Excessive Crankshaft End Play

[jbrown_47]

Hi All,
I can grasp the crankshaft pulley on my 1970 Sedan and move it about .250 inches.  I suspect a spacer or thrust washer was left out at some point. (engine has been rebuilt)
Can anyone tell me what component might have been left out?
Thanks,
John

[feltonminicycle]

There is a spacer between the 2 crank end roller bearings behind the pulley but even if it was left out I doubt you could move it 1/4". The spacer is about 5mm thick. On the primary end of the crankshaft a bolt holds on the front sprocket assy tightly to end of crank and a locating pin locks that roller bearing to the case. Now if that spacer washer was left out you might get some end play but only 1/8" aprox.
Miles

[tgm_enterprizes]

Just can't happen. The rods and pistons will limit any crankshaft end play. Plus, the crank is within .50" of the crankcase.
You have either a lose or missing crankshaft pulley bolt. In my experience, these don't come loose unless someone deliberately turns them counterclockwise. Maybe when doing a timing chain change.
I bet if you take the belt loose or off the pulley, the pulley will come right off. And yes, it would stay on and still turn the fan without the bolt. It has a dogged end that will still make it turn rather than slip. And the belt will tend to make it run in the spot it's supposed to be.
Do you really think an engine with ball bearings will let the crank move that much? Or would even run? If yes, I have some really nice land in the swamps I need to sell, or maybe you would like a nice timeshare in Oklahoma's panhandle. =

[tgm_enterprizes]

Sorry, the crank is within .050" of the crankcase inside. My post inadvertently showed .5 (haha, that's 1/2 inch).
Anyways I stand firm on it's not a loose crank.

[Steve]

I was thinking you were thinking .050" (close to 1.25mm) but there are no ball bearings in the crankshaft, it's all rollers.
I think if the pistons were at bottom of stroke and someone left out all the guide pins & spacers you could get lateral movement. I'm liking your theory on loose crank pulley.
Miles

[dustyspath]

I think the man is talking about the pully  for  the fan  but I maybe wrong

[Bill]

There are pins for each of these crankshaft bearings, movement could be there if these pins were not in place.
Otherwise any side movement would be normal.

[John Brown]

Thanks for all the input.  I knew the crankshaft was the roller bearing type.  Most of my experience has been with roller bearing crankshafts in old Harley-Davidson's; in these, the crankshaft end play is set by varying the thrust washer thickness. On my Honda engine, I thought I saw in-and-out movement of the pulley while the engine was running. I gently pried the pulley outward and then pushed it back in to determine the total end play.  The amount concerned me.
I will check the pulley and bolt to determine if they are the source of this fault.
John