We miss you, Steve Z.
When I was a lad, playing 1st edition AD&D, golems were flesh, clay, stone, or iron. It wasn't until I discovered Moldvay/Cook years later (my "Basic" had been Holmes) that I found out about bronze, wood, amber, and bone golems; not to mention living statues.
To me, these somehow underscore "Classic" D&D's distinct flavor, especially B/X's. There's a weirdness to B/X that always seemed lacking in AD&D to me. Maybe it's the artwork, maybe it's the more streamlined rules, but some of these critters were just more wild and FUN to me. I'm sure that's just a personal bias, but there it is.
Anyway, on to old tanglebones here (that's for you Moorcock fans).
Bone Golem (from Cook Expert)
Move: 120' (40')
Atk: 4 (weapons)
Dmg: by weapons
No. App: 1
OK, first off. One of the things I love about the BG is that it looks kind of like an undead, but it's not. So clerics might waste time trying to Turn Undead or people might waste holy water (Or does one dare hope a Protection from Undead scroll?) on the thing. Also, in my games undead radiate evil for Detect Evil purposes, and this fella doesn't.
Next up, it's got all the great golem immunities: sleep, charm, hold, gas, and non-magical weapons.
Each golem type listed in Expert has a fun little ability or twist to it. Granted the wood golem's are disadvantages (fire and poor initiative), but I still appreciate the extra effort in the details. The Bone Golem's is 4 attacks per round (!) due to extra limbs grafted on. It can only target two people at a time, but still! Even with smaller weapons like shortswords, the thing is a macabre Cuisinart. 8 HD means it's attack rolls aren't too shabby either. A fun twist is the option to give it two 2H weapons (e.g. polearms) and let it do more damage per attack with only 2/round.
It's AC is decent but not unhittable. Again, 8 HD means it's probably in the fight for a little while.
Its Treasure Type -like all golems- is Nil, which means players may want tot think carefully about whether engagement is worth the effort.
So, tactics for it and to fight it?
As a GM, I would place this as a guardian for some tomb or temple. Maybe the bones of heroes were used to serve the cause without foul necromancy being involved. Tactically, it might appear as a pile of bones in an ossuary, magically assembling itself if the sacred place is desecrated.
"Creating a golem is costly, time consuming, and beyond the power of player characters in the D&D Expert rules." (X33) So they shouldn't be random fodder or too casually placed in the game. Someone, at some point, went to a lot of effort to put it wherever it is, so make it count.
Depending on the group it faces, it might focus all four attacks on one PC at a time until it drops the strongest foe, before moving on.
Fun thought #1: Give it two swords (1d8 each under the variable damage rules) and a longbow in the other pair! If you allow missile attacks while engaged in melee, the thing can be peppering the mage with arrows while fending of the melee types.
Fun thought #2: Cover the BG in armor head to toe. Even if it doesn't affect its AC, it may take the PCs a little longer to figure out what they are dealing with.
Fun thought #3: Use up one hand to give it a shield for -1 AC.
Fun thought #4: It's a walking weapons rack. The magic weapons in the treasure hoard are the ones it's using. If the fighter wants that shiny +2 longsword, he's going to have to beat the thing wielding it. I once gave a Bone Golem a +1 battle axe and a +1 glaive. The dwarf (I let them use battle axes as traditional weapons despite their @h status) and polearm-favoring fighter PCs were very happy after they beat the thing. The dead thief's player, not so much.
When facing the BG, players should have magic weapons and straight damage spells (fireball, etc.) available. Golems are nasty business in general. In most cases they have a specific task to perform and if you have to back off and come back better prepared, then do so. If you absorb some punishment, it shouldn't be too hard for non-beginner PCs to whittle down its hit points. Ranged attacks are your friend if it's sporting only melee attacks, and it's not too terribly fast (or slow) movement-wise.