Found some lube on my outdrive

[natsgrampy]

Have an 89 Sea Ray with a Mercruiser 3.0 Alpha outdrive MR I believe.

The other day was out on the water for about 10 hours. The next day I looked under the outdrive and found a small amount of what looked to be gear lube on the ground. The spot was about an inch around, size of a quarter. The drive is in the up position and it appeared the lube came from between the upper and lower unit.

This was the first time on the water this year. I changed the fluid in the unit before the season.

The boat was sitting in the sun all day it was 95 degrees that day. Could the heat have caused the unit to get so hot and expand the fluid so as to leak from the oil seal? The seal was replaced the beginning of last season Or, do I have to remove the lower unit and replace the seals? It hasn't leaked anymore since that one time.

 

[Don S]

Re: Found some lube on my outdrive

Could the heat have caused the unit to get so hot and expand the fluid so as to leak from the oil seal?

No, it gets hotter than that when it's running.

Best thing to do is remove the drive, drain the gear lube, the pressure test the drive. Use some soapy water and spray on everything and see where it blows bubbles. Turn the shafts, and the shift shaft while pressurizing. Pay close attention inside the front of the drive in the exhaust passage.

 

[natsgrampy]

Re: Found some lube on my outdrive

OK, so I pulled the drive and drained the gear lube. I have a small air compressor, use it for filling tires and sports equipment. Can this be used to pressure test the drive? Is there an attachment I can put on the end to do the test?

I can always buy a compressor from Harbor Freight. What do I use to attach it to the drive and how much pressure do I put into the drive to properly test it?

This is all new to me, so I'm learning all the time!

Thanks

 

[ktbarrentine]

Re: Found some lube on my outdrive

Try this link...it has the info you need. No need to use a compressor (you're only going to 15 PSIG). Use a small hand pump, like a tire pump.

http://forums.iboats.com/mercruiser...sure-check-prior-post-233546.html#post1573303

You will find that the threaded connection for the vent and drain plugs on your drive are standard 3/8-16 NC threaded ports. You can typlically use the threaded fitting off of your gear oil pumper to adapt to the pressure test device. I constructed a test fitting using a 3/8-16NC bolt with the head cut off and drilled through for an air passage. Glued on a nut and washer/gasket and it works fine.

By the way... this link is from the "adults only" sticky at the top of this mercruiser I/o forum. I suggest you visit that sticky. It has alot more info that will be helpful to you.

My bet is that it is your shift shaft bushing...but that is only because my crystal ball is in the shop. Do the detailed pressure test and take your time. Good luck!

 

[ktbarrentine]

Re: Found some lube on my outdrive

Could the heat have caused the unit to get so hot and expand the fluid so as to leak from the oil seal?

Note: there are several seals that are potential suspects....