in the pic shows heat from the spun rod bearing, but not enough to cause the beam to bend at the pin end. Sorry, I do think the rod bend was just plain missed by the machinist. THAT could have contributed to the big end bearing spinning. Could also be incorrect heat treating/tempering of the rod as well. We used to re-heat treat stock Honda CB750 single cam rods all the time in the late 70's/early 80's, as they were soft from Honda, and they were all forged rods as well, not Armasteel type.
