Oil in bellows questions…

[TomB985]

Good evening, everyone.

I pulled the drive this evening to check over the U-joints and gimbal bearing. My new boat makes a bit more noise than I’m used to when turning under throttle, so I wanted to check it out. The good news is that the U-joints and gimbal bearing are smooth as glass, so the noise is probably normal.

Bad news is the bellows were filled with oil. The drive was supposedly replaced by the previous owner in 9/2021, but they were a fleet operater who put a ton of hours on. I’m pretty handy, but I don’t really have the tools or experience for gearcase and bearing work, so I’m leaning towards taking this one in. I have a couple of questions that I couldn’t find with the search, so I hope you guys will humor me for a bit.

First, will a pool of gear oil in the bellows trash the gimbal bearing over time? No evidence of an issue so far, but I‘d like to know if it’s on borrowed time.

Second, the stickie at the top of the forum has a great thread by ahris on common oil leaks. If I’m reading this right, I’d need to disassemble the upper bearings to replace this seal?

And lastly, it looks like the price of an SEI upper has gone down a bit since I last looked. The SEI lower I put on my last boat a few years ago made some gear whine, but never gave me any trouble. Is the cost likely to be high enough that a replacement would make more sense?

I’m trying to figure this out before leaving on a road trip with my boys next Wednesday, and we’d really like to have the boat ready to use shortly after we get back. Boating season isn’t real long in Minnesota.



Thanks!

 

[Bondo]

Ayuh,.... 1st, No, it won't hurt the bearing,....
2nd, Yes, it has to come apart to change the seal,...
3rd, I donno,....

 

[flashback]

I have an SEI upper and lower but not long enough to give a star, it does whine a bit but suspect it will quiet down after it gets comfortable..

 

[Dubed]

I have an SEI upper and lower but not long enough to give a star, it does whine a bit but suspect it will quiet down after it gets comfortable..

My friend owns a boat yard in RI. He told me they work fine but they are loud. He also said they had many issues with the impeller so they install MCM impellers before they leave the yard

 

[flashback]

That's on the menu this fall Dubed, I finally got this boat running well.. it's a keeper...

 

[TomB985]

I appreciate the quick responses, everyone. I’ll call around on Monday to see what local shops tell me. It looks like an SEI replacement can be had for just over $1,000 after shipping, so if the quotes seem close to that, I might just replace it.

 

[nola mike]

$200 in parts and 4 hours if you've never done it, including buying a dial indicator.

 

[TomB985]

$200 in parts and 4 hours if you've never done it, including buying a dial indicator.

Now you’re giving me second thoughts.

From what I gather, I’d need a spanner wrench, yoke, seal, and O-ring for parts. Maybe a dial indicator and good in-lb torque wrench as well? Do any of these steps require a press?

 

[dubs283]

Cheapest route is to find a local, reputable shop to reseal the drive shaft housing.

Most likely be charged the afore mentioned flat rate of 4 hrs, parts separate. Hopefully that'd include a decent inspection of the transom assy/drive r and r

Heck, they'd probably find issues with the bellows too!

 

[TomB985]

The boat isn’t even five years old, so I’m pretty sure the bellows are fine. They look great from what I can see, and the gimbal bearing is as smooth as glass.

I just ordered a spanner wrench that will be delivered on Monday. My first glance yesterday of the service manual was kind of intimidating because it went through the entire process of tearing down the upper drive. I have a garage full of tools from 20 years of acting like an amateur mechanic, and a bunch of disassembly has never bothered me. I’ve never done any gearcase work, but this almost looks fairly easy after looking closer.

Am I understanding this right? Remove the retaining ring, then the top cover, and remove the yoke/shaft/bearing assembly. Remove the bolt and disassemble the bearing/carrier/seal pack, replace parts as needed, and re-assemble?

 

[TomB985]

Wait a minute…

I was looking over my photos from yesterday, and it almost looks like a gasket problem. There’s oil extending upward from the passage and into the hole going into the U-joint bellows.

Am I overthinking this, or is this a leakpath from a failed gasket? I can’t imagine how oil would go upwards when I removed the drive yesterday. The boat was new in summer of 2018, and the entire drive was replaced in September, 2021. It has 1,120 hours, but most of those were on the old drive, and it seems odd that I’d have a failure with such a new drive.

What do you guys think?

 

[dubs283]

You need more tools, especially special (proprietary) tools. Especially if you want to complete the job in flat rate time

Not sure of the bolt you mention, there is a nut that needs removed

No need for a dial indicator but you will need a dial torque wrench, 0-15 lb/in works best, decent quality

Read the manual, #14 will give you the broad strokes. Gen 2 current manual gives the fine points pertaining to your drive's vintage

Not sure where youre located but by my time you should be back on the water by late afternoon at worst.

 

[nola mike]

You need more tools, especially special (proprietary) tools. Especially if you want to complete the job in flat rate time



No need for a dial indicator but you will need a dial torque wrench, 0-15 lb/in works best, decent quality

Dial torque wrench, I misspoke. Only other proprietary tool I can think of is the castle nut remover?

 

[dubs283]

Right, retainer wrench is the tool needed. I was thinking full reseal which requires a bit more

Check list: pressure tester, drive stand, sae wrenches, drain pan, bent pick, oem parts in hand, air is nice but electric impact may suffice, large screwdriver, shop press, lubricants/sealers, oem manual(s).....

Roadshow is distracting me rn, probably missed some tools

 

[TomB985]

It looks like the driveshaft seal may not be the problem.

After thinking about it more, I put together a pressure testing rig from an old fuel pressure gauge. I drained the oil yesterday afternoon and pumped it up to 11 PSI. I rotated the shaft last night before going to bed, and 15 hours later, the gauge hasn’t moved.

I think it may have been the gasket I mentioned in post 11. The drive isn’t even two years old, so a gasket failure when they installed almost seems more likely to me.

 

[Scott06]

It looks like the driveshaft seal may not be the problem.

After thinking about it more, I put together a pressure testing rig from an old fuel pressure gauge. I drained the oil yesterday afternoon and pumped it up to 11 PSI. I rotated the shaft last night before going to bed, and 15 hours later, the gauge hasn’t moved.

I think it may have been the gasket I mentioned in post 11. The drive isn’t even two years old, so a gasket failure when they installed almost seems more likely to me.

View attachment 385545

You are correct if it holds pressure drive isnt the issue. You will get a small amount of spillage at the poppet valve in bell housing when removing and installing the drive

 

[TomB985]

You are correct if it holds pressure drive isnt the issue. You will get a small amount of spillage at the poppet valve in bell housing when removing and installing the drive

Right, but that wouldn’t explain the pool of oil in the bellows. It was more than a single paper towel could absorb; I couldn’t believe how much was in there.

I expected a trail of oil going downward from that hole because of spillage. The track going upward into the U-joint cavity is how I think it got there. I think I’m going to clean up the gasket surface, reassemble, and check again at the end of the season if my oil level moves.

 

[chs marine service]

the oil cant get into the cavity from the poppet valve . there is a ribber ring/gasket that sits against the bellows retainer ring and seals the unit stopping water from getting past.

 

[nola mike]

We know it's gear oil for sure, right? Level dropping in the bottle?

 

[ROY WILLIAMS]

It looks like the driveshaft seal may not be the problem.

After thinking about it more, I put together a pressure testing rig from an old fuel pressure gauge. I drained the oil yesterday afternoon and pumped it up to 11 PSI. I rotated the shaft last night before going to bed, and 15 hours later, the gauge hasn’t moved.

I think it may have been the gasket I mentioned in post 11. The drive isn’t even two years old, so a gasket failure when they installed almost seems more likely to me.

View attachment 385545

I was every year of the outdrive 10psi air gauge 24 hrs ...
also I was now in the impeller and then the outdrive gauge ...