All,

I've just reassembled the pony for my D2 and when I put the flywheel on, noticed excessive end play. I had a machine shop to sleeve the cylinders and bore it to standard, as well as had the crankshaft welded up and ground to standard. New dowels were installed and I assumed everything would be correct. I mounted the pony without the flywheel to allow easier clearance behind the hydraulic lines. I haven't yet torqued it down, but i did snug it with a quick hit with the impact wrench. I noticed end play way more than I expected. i measured with a caliper and shows about .1". I have attached the caliper dial showing the amount of play, as well as before and after photos of the flange end of the crankshaft. What could be causing the excessive end play?

It is possible that whoever ground the crank took some off both sides of the thrust surfaces. If this case you will have to drive the bearing in further to take up the excessive end play. This will require removing the locating dowel out and relocating the hole in further. This will probably require getting a new bearing. Keep to the original cat specs on end play. These motors have a bad habit of vibrating the dowel out and shifting the bearing out resulting in excessive end play. This will end up allowing the crank to strike the block inside the crankcase, possibly cracking the crank or other damage. I have a D4 with the same disease but have not getting around to fixing it. I was thinking about installing the crank, drilling and tapping the hole for a allen head set screw and locating it in place. Don't forget to drill a hole in the screw for oil for bearing lube. It may also pay to loctite the bearing also. If you ever have to change the bearing, just put a little on the end casting and you can press the bearing out. Hope this helps you out. Cheers, Larry. P.S., Don't use too long a set screw that will contact the bearing surface on the crank.

"Larry" wrote:

It is possible that whoever ground the crank took some off both sides of the thrust surfaces. If this case you will have to drive the bearing in further to take up the excessive end play. This will require removing the locating dowel out and relocating the hole in further. This will probably require getting a new bearing. Keep to the original cat specs on end play. These motors have a bad habit of vibrating the dowel out and shifting the bearing out resulting in excessive end play. This will end up allowing the crank to strike the block inside the crankcase, possibly cracking the crank or other damage. I have a D4 with the same disease but have not getting around to fixing it. I was thinking about installing the crank, drilling and tapping the hole for a allen head set screw and locating it in place. Don't forget to drill a hole in the screw for oil for bearing lube. It may also pay to loctite the bearing also. If you ever have to change the bearing, just put a little on the end casting and you can press the bearing out. Hope this helps you out. Cheers, Larry. P.S., Don't use too long a set screw that will contact the bearing surface on the crank.

Well it did for me thanks. I knew I had to go back in because I had 0.00 end play. When I go back in I'll be loaded for bear this time:hail:.

Hi Team,
you need to be aware that the end play is set by the length of the front main bearing--the one on opposite side of the crank to the flywheel or rear main bearing-- and not on each side face of the crank mains.
The play/thrust is taken by the side face of the crank and the oil slinger plate behind the drive gear so no thrust is imparted to the centre web of the crank which is a weak spot hence the care needed when fitting and removing the flywheel and the tight fitting double key, one way only fitting of the drive gear--note :- the C timing marks must align for correct valve timing--as well as when tensioning the flywheel nut.

The main bearing in question comes from the factory longer than needed and you must measure the main journal length between the crank side face and the crank shoulder, where the drive gear butts up to, to work out how much to remove from the bearing for correct end play.
Positioning of said bearing by the dowel hole ensures the crank is correctly positioned in the block.

It is not straight forward as odd ideas were used to save stressing that centre crank web on these engines--there are a lot of traps for the unitiated as I found out when doing my first one as a Dealer Apprentice back in the mid 1960's.
Lots has been written on here with pix about this subject over the years.
SEARCH may or may not find some of them.
Cheers,
Eddie B.

Like EDB said, the end clearance is controlled by the length of the bearing vs the assembled stack of crank, bearing, slinger, & crank gear. The easiest way to try out is to make a dummy spacer to take the place of the crank gear, only with a slip fit so you don't have to fight the gear off & on getting it right. Put the bearing & dowel in with loctite, and ream the dowel hole in a drill press following the book instructions. Last, don't beat on the flywheel/crank shaft with anything, use the proper wrench, puller & the bearing will stay put.

Thanks for everyone's responses. Looks like I'll be pulling it back out and tearing it back down. Got too much $$ invested to take a chance.

Neil - I agree. At least it will be clean when I disassemble it this time. I just need to figure out how to fix it when I get it apart. Right now I'm having a hard time visualizing what the problem is, but I'll probably figure it out once I get everything apart.