Sooooo, I found out that the #6 rod bearing spun in the silver car's 455(468) due to an over rev situation (like 7200). I did this around 2014 and it has sat ever since. The only reason I knew it spun a bearing is it seized (wouldn't turn by the starter) a while after that over rev. I had hoped that it wasn't a main bearing and I was right.

The question is how do I approach the repair? I know I will pull the crank and that rod (and #5 also) to have the crank machined at least 0.010" under for #5/#6. Should I only have those two rods and crank reconditioned? Or should take the whole thing apart and have everything checked? And if I do that, should have them all undersized? I am planning on sending it out in the next week or two...
Thanks all...

 

It’s going to have to come completely apart for cleaning. There will be debris all thru the oil passages.

The machine shop will be able to tell you what needs to be done to the crank and rods.

 

At 7200 rpm, you may have floated the valves, and tagged pistons with them as well. You also may have broken valvesprings or dampers and possibly ran the bottom of the retainers into the top of the valve guides, so look for cracks on those as well.

As Matt69Olds said, you will have to completely disassemble the entire engine and have the crank turned by a very good shop if you don't want more problems than what you have now. Believe me, after what I have seen multiple times from very "reputable" shops, You will need to ask who you can trust in your area for excellent crank turning work and block inspection. Vortecpro saved our butt on our build after getting messed over by other shops and machinists.


I would have the crank, block, and heads magnafluxed as well to make sure all is good before you do any new work on these parts.

Good luck and keep us posted.

 

I missed the part about 7200 rpm!!! Before spending a dime on anything else, I’d invest in a rev limiter!!!

 

Rev limiter was sitting on a shelf waiting to be installed. Crap! Valves wouldn't have floated. Non stock valvetrain. I guess I am taking it all the way down as y'all are right. It needs to be completely cleaned.

 

Not sure about the cast or nodular cranks but with a forged crank a spun rod bearing usually tweaks the mains such that they require regrind as well. Definitely have the big ends checked on ALL rods. Yes, there will no doubt be FOD throughout the oiling system and possible metal in the skirts of the pistons. Full tear down and clean and inspect required.

 

I haven't heard that term since i left the service.
Had to do "FOD" duty on the flight line almost everyday during my service tour.
That is unusual, but cool.

Gene

 

Some quick pics

 

definitely FUBAR.... sorry about that for you man. Just hook on to a great machinist to inspect everything with a very close eye, or better yet.... start over with a new virgin block and all new parts.. You can reuse some things like your cam and setup/rockers, ARP fasteners, etc.

 

Dang, sorry to see it, Joe. In addition to what's been said, checking the rods will be critical. You likely have some heavier pistons in there, and the high RPM puts tension stress on the rod bolts and pulls the parting line in towards the journal. Just because one spun, the others were likely stressed pretty hard too. If you're keeping those rods, a competent shop needs to check all the rod bores carefully and potentially resize.

 

So, maybe new crank, rods and all new bearings would be the best way to go? Keep everything else? Don't see why the block would need replacing, but I'll pull all the rod and main caps and inspect everything.

Could be a bunch of decent parts for sale soon...

 

If you're gonna beat on it, I'd prefer aftermarket rods... that's just my preference. The cheap way is to get the crank cut, the rods resized (I've had it done without taking off the pistons because they were pressed pin), clean the hell out of everything, and put it back together with new bearings, checking everything. From there, everything gets more costly.

What pistons do you have? The downside is since you're already 0.060" over, re-honing could put you into customs (or require skirt coating to take up clearance), unless you have a tight bore clearance now and you move up to a piston that expands more and needs the clearance (2618 alloy).