911SC Connecting Rods
 

Can anyone confirm the Part # for connecting rods in an SC engine? The part number on the rods in a rebuilt engine I purchased (which I am subsequently rebuilding after only 8,500 miles) is #930.103.105.0R.

If these are in fact the proper rods for this engine, could someone confirm that there is a lot of play in those rods when connected to the crank? Although the rod journals measure standard, the excessive amount of play worries me.

Any advice on the issue is greatly appreciated,
Duane Duclaux
'79 911SC
duane.duclaux@prodigy.net

Sounds like the rods need reconditioning. A machine shop can shave a little off the mating surface, then redrill the big end so it is round again. No need to buy new.

Duane,

The part number should be 930.103.020.x where x is between 73 and 81 depending on the weight group. Your number is a casting number.

When you talk about excessive play are you refereeing to side play or radial play. The radial play with bearing shells installed and rod bolts torqued should be almost imperceptible. The radial play can be a millimeter.

Ingo

I have a decent set just out of my '79 if you are looking.

Ingo -- thanks for info. You are correct that the radial play (my ability to rotate the rod clockwise or counterclockwise when holding the small end of the connecting rod) is almost imperceptible. The play side-to-side (my ability to slide the rod from one edge of the rod journal to the other end of the rod journal) appears to be slightly greater than one mm, but I assume the rod wouldn't "walk" on the journal when running as long as the wrist pin and small bushing were properly fitted.

If the casting number on the side of the rod is not dispositive that these are in fact the correct rods, where should I look for the part # to ensure that my rods are the right ones and they are equally weighted?

Thanks, Duane
'79 911SC

You should weigh them anyway when balancing the engine. The specs and part numbers are in the Engine Rebuild Book...

-Wayne

Remember that the rods have a lot of room to move back and forth on the crank. THis is the only place the oil has to go. Be sure this isn't what you're feeling when you think you have play. Happened to me my first time, I freaked out, then realized the play was not up and down, but side to side.

But if you still think there is any play up and down, when in doubt, send them out! It's not worth the risk.