Gear Lube Leak Location? 6.2L

[Cmdunn7]

I know there have been a million gear lube questions on here but I haven't been able to find exactly what I have going on....

Boat is on stands getting ready to go in the water. Changed out the gear lube yesterday, and while cleaning up I noticed a decent amount of gear lube oil dripping from the plug hole in the bilge (which is is open since the boat is on stands) No leaking coming from the outdrive, or the gear lube monitor or connecting hoses. A check of the gear lube hose didn't yield anything either.

The boat and engine are practically brand new (2017) and I'm fairly new (5 years) at boating.

Any suggestions at how to mitigate this before pulling the stern drive off would be much appreciated.

 

[Luv2fish36]

If you started at the lube bottle and traced the hose all the way back to the transom with no leaks found I would Pull the drive off it's most likely coming through the U-joint bellows back in to the boat. Culprit would most likely be the carrier yokeshaft seal.

 

[Cmdunn7]

Okay , bear with me here, so the drive lube within the stern drive could possibly be leaking back into the boat through a broken seal/o-ring on the yoke shaft, which for clarification, is the longer splined yoke shaft that goes into the bellows? Would I just (hopefully) need to replace these seals, re-grease and reinstall the drive? As in #23 is the attached photo?

I'm just trying to visualize it so I know what I am getting into before hand.

Again, any help is greatly appreciated.

 

[Bt Doctur]

oil leaking from the drive will pass thru the gimbal bearing , there are no shaft seals on the shaft or behind the gimbal bearing that stop oil

 

[Cmdunn7]

Hey BT,

What about the 3 O-rings on the yoke shaft? If those aren't designed to stop oil from entering the bilge and I cannot find any other source, what should be the next area to examine?

All the help is greatly appreciated.

 

[Bt Doctur]

the O rings have nothing to do with oil control. oil in the bellow can only come from #12 or a grooved #15. If you pull the drive and pressure test it the area will be very easily seen

 

[Cmdunn7]

Okay I'll start there...thanks for the help

 

[Luv2fish36]

Okay , bear with me here, so the drive lube within the stern drive could possibly be leaking back into the boat through a broken seal/o-ring on the yoke shaft, which for clarification, is the longer splined yoke shaft that goes into the bellows? Would I just (hopefully) need to replace these seals, re-grease and reinstall the drive? As in #23 is the attached photo?

I'm just trying to visualize it so I know what I am getting into before hand.

Again, any help is greatly appreciated.

No those are just o-rings for the input shaft. Your drawing is a little blurry but I believe the seal I'm referencing is #29 (Seal, oil). It's fairly common on the bravos. If you pull the drive it will be obvious. You'll see the oil leaking behind the u-joints. Not really a job for a beginner as there are special tools involved as well as specific torques, setting bearing preload and lining up clutch marks etc... also just getting a bravo 3 off and back on the boat without a toter hoist can in itself be very difficult as they weigh about 200lbs with props. (Assuming its bravo 3) you might consider a local reputable shop on this one.

 

[Cmdunn7]

Ok yeah I’m guessing that’s the best course of action here. Thanks everyone for the help this was a lifesaver!

 

[sickwilly]

Could it be that you just spilled some gear lube? How much came out. Has any new lube appeared?

 

[Scott Danforth]

if its a 2017, you should still have warranty. if so, talk to your dealer

you could have simply over-filled the system and when the sunshine hits the drive, that expanding gear lube has to go somewhere, which is usually out the cap of the reservoir.

 

[Cmdunn7]

So I spoke with Merc and since I bought the boat new in March of 2017 its out of warranty and the 3 year "limited corrosion" warranty doesn't cover it. It "may" be covered by their parent company but I have yet to contact them.

The service rep I spoke with said that I should double check the inside transom connections. He said that would fail before the gear lube seals. I'm heading back down now to do just that. I'm hoping that would be an easier DIY fix.

 

[Cmdunn7]

So I spoke with Merc and since I bought the boat new in March of 2017 its out of warranty and the 3 year "limited corrosion" warranty doesn't cover it. It "may" be covered by their parent company but I have yet to contact them.

The service rep I spoke with said that I should double check the inside transom connections. He said that would fail before the gear lube seals. I'm heading back down now to do just that. I'm hoping that would be an easier DIY fix.

 

[Cmdunn7]

Went back down to the boat today and re-traced the gear line....although I couldn't see it, I realized there was no clamp on the hose and thats when I realized the the plastic elbow was broken almost clean off. The hose was still connected by the plastic fitting was hanging on by a thread.

Took about an hour total to get it off, installing new on tomorrow.

Big thanks to the guys who helped out.