I have a 17.5 hp briggs and stratton riding lawnmower engine.. The other day I was mowing and it started making weird noised and shut off.. After tearing it down i found that it had busted the piston rod.. My question is this: would just replacing the connecting rod fix this or is there something else I should be
looking for too?

Everything else seems to be ok except for the crank is scracthed a little bit where the piston connected to it.. Can this be cleaned with an emery cloth or would it have to be replaced too??

any help would be greatly appreciated, thanks

To fix it right,you could order in an undersized con rod,and take the crank to a good machine shop and have it turned to the correct spec.I had a customer that threw a rod on his 11hp B&S,and he couldn't afford to fix it right,so I cleaned up the crank with wet sandpaper,going from like 180 to 800 grit,and reass with a new rod.It would come in for other things over the years but never failed at the rod.I was always curious whenever I saw it get dropped off how it was.

I guess it depends on if you have the proper clearance there to begin with.It's common for the block to get cracked on the side,or the liner at the bottom,or cam damage when it goes,so be sure to really check those areas out good before ordering parts,or a short block may be the best route.In most cases,a rod gets thrown from lack of oil that causes the scoring,seizing.It's important to verify that you don't have an excessive oil consumption problem,like from top end wear,or it's just going to possably reoccur.

Take care,
Steve

If you want to do it on the cheap, then yes you can just polish the crank with some emery tape and install a new rod . I have done this many times and have had good results, but there is always the chance that the repair may not last. As ossaguy stated, if you want to do it right, then an under size rod and a trip to the machine shop or a new standard rod and crank would be needed. If you decide that this is the way you want to go, then you also need to check the upper and lower bearings and make sure they are within specs.

Best of Luck...

thanks for the info... am i right in assuming that the piston has bearings that go between the crank and piston rod?