Fitting crankshaft

[jddevel]

What is the recommended or easiest way to fit a reground crankshaft in a XPAG. I`ve reduced the centre bearing to 003 thou to give end play but am finding it currently difficult to get the shaft to turn even at 20lbs torque, I`ve "set" the caps with a rubber hammer. What am I doing wrong?

[Tom Lange, MGT Repair]

Chances are you have turned a cap so the bore is no longer true. Obviously the rear can only go one way, so check the witness marks on the other two to show which way the caps should go.

Tom Lange
MGT Repair

[Steve Simmons]

Have you checked bearing clearance? Maybe try tightening one at a time to see if only one binds. Plus making sure they are on the right way as Tom notes.

[i.thomson]

I assume it is torqued up. You should not need to "set " the caps. They may appear to be slightly proud when first fitted but this just gives a slight "pinch" as they find their own set when tightened. loosen off the caps and see how easily it turns. If still tight take the shells out, clean and lubricate them thoroughly (i'm sure they are already) and check the small "tag" is correctly oriented in it's "relief" in the caps. Then tighten them one at a time to find out which one is binding. Double check the thrust faces. I find that tighter can often be better at the thrust faces as they are difficult to get right and soon loosen (wear) with turning. In the final case recheck the grind matches the shell size. Good luck and don't panic.

Ian

[jddevel]

Thanks for the comments. The old problem of having a problem but then continuing to do the same thing over and over again!!!. Solved in two ways. First when reducing the width of the centre thrust bearing it was still pinching when torqued down PLUS although I`d marked the caps (no original marks seen) using a punch, for some reason although all other caps including bigends had been stamped on the rear of the cap to provide orientation for some reason I`d marked the front main bearing cap on the front top edge. Result I`d reversed it`s fitting. Only realized when I studied all my photos and saw the mistake, Refitted the cap and now all turns-well hopefully will continue to do so once I`ve refitted following piston installation!!!

[i.thomson]

Well Tom got it. We've all done it though often the cap will not fit cleanly over the studs when the wrong way round to give us a clue. Now to repeat the excercise with the rods. I have in the past checked and double checked their orientation and still got it wrong due to working with the block upside down on the bench...or maybe it's just incompetence on my part.

Ian