Yamaha f250- lower end oil drip

[pescador]

I’ve been cleaning the boat this week and notice a few drips of oil on the skeg coming out of the lower unit. The motor just had its 100 hour check then a few hours later was winterized. All was fine. I could see a minor trail of oil from the screw port where you fill the lower unit. I opened it and it burped out a couple of tea spoons of oil. I tighten it back down and cleaned things up. Over the winter the motor was slightly tilted up and I didn’t notice anything at all. It was when I dropped the motor vertical I noticed the drip. I’m wondering if Sherwood overfilled the lower unit and it’s just made it’s way out and it dripped into the water intake. It’s just a few drips a day.

1.0. Now that I have the motor in a vertical position is the oil just finding it’s way out of the water intake That accumulated over the winter?
2.0. Is the screw gasket faulty?

 

[profisher]

Easy enough to put a new gasket on the drain screw and eliminate that. Just have it ready to switch when you remove the old. You will only loose a couple drops of gearoil in the process. Just check the oil after the season for any traces of water.

 

[donnie d]

I had a similar issue on my kicker last year. Took the new gasket off, noticed pieces of old residual gasket from prior change was still bonded to the screw...over torqued in the past maybe? Removed that and put a new gasket on, solved issue.

 

[pescador]

So I’ve now figured out it’s dripping from the starboard side water intake. One drip every two hours. Does anybody know if overfilling can leas to this symptom?

 

[Buckethead905]

So I’ve now figured out it’s dripping from the starboard side water intake. One drip every two hours. Does anybody know if overfilling can leas to this symptom?

It’s going to be your drive shaft carrier bearing seal. There is a little stainless spring retains pressure against the drive shaft, after time it will eventually break from corrosion and allow oil to pass by.

 

[noluck]

It’s going to be your drive shaft carrier bearing seal. There is a little stainless spring retains pressure against the drive shaft, after time it will eventually break from corrosion and allow oil to pass by.

100 hrs on a brand new engine, seems weird to be corroded

 

[noluck]

it don't think it is possible to over fill,

 

[profisher]

You can't overfill as any excess will puke out the upper vent screw. If it is a newer motor take it back for warranty fix. Send same pics to Sherwood first so you aren't wasting your time if it is something simple and of no concern

 

[pescador]

I doubt its corroded. It like new this motor. Its only had one years full use. I'll get ahold of Sherwood. They've always been great to deal with.

 

[Buckethead905]

I doubt its corroded. It like new this motor. Its only had one years full use. I'll get ahold of Sherwood. They've always been great to deal with.

Doesn’t necessarily mean that the seal didn’t fail for some other reason. Have you confirmed that is in fact gear oil and not engine oil? If it’s engine oil then that would likely be the oil pump which is located on the bottom side of the power head if I remember. If it is gear oil you have only 2 seals for it to leak, the prop shaft seal, and the upper drive shaft seal, if it’s not leaking out of the inside of the prop shaft seal let’s use process of elimination...... drive shaft seal.

 

[pescador]

Something has failed. It’s under warranty. I’ll let them deal with it. Thanks for input guys.

 

[timbuk2]

Just a tidbit, when storing in winter, motor should be tilted all the way down.

 

[ship happens]

If there is gear oil in the water passage, the driveshaft seal is leaking.

I agree that you need to find out if its engine or gear oil. Smell it

 

[pescador]

If there is gear oil in the water passage, the driveshaft seal is leaking.

I agree that you need to find out if its engine or gear oil. Smell it

Thanks for the response. Its gear oil for sure. That smell is quite different to motor oil. Hard to believe a driveshaft seal would go at 140 hours on a 2019 model year motor. I haven't had a chance to take it in yet, but, doing some sleuthing on Youtube I see the drain plug for the lower unit is on the right side of the water inlet (starboard). Thats the side the leak is coming out of. Not the left. I just wonder now if the guys didn't tighten the drain screw or used an old gasket?

 

[ship happens]

Pressure test

 

[noluck]

Thanks for the response. Its gear oil for sure. That smell is quite different to motor oil. Hard to believe a driveshaft seal would go at 140 hours on a 2019 model year motor. I haven't had a chance to take it in yet, but, doing some sleuthing on Youtube I see the drain plug for the lower unit is on the right side of the water inlet (starboard). Thats the side the leak is coming out of. Not the left. I just wonder now if the guys didn't tighten the drain screw or used an old gasket?

loose drain screw would be my guess,

 

[pescador]

Thanks. I bought 6 new gaskets yesterday. They are one time use only the dealer said. $2 each and they're black all right. I’ll pull the water inlet plastic screen next week and check the drain plug for sure.