Valve guide clearance? Experts needed

[Jory]

I'm building a head for a 1.6NA motor. The original valve guides were worn badly beyond the point where knurling and reaming would get them back in spec, so I opted to replace the guides.

After pressing new guides in, most of the valves fit very snug, some won't even insert fully. However, two of the exhaust valves fit easily. I mic'd the exhaust valve stems and all of them measure at .312". All I can figure is that pressing the new guides in deforms them slightly, causing the inconsistent fitment.

I have access to reaming and knurling equipment, but don't know what size to knurl to. What clearance is ideal in these motors? Should I knurl and ream all of them to provide a consistent fit or just ream the ones that are tight? The wear limit of .051" seems ridiculous...

any help is greatly appreciated.

[Jory]

alright, I went ahead and reamed the guides. I just stepped up the reamer size until the valve fit easily.
When I measured the clearances, they ranged from .005"-.009", with most being in the .006-.008" range.
Is this acceptable for a diesel? I obviously don't want any more slop than I need, but I have to allow for thermal expansion.
Any input?

[ToddA1]

Bentley calls for 8.013mm (0.315") to 8.035mm (0.316") inside diameter.  I'm no expert; I'm quoting an A1 Bentley.

-Todd