Recessed Allen Head Nut?

[Guest Fly4hire]

I'm curious as to the nature of the recessed allen head nut on the cylinder heads, and the large allen head cover to the bolt.

 

Why is there a need for a cover, and what is it covering?

 

Is this simply a recessed space required by design of the heads and the cover is to keep it from filling with oil?

 

Or is the actual bolt in the compression area of the cylcnder head? (don't think so because the bolt is and cover underside are clean when accessed)

 

The nature of the cover and nut have bearing on torgue required, which according to Lex's web site is 15 ft/lbs (no reference value in the manuals), but was torqued to almost the same value as the head nuts themselves when I accessed it for the first service.

 

I'm probably overthinking this, but I like to understand the how and why of the internals.

[Guest ratchethack]

Fly, somebody correct me if I'm wrong, but I believe this is a solution to one of those odd little engineering puzzles that just adds to the pile of stuff that makes Guzzi's unique in oh so many ways.

 

I reckon it's what they came up with to allow the oil galleries in the heads to be optimally placed and/or ease manufacture of the head castings. What the "cover" does is seal off the cavity below, which is actually part of an oil passage, wherein lies the recessed socket-head bolt.

[Baldini]

I may have misunderstood but is Fly4Hire talking about the top cylinder stud which has a socket head column nut. Large socket head screw in head allows access to that & it's there to keep the oil in.

 

KB

[Guest ratchethack]

I may have misunderstood but is Fly4Hire talking about the top cylinder stud which has a socket head column nut. Large socket head screw in head allows access to that & it's there to keep the oil in.

 

KB

56611[/snapback]

No misunderstanding, Keith. Except I called it a bolt, couldn't remember exactly what it is, but I know I had to get a little "creative" to get proper torque on it.

[Guest anawrocki]

When I did my first service I scratched my head on this as well. I ended up finding a hardened allen wrench that was the right size and long enough (10 mm if mem serves correctly, and cut it off and put a socket on it to torqe it to specs.