Con-rod good for use?

[Wentzel]

I found these marks on a con-rod and lapped it a little with sand paper on a mirror. The remaining marks is clearly visible and can be felt running a finger over it. Will this be a problem or should I not worry about it?

Thanks

[Cyndi Kritzinger]

THIS LOOKS LIKE IT COULD BE "THE LAST STAND AT THE HIGH CHAPERELLE" BETWEEN DAWIE AND TONY.

[Terry Phillips]

Believe it or not those marks will help by the small pit marks holding more oil than a good one does, but there are wear limits.It is the same as a pitted gear it will hold more oil on the pitted tooth than a good one. So for me that conrod is ok to use. my 2c worth

[Wentzel]

Believe it or not those marks will help by the small pit marks holding more oil than a good one does, but there are wear limits.It is the same as a pitted gear it will hold more oil on the pitted tooth than a good one. So for me that conrod is ok to use. my 2c worth

Thanks Terry

I was thinking the same thing but wanted to make sure. I do know of the side clearances and will check it also.

[Tony Z]

Yes, the pitting might help to hold more oil, but the function of the sides of the con rod is to reduce oil flow out of the bearing, thus aiding in increasing overall oil pressure in the bearing itself. If the oil flows out too easily it is possible for the oil wedge to collapse or at least be reduced. Conversely, if the oil cant flow out easily enough then you overheat the bearing by not having enough oil flow.
The oil pump pressure gets the oil to the bearings and into the bearings, but the wedge is made up by the relative velocity between the crank pin and rod bearing and its this wedge that carries the load.
In a stock engine, it might still be ok to run those rods, but I dont really want to be the one to say that and then you end up with issues.

[retrovan]

The best advice I can give is simple...

Do not mix new and old parts in an engine build.

As said, the oil flow is important, and the old parts will allow more oil to bypass, which in it self is OK if you using a thicker oil, and the engine will run sweet.

BUT

If you have old and new mixed, you will have too much oil flow on old parts, which is good, but low oil flow around new pasts which is bad, and will weld up and kill motor.

If only new parts the oil flow is again uniform and working well.

I have seen a lot of engines rebuilt using only old parts, and they run sweet.

So with all this info, you need to work out what you want to use.

Herman

[Wentzel]

That makes sense I think. If the side clearances is within spec or allow for more space I could lap it some more and try to remove the rough bits.

The whole engine is in the process of getting rebuild so all the bearing and bits will be done. Also a lot of new parts.

Thank you Tony & Herman