what size allen key to open oil drain?

[tristantumble]

hi, i had a allen key that i used every fall to open and drain my oil from my monster, but i can't find it this year...and don't recall the size of the old one that i need to replace.

any help would be much appreciated.

[ducpainter]

10 mm

[darkduc7]

+1

[Michael]

I don't know if it's the same on the newer Monsters, but on the older models the drain plug is a little bit bigger than 10mm.

If this is the case with yours, it wouldn't be a bad idea to replace the bolt with a more common size (because you'll never find a 10.5 allen wrench).

Also, a good tip is to put the magnet on the outside and not the inside. I just talked to a guy who had the magnet on his old bolt break off and was loose inside the engine.

[greenmonster]

but on the older models the drain plug is a little bit bigger than 10mm.

That means yours is worn and you need a new one, they are 10mm.
Always clean it & be thorough when loosen/fasten it.

[seevtsaab]

Since this thread may come up in a search - I'll share the tip I saw - I think - in DesmoTimes's manual -
if the hex wrench fit is loose you can oil & sand the wrench to achieve a tighter fit.

[Howie]

The drain plug on my old monster has been in and out a good 20+ times and is still fine.  The "10.5 mm." feel is because the hex starts larger and tapers down.  If you get the wrench in all the way and maintain upward pressure you will be fine. 

[Michael]

The drain plug on my old monster has been in and out a good 20+ times and is still fine.  The "10.5 mm." feel is because the hex starts larger and tapers down.  If you get the wrench in all the way and maintain upward pressure you will be fine. 

Even Chris Kelly says it's a "not quite 10mm hex ... it fits it, but not quite perfectly."

Ducatitech.com "HowTo" Ducati Oil Change

[ducpainter]

It's still 10 mm

[Speeddog]

It's still 10 mm

+1

My 10mm Craftsman allen driver has done at least 100 oil changes, never failed.

I suppose you could grind down a 7/16" for a *perfect* fit, but IMO not worth the time.

[greenmonster]

It's still 10 mm

+1.
Bought a new one once, 10mm Allen fits real good.
As said before clean & keep upward pressure and you should have no problem.
And do not over tighten.

[scott_araujo]

10mm but a little loose on mine too.  Only had one oil change before I got to it so I think it's always been like that.  Just make sure you seat the allen in the drain bolt completely before you trun it.  If you don't you may open it up even more and eventually strip it.  My guess is it is sand cast which makes it both slightly tapered and not a perfect fit.

Scott

[jleong28]

+1 on the loose fit for 10mm.  If I bought a new plug, wouldn't it also be the same loose fit as the plug I have?  Is there an option to buy a 10mm plug as opposed to the 10.5mm one?

[Popeye the Sailor]

Does it really matter?

[Michael]

Does it really matter?

I think so.

Especially if you have an older model that's had a lot of oil changes in its lifetime. Even if you're careful, the 10.5mm bolt opening begins to get bent out of shape after a few years.