intermediate bearing replacement info.

[Riveramx]

This intermediate bearing replacement has been tough, but I finally finish one engine. waiting on the other intermediate bearing to arrive to do the second engine. Tested the starboard engine after replacement and it runs really smooth and quieter. really happy with the results. I am including the part numbers in case they are needed.

 

[FSH 210 Sport]

How many hours on these bearings?
Did you grease them ?

 

[Riveramx]

What I found out is that from the drive shaft to the intermediate bearing housing it gets filled up with water while the boat is in operation. Where you attach the bearing it does not have a way to drain the water on the lower part of the bearing. Due to this, I would recommend more frequent greasing of the bearing (maybe every 12 to 24 hours of operation and just before extended storage) and also doing a visual intermediate bearing inspection every year; preferably at the end of boating season, so if there is a problem you will have ample time to get parts and work on your boat before boating season starts again.

 

[Riveramx]

This part that the intermediate bearing attaches to gets filled up with water during operation. You can tell by the water mark on the intermediate bearing where the water settles after engine shutdown. I am thinking of a solution for this is either install a mechanical seal or making a modification where this section can be flushed and drained.

 

[FSH 210 Sport]

Got it.. how many hours did you have on this bearing?

I asked about whether or not you greased these as I can see no evidence of grease anywhere on the bearing holder, the ball bearing cages look rusty, even the little hole where the grease comes in at from the zerk looks perfectly free of grease.

 

[Riveramx]

That was my fault. I was told not to over grease the bearing and that I could damage it if I did. I was also told to grease it a couple of pumps and that would be enough once or twice a year from the guy I bought it from. I assumed that the bearing was sealed because if you over grease a bearing you could blow the seals and damage the bearings. This bearing is not sealed. it has a thrust washer with a rubber coating against it and that's it. As long as the grease doesn't come out in the front of the bearing it should be okay. I tested it and basically any over grease goes into the cavity behind the bearing.

 

[anmut]

Well isn't that interesting. The "2-3 pumps only" I believe is in my manuel. I bought myself a cheap little remote camera for my phone - this will for sure be part of my Spring inspection.

 

[Riveramx]

Well isn't that interesting. The "2-3 pumps only" I believe is in my manuel. I bought myself a cheap little remote camera for my phone - this will for sure be part of my Spring inspection.

I removed the air intake box to make it easy to slide the engine back next time, modified with a different intake as shown in the pic. What I did was remove the two bolts that hold the engine mounts to the hull, lubricated the area in front of the engine mounts with wd-40. After disconnecting the water hose discharge from the engine, the small hose that brings water from the jet and the exhaust rubber boot I just slide the engine forward. make sure the boat is level before moving the engine. I used blaster surface shield for the area behind the bearing. I used marine grease for the bearing itself.

 

[Riveramx]

Starboard engine has 323.5 hours. This is what is sounds now after replacing the intermediate bearing. Much quieter and smoother.

 

[joep411]

Starboard engine has 323.5 hours. This is what is sounds now after replacing the intermediate bearing. Much quieter and smoother.

Was it hard to do?

 

[Riveramx]

Was it hard to do?

not really. if you remove the engine compartment hatch is easier to do (More room to move and see).

 

[Riveramx]

not really. if you remove the engine compartment hatch is easier to do (More room to move and see).

let me know if you need any help or tips. I'll be happy to help.

 

[Cobra Jet Steering LLC]

The bearings are definitely sealed and a good one does not get any water in it as water will ruin the bearings thus the gear lube in the housing to liquify the grease and keep those bearing seals lubed so they do not leak or go bad.

 

[Riveramx]

The bearings are definitely sealed and a good one does not get any water in it as water will ruin the bearings thus the gear lube in the housing to liquify the grease and keep those bearing seals lubed so they do not leak or go bad.

I disagree. those are just regular roller bearings. If they were sealed there will be no need for a grease fitting. see the difference below:

 

[Cobra Jet Steering LLC]

Ok I misunderstood what you were saying, I thought you were saying the bearing housings did not have seals ,yes the bearings are exposed inside the housing.

 

[FSH 210 Sport]

@Riveramx thanks for making this thread ! It removes a lot of mystery about this subject in real pictures. The manual has this exploded view, but I’d never thought that the design would allow water to sit in that area behind the bearing holder, but I can also see the wisdom of that design, it allows the lovejoy connector on the intermediate shaft / bearing side to float while being suspended on an isolation bushing.


The two O rings, part #3 in the exploded view, do those go on the outside of the intermediate shaft, inside? Can you please explain what their purpose is? I think I can see them here.



My manual is specific about how much marine grease to add at the 10 hour mark, I think it’s 33 or 35 CC’s, then a very small amount every 100 hours or annually. What is obvious is that this bearing needs lubrication, this bearing spins at whatever rpm the engine is turning, at WOT that’s 7500-8000 rpm, at cruising speeds it’s around 6000 rpm plus or minus. Now I pull the zerk fitting out and use a piece of weed wacker line to check the amount of grease that’s in the housing at the maintenance intervals and add grease accordingly.

Did you grease the new bearing assembly before you installed it?

Very helpful info on how to move the engine forward to get enough room to R&R the bearing assembly.

Well done!

 

[Riveramx]

@Riveramx thanks for making this thread ! It removes a lot of mystery about this subject in real pictures. The manual has this exploded view, but I’d never thought that the design would allow water to sit in that area behind the bearing holder, but I can also see the wisdom of that design, it allows the lovejoy connector on the intermediate shaft / bearing side to float while being suspended on an isolation bushing.

View attachment 232799
The two O rings, part #3 in the exploded view, do those go on the outside of the intermediate shaft, inside? Can you please explain what their purpose is? I think I can see them here.

View attachment 232800

My manual is specific about how much marine grease to add at the 10 hour mark, I think it’s 33 or 35 CC’s, then a very small amount every 100 hours or annually. What is obvious is that this bearing needs lubrication, this bearing spins at whatever rpm the engine is turning, at WOT that’s 7500-8000 rpm, at cruising speeds it’s around 6000 rpm plus or minus. Now I pull the zerk fitting out and use a piece of weed wacker line to check the amount of grease that’s in the housing at the maintenance intervals and add grease accordingly.

Did you grease the new bearing assembly before you installed it?

Very helpful info on how to move the engine forward to get enough room to R&R the bearing assembly.

Well done!

Hello and thank you for your kind words. I am here to help.

okay, the picture where you put the arrow is the cavity where the grease goes. in front of it there is a shaft seal.
the two little o-rings goes inside the "female" shaft that takes the impeller shaft with the splines. The purpose of this o-rings is to prevent the water from washing the grease in the splines. the splines delivers the torque to the shaft and and goes in and out depending on the expansion of the impeller shaft. this grease is essential and I use green water resistant grease. Yes I pack the grease on the bearing before installation. pack it really good.

 

[FSH 210 Sport]

Hello and thank you for your kind words. I am here to help.

okay, the picture where you put the arrow is the cavity where the grease goes. in front of it there is a shaft seal.
the two little o-rings goes inside the "female" shaft that takes the impeller shaft with the splines. The purpose of this o-rings is to prevent the water from washing the grease in the splines. the splines delivers the torque to the shaft and and goes in and out depending on the expansion of the impeller shaft. this grease is essential and I use green water resistant grease. Yes I pack the grease on the bearing before installation. pack it really good.

Perfect thanks!

I suspected as much but could not see the grooves on the female shaft until your pictures. That makes total sense, and why the service manual calls for Molybdenum Disulphide grease to be packed into the splines before installing the shaft.

Again, much thanks as I now have a much clearer understanding of how this assembly works.

 

[Riveramx]

Okay, continuing on with my findings. And for those who may think I am winging this thing, I have a marine mechanical systems engineering certification from the US Navy in which I served 20 years as a machinist mate in nuclear power submarines, ASE certifications as a car mechanic and was a civilian contractor in charge of all the maintenance and modifications to various US Navy and Coast Guard Small crafts and ships. So, the grease fitting is really injecting grease between part #5 and #8 of the above exploded view of the intermediate bearing. I inserted a zip tie to illustrate. This means that the grease is not directly injected into the bearing but to the cavity between part#5 and #8. I seriously doubt much grease will reach the bearing this way. A better location to me would be forward of bearing. I am going to Drill tap and install a grease fitting in front of the bearing. Unfortunately it will have to be a while because I have to do some travel, but when I get back I'll let you know how it goes. In the mean time I am open to questions and suggestions.

Thanks, Miguel.

 

[Cobra Jet Steering LLC]

I have numerous posts about adding gear lube to your intermediate bearing grease by removing the fitting and using a syringe to add it to liquify it better and avoid causing damage look at the hole for the grease it goes through the aluminum housing and the rubber that is adhered to the housing since there is no vent the pressure can and does separate the rubber from the hosing and then water gets inside. The grease being liquified also helps to lube the seals better than grease and it helps the grease come back to the moving parts that need it.
Here is a picture of one housing that separated .
note the hole for the fitting and I have the inner piece pulled forward so I could show where the grease travels and works into the area between the rubber and the housing under pressure. Remember this is supposed to be a single unit not separate. Here are the parts laid out
The rubber section is actually a vibration dampener between the bearing and the housing. Also add gear lube to your jet pumps to greatly increase the longevity of the bearings in that as well by liquifying the grease there .