Getting a collection of gear lube in very rear bilge area. To be sure, I cleaned it up, went for a 2 hour spin/float on lake, have a good coating of fluid behind Stbd motor in the bildge. Gear Lube bottle is actually mounted on inside of transom, behind motor 2007 525efi. Fitting and nut at bottom of bottle not loose. Tried to follow the hose, but it kind of disappears (into the transom).

So, the question is, where are the potential sources of leak downstream from the bottle?

Thanks.

The hose goes to the fittin' on the transom, to the drive,....

Only other source would be the input shaft seal leakin' into the bellows, fillin' it 1/2 full, 'n drippin' into the hull along the drive shaft,..

Thanks will try to assess.

saw in another thread where some bottles leak around the wires where they come out the bottom of the bottle. Applies to bottles made in the last six years or so,

This is what I did when my Donzi was losing drive lube. I bought an extra cap, drilled a hole in it and installed a generic tire valve(has o-rings) from the local tire shop. I put this cap on and pumped it to 5lbs and looked for the leak. Used it every spring after that to check for leaks before putting the boat in the water.

That is a great idea for the pressure test if necessary. I presume there is pressure in the drive lube system when running? Will look around with a mechanic's mirror since the issue is in the back, behind the engine, at transom, leaking into bilge.....Think the issue is down low since top area does not appear oily with fluid and fitting at bottom side of bottle (although a tad bit of fluid on the threads), doesnt look real wet or dripping.