willysmjeeps.com

I'm been having issues with rough running for some years now after engine warms (worse on higher temperature days) and heavily relying on past forums to try and problem solve. Next on my list was crank case and vaccum system.

1. Checked my crank case valve and noted the ballcheck (bearing) is rattling inside after shaking it. Is this normal??

2. I removed the fording assembly some years ago (due to non use) and connected the valve direct into the engine port. It is still tubed to the side cover manifold but not adjustable. Could "shortening" the crank case breather assembly also cause rough running??

If you removed the fording system did you make sure to properly vent the fuel tank?

Yes..vented through the air cleaner.

http://home.comcast.net/~sday77/binky/index.htm

Thanks for direction to that site. Very informative.

Getting back to orginal question. What is rattling inside the valve?

The rattle is ok...it means the internal parts are free and moving. A normal check for a PCV valve is to shake it and listen for a rattle to make sure that the valve is not stuck (open or closed) with oil sludge. However, just because the PCV rattles does not mean you still don't have a problem...There are other signs to look for too.

Here's a pretty good page with info:
http://www.agcoauto.com/content/news/p2_articleid/197

That is a very good article. He hides the troubles symptoms a bit . One point he does bring up is simply replacing or eliminating the valve during other troubleshooting as in your case rough running is the easiest way to rule out the valve as your problem.

Also the original valves can be dis-assembled and cleaned and inspected. Just screw them apart.