Using gear lube like crazy!

[Cap'n Crunch]

5.0L MPI, Alpha 1. The gear lube reservoir is running empty after only 1 hr of use and setting off the alarm. I cannot see any leaks at the reservoir, at the line leading to the outdrive, at the vent screw, at the drain screw, at the gimbal bearing or at the prop shaft. With a loss of fluid that bad, I should be seeing fluid in the bilge or a serious film in the water and I don't see either. Who can toss me the magic answer here? Thank you in advance!!

 

[Jay1234]

Input shaft seal leaking into bellows. Done them on both my 5.0 alpha and helped a buddy with his 4.3 alpha that did the same thing last year. Grab a manual, you'll need a couple special Merc tools readily available on eBay. If it was an external leak there would be a ridiculous sheen on the water. Even a small leak. Not a bad project. Just follow the manual. There's guys on here that can go into a lot more detail than me.

 

[Cap'n Crunch]

Thanks for the reply, Jay. After doing some online searching, I have seen about 100 posts all over the internet regarding alpha and bravo outdrives leaking gear oil
...and all I can say is I seriously miss my trouble free bullet proof Volvo Penta.

 

[Bt Doctur]

They have their own issues too, Being a mpi, its probably a GEN II or a Bravo.
Pull the drive, drain , pressure test
For the GEN II try the seal under the water pump .For a Bravo prop seals or O ring
Either one is a "rotating seal " issue

 

[fastjeff]

I'd suspect the seal(s) below the water pump, or the shift shaft seal, is the culprit.

Jeff

 

[Cap'n Crunch]

Thank you Bt and Jeff. I assume it's a Gen II as it is an Alpha 1. If it's the seal below the water pump or the shift shaft seal, wouldn't I see the oil sheen in the water? When I discovered this problem I went thru and entire quart of gear lube in 4 hrs and there was no trace of it leaking either in the bilge or the water. Also, it only appears to be leaking under load. I appreciate the continued input...thanks!

 

[fastjeff]

Hard to see a sheen in the water behind the boat.

Jeff

 

[kevinj]

5.0L MPI, Alpha 1. The gear lube reservoir is running empty after only 1 hr of use and setting off the alarm. I cannot see any leaks at the reservoir, at the line leading to the outdrive, at the vent screw, at the drain screw, at the gimbal bearing or at the prop shaft.

Had a similar issue 2 years ago. No signs of leaks at any of the usual seals but gear lube was magically disappearing and setting off alarms.

In the winter '16-'17 I pulled the outdrive for a new gimbal bearing, trim senders, bellows, boots, etc. and finally found the problem. There are small plastic hose barb fittings on the outdrive and and gimbal housing with a small piece of tubing between them. This is your connection from the outdrive up to the gear lube reservoir. One of my hose barb fittings was cracked and when it was in the right trim position was mostly closed but in other angles leaked. The whole problem a little $2 part. sheesh......

I'm not saying this will be your exact problem, but it's definitely one place to look. If you put the outdrive up in the trailering position you should be able to see the little 1/8" tubing (I think on the port side). With the steering all the way to starboard use a flash light and can probably wiggle that hose a little and look for leaks either on the gimbal housing or the outdrive.

KJ

 

[harringtondav]

I'd bite the bullet, purchase upper and lower seal kits and re-work the entire O/D. You'll need special spanners, and a nut holder for the lower drive shaft nut, as well as seal drivers. If you don't have a manual, buy one from Merc. $90. Add up the cost of the tools and manual, and check the Marina's price on a seal job. It may be close, but you will be self sufficient for any future out drive maintenance. But get the manual. There are critical torque settings and procedures you don't want to overlook. You can get by with sockets as drivers for some of the seals, but the position and spacing on the double seal locations is critical.

 

[Cap'n Crunch]

Thanks Harringtondav. I paid the marina to replace all the seals and replace the exhaust bellow when it was discovered to have a crack. Total cost with parts and labor was $622.60. This included pressure tests and test drive in the lake. Hate spending the money but time was an issue for me and now it's good to go. Thanks everyone for your input.