Drive Lube Leak

[Jmac572]

Ok, ever since I took delivery of my boat (Knot Working) in mid June it has had a persistent port side leak somewhere in the drive lube system. It's been "fixed" three times, one time of which included a full haul out and removal of the outdrive to replace a seal. That was a MAJOR service and I figured that fixed it. Nope. It leaks just as bad as ever, only while underway it seems, maybe slightlyyyyy while sitting in the slip. The reservoir is clean and no signs of fluid on or around it. It looks like its coming from the rear of the engine. Is there anything I can go check myself? Im getting sick and tired of this. The boat is still under Mercruiser's extended warranty for another 8 months, but it was guaranteed to be delivered in 100% condition as per the terms of the sale by Russo Marine in Boston (they are being very good about taking care of the issue, I'm just not sure why their mechanics are having such a difficult time. And every time it needs to go back I get put on the schedule a week or more out). The port side engine is also have a recurring "Port/Shift - Engine Misfire" alarm, the mechanics are TOTALLY stumped on what the issue is, but I'm wondering if its somehow related to the drive lube leak (oil getting on a sensor or electrical connection). Anyway, here is a couple pictures of the bilge, feast your eyes.... Three weeks ago the bilge was so clean you could eat off it.

The picture below shows the path the oil is taking from the rear of the engine into the center of the bilge.

 

[BillK2632]

Most likely cause of the gear lube leaking is the hose that runs from the reservoir, there is a quick disconnect fitting that passes that hose through the transom, where the hose connects to this fitting is probably the source of the leak. Be gentle with that fitting, it's plastic and they get old / brittle and can break and are a real PIA to replace.

 

[Jmac572]

Most likely cause of the gear lube leaking is the hose that runs from the reservoir, there is a quick disconnect fitting that passes that hose through the transom, where the hose connects to this fitting is probably the source of the leak. Be gentle with that fitting, it's plastic and they get old / brittle and can break and are a real PIA to replace.

Went down to the boat and checked that fitting today. Followed the line from the reservoir all the way to the transom. It was bone dry. I think it may be something serious, but only time will tell.

 

[BillK2632]

Are you sure it gear lube? Should be blue/green in color. Really the only way it could leak into the bilge is

1. Out of the reservoir cap if the cap seal is lost or damaged.
2. The lube hose or fittings (that you just checked)
3. Upper seal in outdrive is allowing gearlube to leak into the bellows, it will eventually make it's way into the bilge. If this were the case you would be seeing a lot of gear lube use. It would be coming in below where you just checked the hose/fitting, where the input shaft passes through the transom. If this is what the dealer fixed, they either didn't fix it or did not clean up the gear lube in the bellows and you are getting some residual leaking in. They key is if you are still using gear lube - a little gear lube use seems normal on an BIII, but if you are adding lube every outing, there is something wrong.

So to summarize, based on this and your other post, you have two problems:

1. The gear lube leak, which could be the seal not repaired correctly or residual gear lube not cleaned up in the bellows.
2. Raw water pump seems to be leaking, or something in the raw water circuit in that area. Could be a drain plug, but needs to be checked out - that's the stain below the bottom left pulley on your STB engine.

I would be persistent with your dealer, if these repairs were part of the purchase and you have a warranty, it's on them to get these resolved. Neither are major - yet.

 

[Jmac572]

Are you sure it gear lube? Should be blue/green in color. Really the only way it could leak into the bilge is

1. Out of the reservoir cap if the cap seal is lost or damaged.
2. The lube hose or fittings (that you just checked)
3. Upper seal in outdrive is allowing gearlube to leak into the bellows, it will eventually make it's way into the bilge. If this were the case you would be seeing a lot of gear lube use. It would be coming in below where you just checked the hose/fitting, where the input shaft passes through the transom. If this is what the dealer fixed, they either didn't fix it or did not clean up the gear lube in the bellows and you are getting some residual leaking in. They key is if you are still using gear lube - a little gear lube use seems normal on an BIII, but if you are adding lube every outing, there is something wrong.

So to summarize, based on this and your other post, you have two problems:

1. The gear lube leak, which could be the seal not repaired correctly or residual gear lube not cleaned up in the bellows.
2. Raw water pump seems to be leaking, or something in the raw water circuit in that area. Could be a drain plug, but needs to be checked out - that's the stain below the bottom left pulley on your STB engine.

I would be persistent with your dealer, if these repairs were part of the purchase and you have a warranty, it's on them to get these resolved. Neither are major - yet.

Thank you... It is definitely a gear lube leak, I have to add gear oil to the reservoir after every outing (like, a lot). I spoke with them yesterday and they are being very good about owning up to any issues, my frustration is that this problem was already addressed and I lose the boat for a week or more while its being fixed plus the dead time between each issue and until they can get a mechanic to address it. They sent a captain to my slip and ran the boat about 60 miles to their marina, had it hauled, pulled the drive, and replaced the upper seal, then filled my fuel tanks cleaned my bilge and ran the boat back to my slip, I'm very happy with their service I just wasn't sure how it could be the same problem again, but it appears it is. Maybe it was a faulty seal they used... Not sure. Either way its being ran up to Boston again tomorrow, by them, to be hauled and fixed. They are also dealing with the starboard raw water pump and the "Port/Shift - Engine Misfire" alarm. (That alarm has them and everyone else STUMPED, engine is running great, new plugs/wires/cap/rotor)

 

[Jmac572]

Are you sure it gear lube? Should be blue/green in color. Really the only way it could leak into the bilge is

1. Out of the reservoir cap if the cap seal is lost or damaged.
2. The lube hose or fittings (that you just checked)
3. Upper seal in outdrive is allowing gearlube to leak into the bellows, it will eventually make it's way into the bilge. If this were the case you would be seeing a lot of gear lube use. It would be coming in below where you just checked the hose/fitting, where the input shaft passes through the transom. If this is what the dealer fixed, they either didn't fix it or did not clean up the gear lube in the bellows and you are getting some residual leaking in. They key is if you are still using gear lube - a little gear lube use seems normal on an BIII, but if you are adding lube every outing, there is something wrong.

So to summarize, based on this and your other post, you have two problems:

1. The gear lube leak, which could be the seal not repaired correctly or residual gear lube not cleaned up in the bellows.
2. Raw water pump seems to be leaking, or something in the raw water circuit in that area. Could be a drain plug, but needs to be checked out - that's the stain below the bottom left pulley on your STB engine.

I would be persistent with your dealer, if these repairs were part of the purchase and you have a warranty, it's on them to get these resolved. Neither are major - yet.

So the dealer is replacing the Yoke Assembly on the port drive along with all the seals. They're also replacing the raw water pump in its entirety on the starboard motor and after running it up to the marina they were able to pull codes off the port motor to figure out the misfire issue and will be straightening that out as well. Hopefully were back to 100% after this round of treatment.