Yamaha 30 - prop shaft thrust bearing replacement

[Blue Horizon]

I seem to have some bearing noise coming from the prop shaft thrust bearing. I'd like to put a new bearing in. Has anyone replaced that bearing or know how to source it? I have the Yamaha 30 - V-birth YSM12 model.

I'm hoping (perhaps naively) that the bearing itself is held in the housing, is replaceable, and is used more generally in other mechanical applications (in a common size) although probably metric.

(schematic attached below message)

I took my prop shaft out last summer to replace my stern tube and that was pretty straight forward so familiar with the other steps. Just need to figure where to get the part!

And for other parts like this has anyone come across a supplier (perhaps in Japan) for Yamaha 30 vessel parts like these?

Appreciate your ideas!

thanks all!

 

[Ralph Johnstone]

Is this bearing a part of the Yanmar engine or an add on for your particular installation ?

Never seen an installation with an external thrust block or is the drawing so schematic the thrust block is not drawn near the engine ?

Also, any reason why the prop shaft is shown exiting vertically through the floor in Fig. 32 while Fig. 29 shows all parts to be inline ? Or is it just my eyes ?

 

[Blue Horizon]

Is this bearing a part of the Yanmar engine or an add on for your particular installation ?

View attachment 206193

Never seen an installation with an external thrust block or is the drawing so schematic the thrust block is not drawn near the engine ?

Also, any reason why the prop shaft is shown exiting vertically through the floor in Fig. 32 while Fig. 29 shows all parts to be inline ? Or is it just my eyes ?

 

[Blue Horizon]

Hi Ralph,

Thanks for your note. It's the stock Yamaha prop shaft thrust bearing that mounts to a stringer in the bilge area of the cabin sole. You can see from the diagram it's an 11ft prop shaft that goes from the engine through a prop shaft bearing, the stuffing box and out of the vessel via the stern tube to an outside cutlass bearing.

 

[Blue Horizon]

the second image is a birds-eye view looking down at it.

 

[Ralph Johnstone]

the second image is a birds-eye view looking down at it.

It was the '"floor" label that lost me.

You may well be going in the right direction looking for the same bearing elsewhere. Yanmar does NOT make bearings. just hope they didn't have this one custom made. Any labels on the bearing once you get it out ?

That doesn't sound like much fun, or something you're going to remember every three months of usage. This sounds like an open bearing. May be worth looking for a sealed bearing if you can find one in the same size.

I imagine Stem to Stern can supply the bearing, but I'd hate to think of the price.

 

[kloudie1]

I have not put eyes on a Yamaha driveline, but as Ralph says, you probably have a standard bearing (or more likely two bearings for thrust) that are pressed into a holder. There should be some numbers on the housing that can point you to a replacement. The search term would be "Flange mount thrust bearing". Amazon has a selection and they can be locally sourced through a supplier like Motion Industries or Granger. The hard part is going to be getting it out so you can inspect it and or carry it to Motion Industries so they can find the correct replacement. It may be a problem that the shaft is 22MM in diameter but they should be able to find a metric size. Good Luck

 

[Blue Horizon]

I have not put eyes on a Yamaha driveline, but as Ralph says, you probably have a standard bearing (or more likely two bearings for thrust) that are pressed into a holder. There should be some numbers on the housing that can point you to a replacement. The search term would be "Flange mount thrust bearing". Amazon has a selection and they can be locally sourced through a supplier like Motion Industries or Granger. The hard part is going to be getting it out so you can inspect it and or carry it to Motion Industries so they can find the correct replacement. It may be a problem that the shaft is 22MM in diameter but they should be able to find a metric size. Good Luck

Hi Claude,

Thank you for this excellent insight! Great to know where to start on this, and just having the proper part description name as you've provided and some suppliers is super helpful. I've looked at a few online and they closely resemble what I have in there. Happily the bearing is actually quite easy to access on this boat.

I'll update this thread as I go and if anyone else has ideas here they are welcome.

The ideal solution is the bearing housing made 40 years ago (lol - ya I know..) To fit something else the flange bearing housing bolt holes will need to be re-sited and likely a couple of set screw holes correctly sited in the shaft - but that's just stuff to do (although carefully).

Thanks again!

Peter

 

[Blue Horizon]

UPDATE: Thanks to some great suggestions here it set me off on the right path. I did find the bearing and bearing housing. And I thought to complete the thread, I would let you know how I found it and what it is.

The bearing housing has a mark on it at the top "NTN" and at the bottom "FL305J". It's a Japanese bearing.

Surprisingly, there is an NTN Canada and contacted them as that's where I am and the bearing housings and bearings are still being made! It seems bearing housings and their bearings don't change as much as iphones. There was one in stock in Canada at this time. It's 8 months to order and have Japan make one.

Housing: FL305D1
Bearing: UC305D1

Price for both: CDN $486.09 or about US $360 (and probably cheaper if sourced in the U.S.). That was less than I expected.

There is a 22mm bearing that might match a 22mm shaft, but the one I've ordered is a 25mm bearing to allow for the additional collar Yamaha 30 has insitu (that the counter weights bolt onto) that slides between the bearing and the shaft. I measure that diameter at about 24.44mm. You should confirm your own measurements and make your assessment.

I haven't installed it yet. So certainly if you embark on this one confirm for yourself what bearings and parts would work for your boat on this before you order.

Yamaha 30's came in a couple of prop configurations mine being an early V-berth model. And they could also have changed year to year. Hope this has been helpful. And thanks again to those who chimed in on this one!

Happy Sailing!