2010 Yamaha 242 Limited S Jet Boat: Intermediate Shaft and Housing

[Josse L]

Hello, fellow Jet Boaters.
I'm rebuilding the Intermediate Shaft and Housing of the starboard engine of my Yamaha 2010 242 Limited S. The problem is that in the Service Manual the measures in this specific assembly are very confusing. I pushed the shaft on the bearing until the metal mark of the old bearing, and the shaft went 22.86 mm outside the bearing housing. I took the measurements on the installed assembly on the Port Engine and the shaft went out 21.09 mm, that assemble is in good shape. But the Service Manual say, or at least is what I interpreted, that the shaft should go out only 9.5 to 10.5 mm. Attached are pictures on the project in process. Somebody here has the final word in this puzzle?

 

[swatski]

Hello, fellow Jet Boaters.
I'm rebuilding the Intermediate Shaft and Housing of the starboard engine of my Yamaha 2010 242 Limited S. The problem is that in the Service Manual the measures in this specific assembly are very confusing. I pushed the shaft on the bearing until the metal mark of the old bearing, and the shaft went 22.86 mm outside the bearing housing. I took the measurements on the installed assembly on the Port Engine and the shaft went out 21.09 mm, that assemble is in good shape. But the Service Manual say, or at least is what I interpreted, that the shaft should go out only 9.5 to 10.5 mm. Attached are pictures on the project in process. Somebody here has the final word in this puzzle?

I have no idea.
But, if you allow some speculation - if the coupler fits snag with the rubber coupler dumper/insert, and the impeller shaft fits inside the (? Female part of the coupler shaft?) far enough to place the impeller inside the wear ring where it needs to be - I would probably go by the wear ring / impeller position - as that is not adjustable, I think...
Again - total speculation!
Maybe Jeff @Cobra Jet Steering LLC would know the answer??

And just out of curiosity - what was the reason for the replacement? Water intrusion due to over loading with grease/blown seal? Was the engine aligned properly, did it move in its mounts hitting waves? Etc.

—

 

[swatski]

Also - maybe there are some clues here? IDK

https://jetboaters.net/threads/repairing-damage-and-a-leak-caused-caused-by-a-rope-being-sucked-into-the-impeller.18078/

 

[Josse L]

I have no idea.
But, if you allow some speculation - if the coupler fits snag with the rubber coupler dumper/insert, and the impeller shaft fits inside the (? Female part of the coupler shaft?) far enough to place the impeller inside the wear ring where it needs to be - I would probably go by the wear ring / impeller position - as that is not adjustable, I think...
Again - total speculation!
Maybe Jeff @Cobra Jet Steering LLC would know the answer??

And just out of curiosity - what was the reason for the replacement? Water intrusion due to over loading with grease/blown seal? Was the engine aligned properly, did it move in its mounts hitting waves? Etc.

—

This assembly can't be adjusted on the run, should be completely done before installation and of course, if it is wrong the impeller shaft and assembly will not fit in place. That is the reason of my question. In fact, I made the mistake of mounting the shaft on the bearing, not with a press but with a heat gun and there is no way to move it from the actual position without damaging the bearing. There is 1 mm of difference with the second engine. Tomorrow I will assemble the whole pump. I think that that mm won't be a problem. If somebody here knows the real measurement it's too late, at least for this time.
Yes, I have the Service Manual, but that section is a mess.
I detected it by water intrusion, but I think that the whole assembly was destroyed inside long time ago, I really don't know. I bought the boat a year ago, with so many problems that I have been correcting and repairing it since. I sold my 2005 sr230 to buy this 2010 242 and I regret it.
I apologize for my grammar, English is not my native language.

 

[swatski]

This assembly can't be adjusted on the run, should be completely done before installation and of course, if it is wrong the impeller shaft and assembly will not fit in place. That is the reason of my question. In fact, I made the mistake of mounting the shaft on the bearing, not with a press but with a heat gun and there is no way to move it from the actual position without damaging the bearing. There is 1 mm of difference with the second engine. Tomorrow I will assemble the whole pump. I think that that mm won't be a problem. If somebody here knows the real measurement it's too late, at least for this time.
Yes, I have the Service Manual, but that section is a mess.
I detected it by water intrusion, but I think that the whole assembly was destroyed inside long time ago, I really don't know. I bought the boat a year ago, with so many problems that I have been correcting and repairing it since. I sold my 2005 sr230 to buy this 2010 242 and I regret it.
I apologize for my grammar, English is not my native language.

This is very informative, thanks for posting and I hope you’ll keep us updated on the results. Not many posts on the intermediate bearing replacement but I have a feeling this is going to come up a lot more...

—

 

[Scottintexas]

@Josse L we're glad to have you on board, update your profile with your location so we know where you are,

be sure to check out our FAQ tab at the top of the page for lots of good do it yourself fixes,

We've only heard of one or two intermediate bearings/housings being replaced. Can you tell us what you actually did to rebuild and do you have any pictures or description of the broken one to give others an idea what to look for in the future.


.

 

[WREKS]

Did you have to remove the engine to remove the intermediate shaft?

 

[Josse L]

I did not remove the engine from inside the boat but I had to remove the bolts from the base and move it forward first and then rotate it about 15 to 20 degrees, you have to remove the impeller with the main shaft from the outside first, the same to reinstall the intermediate shaft back in reverse order. It will be easy to suspend the engine with a hoist and a leveler. I probably have to do it again on the second engine, and I'll do it that way.
The effort pays for itself, the engine is so quiet now, even quieter than some new boats.
This is the kit that I used for the rebuild.

YAMAHA Bearing Housing Repair 2008-2011 FX SHO HO Wvrnr FZR FZS 242 Ltd AR SX240 | eBay

2008-2011 FX SHO HO Waverunner FZR FZS 242 Ltd AR240 SX240 Models. 2010 Yamaha SX240 HO Bearing Housing Repair Kit. 2011 Yamaha SX240 HO Bearing Housing Repair Kit. 2009 Yamaha FZS Bearing Housing Repair Kit.

ebay.us

I also used CRC Sta-Lube SL3121 Water-Resistant Marine Grease to fill the housing, that grease is amazing!!!

PS: Be very aware of the original position of the SHIMS, (part 10 on the picture attached), could be several of them since it's used to aline the engine with the shaft. Take a picture before removing the housing, and mark in the picture how many shims are in each of the bolts. Will help in the reinstalling.

 

[WREKS]

Thanks @Josse L On your project, did the main shaft separate easily from the intermediate shaft?

 

[WREKS]

Hello, fellow Jet Boaters.
I'm rebuilding the Intermediate Shaft and Housing of the starboard engine of my Yamaha 2010 242 Limited S. The problem is that in the Service Manual the measures in this specific assembly are very confusing. I pushed the shaft on the bearing until the metal mark of the old bearing, and the shaft went 22.86 mm outside the bearing housing. I took the measurements on the installed assembly on the Port Engine and the shaft went out 21.09 mm, that assemble is in good shape. But the Service Manual say, or at least is what I interpreted, that the shaft should go out only 9.5 to 10.5 mm. Attached are pictures on the project in process. Somebody here has the final word in this puzzle?

@Josse L Yes, the service manual is very confusing, in error in parts, and lacks the information you need. Are both bearings pressed in? Maybe liquid nitrogen could be used on the shaft to release the seals and bearings. If you have to destroy bearings and seals, I would be checking a bearing company to see if you could get the parts for a lower price. Others here may offer some ideas.

 

[Josse L]

Yeah, more or less was easy, there was some corrosion inside the cavity but the remaining grease kept the main shaft loose. If there is no grease at all in yours, it could be difficult to extract the main shaft. The main shaft is a built-in stainless steel alloy, a very strong alloy, almost indestructible. Thus should be in good shape.

Another reason for the lock of the main shaft could be a misalignment, which is also one of the reasons for the failure of bearings inside the housing due to vibration, besides the lack of grease, which is usually the main reason.

In the service manual, there is the clearance measurement in the alignment, attached is a screenshot of that page on the manual.

When you assemble back the intermediate shaft, secure and tighten the engine first in the original position using the big shims in the base, exactly as from factory, then rotate the intermediate shaft housing back and forth, till is rotating in perfect alinement, then slowly screw the housing to the hull looking for the gaps in all three bolts, install the shims in the original order and check if the housing still aligned, if not, remove the shims and let the closest side of the housing touch the hull, then tighten that bolt a little, then put the SHIMS on the two remaining bolts covering the gaps completely, if you don’t have enough shims, buy more, DO NOT, and this is very important, force any of the two remaining bolts to touch the low intermediate transom in the hull, that is the key to align the shaft. Probably in the factory they use another method, but that method is not perfect since this problem is very common in the destruction of the bearing in the housing. You will be amazed at the result!

 

[Josse L]

@Josse L Yes, the service manual is very confusing, in error in parts, and lacks the information you need. Are both bearings pressed in? Maybe liquid nitrogen could be used on the shaft to release the seals and bearings. If you have to destroy bearings and seals, I would be checking a bearing company to see if you could get the parts for a lower price. Others here may offer some ideas.

Yes, both bearings are pressed in.