Re: [ihc] Re: 345 Oil drain holes clogged?

[Tom Mandera <tsm1@xxxxxxxxx>]

Jim Grammer wrote:

> Cleaning the drain back holes is somewhat complicated by the fact that head
> bolts run through them :(
>
> I've seen the edges of the holes rounded(Mandera), don't know if the actual
> bore was increased. Tom?
I didn't take any steps to actually increase the holes, I just 
"chamfered" the holes to promote better oil drain back.  If the holes 
were increased, it wasn't my intent.

Of course, when you're rebuilding, you'll usually be smart enough to 
change the oil regularly afterwards, and avoid the "12,000 miles beyond 
needing an oil change" coked up goo you find, thanks to the PO.

On my 392, I chamfered the drainbacks, but also Glyptal painted the 
valley so it would not retain oil (get it back to the pan faster), and 
then polished the con-rods so they'd shed oil better, too.. all to get 
the oil back into the pan ASAP, since the 392 lives at 3500rpm.