Interesting find on STOCK CON ROD after teardown....engine gurus please

[PaulRV6]

I'm the one that posted about low oil pressure after newly rebuilt engine. Decided to teardown only to find cam brgs and mains wiped.
One thing I noticed about the rods (which those brgs looked ok except for some grooves from debris) was that the brg tang groove is split apart at the splitline and is opened up to the start of the threads, 4 of the 6 rods are like this. I do not remember if I would have installed them this way but it sure looks odd.

I looked at a set of 4.1L rods and 1 out of the 6 was like that, but they all seem to be thin on the backside of this groove.

Can you guys with engines apart check out your rods and let me know if this is common, or it is a problem. I wish I had a digital cam to show a pic but words will have to do. Let me know if you need more explanation. I am concerned!!

paul

 

[PaulRV6]

Just to add, the brg fit (OD to the rod bore) was good with no looseness within the bore. The big end was resized and honed with new SPS bolts.
Thanks much.

paul

 

[PaulRV6]

Geez, I am the only one posting to this, one way to keep it going.

Any engine builders out there that can comment on my con rod concern? If not, who can I call to ask the question? Please let me know.

paul

 

[Carolinaturbot6]

Paul, I would like to help, but I wouldn't want to steer you wrong buddy. I'd contact either:
Nick Micale
3334 W. Marconi Ave
Phoenix, AZ 85053
602-866-9908

OR: Dave Weber
32325 Cook Road
North Ridgeville, Ohio 44039
440-327-7702

They should be able to help you. Good luck.

 

[tc86gn]

Hey Paul,
I am a little new to these engines, but for what its worth, I looked at my stock rods that recently came back from being reconditioned. They all have the bearing tang groove that you describe.
All 6 of mine actually go to the edge of the rod bolt hole. I would have to say this is normal,or at least acceptable. the machine shop that did mine would not give me back a set of rods that were not good.

Tom

 

[PaulRV6]

Thanks guys.

Tom, on your rods does the tang groove break into the bolt hole at the horizontal split? Mine are all split at the top.

paul

 

[tc86gn]

4 out of my 6 are that way. looks like the way it was made. doesn't look to me like any kind of crack.IMO.
Some of the more experienced guys may be able to add some info here.

 

[Buick Mark]

That is normal for the cap screw rods, even the 350 motors from 73 on up are the same way, no need to worry. As long as the bearing has a light press fit when you install the halves, your good to go. Mark