[Gary H]

I recently disassembled a 455 engine that had been installed in a 79' Trans Am by a previous owner. The engine ran great for what it was; 455 with 6X heads, decent camshaft, Holley, etc.. At the urging of the owner, I drove the car pretty hard before pulling the engine since he wanted my opinion on how it ran. It actually ran pretty well. When torn it down I found this with the crankshaft. The number one main had never been drilled from the factory! Keep in mind, this is std/std 9799103 crank, and for all these years it didn't have any direct oil feeding the #2 rod journal. The amazing part is that rod bearing looked ok. The crank mic's standard on all journals including #2. So much for you need X amount of oil pressure per 1000 RPM's. This is a new one for me!

[74SDformula]

Hard for me to wrap my head around this. Can you maybe post a couple of more photos from different angles of the front rod journal.

[johnta1]

Pretty interesting.

Shows how much oil is slung around there.
I take it had no windage tray?

[77 TRASHCAN]

LOL, splash lubrication only on the front of the crank.

I have never thought much of this ancient engineering practice. Now I'm wondering several things about it...

[Baron Von Zeppelin]

Regardless
Don't try this at home.

[turbo69bird]

Wow that is amazing that it ran all that time like that, hard to believe it would survive all these years . Just goes to show you can never say never w how a Pontiac came off the line.
Curious what the date code on the crank and engine block was for this ?

[25stevem]

It's not number one main that was not getting oil, it's number 2 rod from what I can tell.

Number 2 rod must have been only receiving oil to it from what came out of the side clearance of number 1 and oil splash

[dataway]

Makes you wonder ... if side clearance was snug, and oil volume was good ... I bet more oil than you might think would make it to that rod bearing.

Pretty freakin miraculous .... makes me want to have that crank and rod bearing right in front of me to look at.

[PAUL K]

Kinda makes you wonder what good a radius on the oil exit holes does for bearing oiling.

[Gary H]

A few more pictures at different angles. When I Mic the journals there isn't any difference from #2 compared to the other 7. That's pretty incredible to me. I've already sourced a forged crank to take this one's place for the engine rebuild but I'm going to attempt to drill the # 1 main journal and hope to intersect with the rod journal hole.

[sdbob]

I've never noticed that,hmm. I remember drilling a 428 crank according to H-O racing's book. I didnt break a bit when intersecting,dumb luck or skill!

[77 TRASHCAN]

Originally Posted by Gary H

A few more pictures at different angles. When I Mic the journals there isn't any difference from #2 compared to the other 7. That's pretty incredible to me. I've already sourced a forged crank to take this one's place for the engine rebuild but I'm going to attempt to drill the # 1 main journal and hope to intersect with the rod journal hole.

How deep is that forward hole in the front rod journal?

[25stevem]

I would run a wooden skewer down that number two rod oil hole and see how close it comes to busting out on that number 1 main journal.

It may be that the drill bit busted off in there at the factory, or maybe the set up for that drill bit was set up wrong length wise.

Who knows maybe another 1/2” of drilling and you would have the needed hole.

[Mr Anonymous]

Just...wow.

[b-man]

I’ve read about this exact same issue once before, it didn’t affect the service life of the engine.

Clearly there’s enough oil pressure and flow from the neighboring rod that it got enough lubrication for everyday passenger car use.

Says something about the reliability of these old Pontiac V8s.

[Gary H]

Originally Posted by 77 TRASHCAN

How deep is that forward hole in the front rod journal?

I don't remember the exact measurement but running a straw up the hole it appears it's the same depth as the hole is of the adjacent #1 rod journal

[25stevem]

Well if it’s not exiting out on to the number 1 main the it was still not serving it’s purpose.

I recall a post on another site where the guy had a new aftermarket crank and on one journal he found a little what he thought was a crack .

He posted up a few pictures readers where asking for and in the it was a unfinished oil hole .

The guy got a long bit from HF and only had to drill another.025” to get the oil hole finished.

Just goes to show how you can never assume anything when building a motor.

You did a job by catching what you did!

[Jay S]

Pretty amazing it ran so long like with no ill effects and it wasn’t in some 90 year old ladies grocery getter!

Junk as it is. But if the rod feed hole was drilled I would try drilling the main out. I’d do if just for kick’s. Easier with another crank sitting there to judge where to drill.

I took a Pontiac apart once and one of the mains bearings was completely missing. I don’t know what happened for sure. The crank journal mic’s out fine. I think it probably spun and some how didn’t hurt the crank. It had to be driven a long time like that to have no evidence of a bearing in the saddle. Was shocked to see the rod bearings it was feeding didn’t look completely roached! Not pretty, but was obvious someone was driving it like that!

[dataway]

I don't know ... if I came across a magical part like that I'd be inclined to use it as is There is some kind of mojo attached to that crank.