Intermediate bearing coupler replacement

[mbalogh]

Hey everyone,

I’m in the process of replacing the intermediate bearing on my starboard engine. Got the assembly out of the boat no problem after reading all the great advice from this forum. However, unfortunately, the coupler on the assembly is so rotted that we couldn’t press the shaft out of the bearing housing. It actually broke just tapping on it! So now I need to order a new coupler and install it on the shaft. So I have a few questions:

1) It looks like from reading parts diagrams and the shop manual that the coupler threads onto the shaft. Are these standard threads or reverse threads? Or is there some other way it needs to be installed? Judging by the rotation of the impeller it looks like they should be standard threads to me.

2) The shop manual shows a tool that you insert into the shaft which engages with the splines to hold the shaft still so you can spin the coupler on/off. Anyone know where I can get one? It’s a Yamaha part number YW-38742. There are no Yamaha dealers near me that I can take this to to have this done.

3) I see two o-rings on the parts diagram. But I don’t know where they get installed. Are the two grooves shown in my second picture where those o-rings should be installed? Because there were none when I took the assembly apart, and I’m wondering if this is why the coupler rotted.





As usual thanks for all the great advice!

 

[mbalogh]

And now question 4, is this shaft any good? I pressed it out of the old housing and it seems like the area where the bearing’s rubber seals are is full of pretty significant grooves. The part that actually contacts the inner metal ring of the bearing seems fine. Is the shaft any good? Or is it going to leak because it doesn’t make good contact with the rubber seal?

 

[Acard7]

I would get on the phone with Partzilla or Yamahasportsplaza and see if they can send you a whole new driveshaft/coupler assembly. When looking at parts it looks like you buy them individually..

 

[Acard7]

Also, it leaked because your rubber seal and bearings on the intermediate bearing assembly were shot!

 

[mbalogh]

Very very shot! Good idea to look for an assembly. The individual parts are pretty pricey. And the more I look at this, the more I think I need a new one.

I’m super surprised the rubber seals inside the bearing assembly would groove the shaft like they did.

 

[Acard7]

Very very shot! Good idea to look for an assembly. The individual parts are pretty pricey. And the more I look at this, the more I think I need a new one.

I’m super surprised the rubber seals inside the bearing assembly would groove the shaft like they did.

My best educated guess is that’s what we get with pressure and heat plus unbalanced over time ???‍ Although my bearing assembly was horrible too but my drive shaft seemed okay!

 

[FSH 210 Sport]

Very very shot! Good idea to look for an assembly. The individual parts are pretty pricey. And the more I look at this, the more I think I need a new one.

I’m super surprised the rubber seals inside the bearing assembly would groove the shaft like they did.

How many hours did you have on that assembly?

 

[mbalogh]

I can’t be 100% sure because I just bought the boat, but the previous owner told me there were around 325 hours on the engines and I think this was an original part.

 

[Brad_Ct]

My shafts were not as bad as that but they were worn and I replaced them. Had around 400 hrs. on them.

 

[Mike's]

I would say when in doubt replace the part(s) Hope this helps -

 

[mbalogh]

So I finally got all the parts today to put my boat back together. One question, the new coupler has an 1/8” hole in the center. The old one definitely didn’t. So the only thing keeping water out of my boat will be the two o-rings inside the intermediate shaft. Is this correct?? Seems a little sketchy.

 

[Acard7]

So I finally got all the parts today to put my boat back together. One question, the new coupler has an 1/8” hole in the center. The old one definitely didn’t. So the only thing keeping water out of my boat will be the two o-rings inside the intermediate shaft. Is this correct?? Seems a little sketchy.

View attachment 181785

I kinda thought there was supposed to be a rivet in the middle there…But not 100% sure..

 

[mbalogh]

I know my old one was just solid in the center. And every. Single. Picture I can find of a coupler for the AR230, it’s solid. I haven’t even been able to find a picture of one with a hole in it.

The only thing I can think of is that Yamaha added a weep hole so that you would know if your O-rings were going bad. My last one rotted out because the O-rings were missing and salt water was getting to the coupler. But that seems a bit like jumping out of the frying pan into the fire. Now you’re just relying on O-rings to keep your boat from sinking. I’m very tempted to close the hole off with some 3M 4200.

 

[Brad_Ct]

Both mine had rivets in them, one of them came out when I was pressing the shafts out so I put a new one in. As stated they are 1/8”.

 

[mbalogh]

So I ended up getting this job done today! Finally!! I decided to put a rivet in the hole in the center of the coupler, don’t know if that was right or not but it seems the way the general consensus agreed it should be. The boat floats and there’s no leaks in the new bearing. The bearing on the other motor, that’s a different story. Seems like it’s leaking a bit at speed, but it’s dry when it’s sitting still. Gonna order the parts for that one and do that next.

Notes for those looking for advice on this project… I decided to take the two bolts out of the bottom of the engine mounts rather than remove the engine from the mounts. Yes, it’s twice as many bolts, but that went very well and I didn’t have to worry about the shims moving or being lost. However, one unintended consequence was that several of the motor mounts were torqued when they were installed. So when I tried to line the holes up to reinstall the engine I had to put pressure on the rubber to bend them a bit to make the holes lineup. It wasn’t a big issue, I got it done, but it wasn’t exactly easy.

The other thing I will say is stuff a rag at the back of the engine compartment behind the bilge pump at the very bottom. If you drop a bolt or nut, that is exactly where it’s going and if it gets too far you won’t be able to reach it and will have to pull the hatch on the swim platform to get it back. I was very lucky and was able to get mine with a magnet because I could barely see it.

Thanks again for all the great advice and help, not sure I would’ve taken this project on without it. You guys are awesome!

Mike

 

[Mike's]

So I ended up getting this job done today! Finally!! I decided to put a rivet in the hole in the center of the coupler, don’t know if that was right or not but it seems the way the general consensus agreed it should be. The boat floats and there’s no leaks in the new bearing. The bearing on the other motor, that’s a different story. Seems like it’s leaking a bit at speed, but it’s dry when it’s sitting still. Gonna order the parts for that one and do that next.

Notes for those looking for advice on this project… I decided to take the two bolts out of the bottom of the engine mounts rather than remove the engine from the mounts. Yes, it’s twice as many bolts, but that went very well and I didn’t have to worry about the shims moving or being lost. However, one unintended consequence was that several of the motor mounts were torqued when they were installed. So when I tried to line the holes up to reinstall the engine I had to put pressure on the rubber to bend them a bit to make the holes lineup. It wasn’t a big issue, I got it done, but it wasn’t exactly easy.

The other thing I will say is stuff a rag at the back of the engine compartment behind the bilge pump at the very bottom. If you drop a bolt or nut, that is exactly where it’s going and if it gets too far you won’t be able to reach it and will have to pull the hatch on the swim platform to get it back. I was very lucky and was able to get mine with a magnet because I could barely see it.

Thanks again for all the great advice and help, not sure I would’ve taken this project on without it. You guys are awesome!

Mike

Agree with the bolts for the engine mount - I did the same = the video a few post above will show how I did that