How much slack??

[2ndnissan]

I just bought a used ka24e. Engine had been sitting for a year or so but appears to still be in pretty good shape. Owner said it had just 62,000 on it before being pulled for a swap to an sr. I had to replace the freeze plugs because they looked a little iffy and the water pasages were a bit grunky. I took off the valve cover to check the timing chain as I really did not want to install it THEN find a problem.

The question is this: How much slack is acceptable in the chain?

It's tight on the tensioner side but has about a half inch play at the bottom(I did take off the cover to inspect). There is also about 3/8 inch of play at the top. The guide is in good condition on the side that isn't in contact with the tensioner. Would that slack go away after the tensioner actually had some oil pressure on it? Should I just change everything just to be safe? Should I also change the oil pump since it is off now to take off the timing cover?

[sx moneypit]

As long as you've got it out you might as well go ahead and at least put a chain kit in it.It is a helluva lot easier to do it now!