• Welcome to Jetboaters.net!

    We are delighted you have found your way to the best Jet Boaters Forum on the internet! Please consider Signing Up so that you can enjoy all the features and offers on the forum. We have members with boats from all the major manufacturers including Yamaha, Seadoo, Scarab and Chaparral. We don't email you SPAM, and the site is totally non-commercial. So what's to lose? IT IS FREE!

    Membership allows you to ask questions (no matter how mundane), meet up with other jet boaters, see full images (not just thumbnails), browse the member map and qualifies you for members only discounts offered by vendors who run specials for our members only! (It also gets rid of this banner!)

    free hit counter

Driveline help

Hoppy

Jet Boat Junkie
Messages
177
Reaction score
524
Points
132
Location
North Platte, Nebraska
Boat Make
Yamaha
Year
2003
Boat Model
LX
Boat Length
21
So when I pulled my under warranty SBT engine (installed by the previous owners shop) on my new to me 2005 AR210 two stroke I figured I had better check the feel of the carrier and jet pump bearings while I had the motor out. Naturally something in the bearings did not feel right turning it by hand so I pulled the carrier bearings to find that the driveshaft is misaligned, off-center, and in a bind.
20220723_214456.jpg
I plan on cleaning up the corrosion between the jet pump parts and reassembling it to see if the driveshaft is more centered when I am done. If cleaning the corrosion between parts dose not center up the driveshaft properly am I correct in thinking the jet pump transom plate needs to be re shimmed at the mounting bolts like it is now just with the driveshaft centered when I am done?
20220724_140631.jpg


Second question...
In the center of my carrier bearing coupler there is a loose rivet that seems to be a path for water to enter the boat by following the driveshaft splines (there were no O-rings in the carrier bearing coupler to seal the driveshaft splines as the parts diagram shows) and threw the rivet hole. I don't see any other couplers online with a rivet hole in them when I search the part number is this something someone added at some time for some reason? there also seems to be cracks radiation out from the hole that don't look right. Should I buy a new coupler? Thanks for all the help in advance
20220724_140521.jpg
20220724_141651.jpg
 

Hoppy

Jet Boat Junkie
Messages
177
Reaction score
524
Points
132
Location
North Platte, Nebraska
Boat Make
Yamaha
Year
2003
Boat Model
LX
Boat Length
21
I will answer my own driveline questions and ask more... Cleaning up the jet pump parts did nothing for me on the driveshaft misalignment I ended up pulling the transom plate to find two problems. #1 the ride shoe did not sit flush with the transom and caused the transom plate to sit at a funny angle, I used angle grinder to level out the ride shoe with the transom it would have taken a lot of shims to align the plate without removing the high spot. (pics show where the ride shoe sat high and missing paint on ride shoe shows where I had to grind on it.

20220729_213845.jpg

20220729_213823.jpg

So after getting the transom plate to sit flat on the transom I ran in to problem #2 the driveshaft sat too high to line up with the midshaft bearing and any attempt to shim the transom plate to move the driveshaft down put the caused the pump to interfere with the pump mounting brace that sits above it. So I started looking hard at the pump on the starboard side and got to noticing the transom plate on the starboard side sits flush on the bottom with the ride shoe and the port side I am working on sits about 0.090" higher on the transom (see pit)
20220731_081148.jpg

To fix I got the file out and slotted the mounting holes for the transom plate carefully filing each one down .090" the amount I measured it being higher then the other side. Once I got the transom plate flat on the transom and mounted at the same height as the one one the other side I was able to reinstall my pump and check the alinement of the driveshaft and found it was now centered in the midshaft mounting bracket hole. Now with the driveshaft centered in the hole all I had to do was verify the midshaft bearing sat square with the driveshaft and would bolt down without putting the driveshaft in a bind. I accomplished this by reassembling the midshaft bearing and sliding it on the driveshaft spines towards the mounting wall (without the sealing hose installed to prevent the hose from affecting the angle) and shimming between the bearing and wall so that all three mounting ears touched the wall at the same time. (see pic)

20220730_144414.jpg

once I got the pump mounted flat, the right height and the midshaft bearing shimmed I verified the pump sat the same trim angle? as the other side and made sure the pump was not twisted on the transom by making sure the steering nozzle bolt holes were at the same angle as the other side. (see pic)

20220730_144006.jpg

20220730_143856.jpg

as with all alignments I took some more tweaking and shimming to get everything perfect so the driveline was not in a bind but the in essence the goal is to get the driveshaft centered in the midshaft bearing hole an then square the midshaft bearing to the driveshaft. There is a tool for this but I made due without. I will link an example of the tool with instructions
Pump Alignment Tool - Torrent Pumps. Once I was happy with the pump alignment l marked on the transom with a sharpie where the transom plate need to be mounted with my now slotted mounting holes I wanted to be sure I put it back in the same place when I reinstall it with 3m 4200. I also used some J-B weld to fill in the transom bolt holes so they are no longer slotted.

Answer to my second question apparently there was a factory rivet installed in the coupler for some reason the good used oem bearing assembly has one in it.


20220803_024347.jpg

With every thing if found wrong with the driveling alignment I can only assume it was that way when the boat was built and that is why the bearings in the pump and midshaft bearing are needing replaced.
 

Hoppy

Jet Boat Junkie
Messages
177
Reaction score
524
Points
132
Location
North Platte, Nebraska
Boat Make
Yamaha
Year
2003
Boat Model
LX
Boat Length
21
Now for the next question... the driveshaft splines have some rust and pitting on them from the sealing o-rings in the midshaft bearing missing (see pic), no grease on the splines, and probably from the misalignment of the pump and midshaft bearing20220803_040029.jpg

Do you think I should replace the driveshaft? or should I just replace the pump bearings and seals and reuse the driveshaft? I'm concerned with the rust pitting it may brake. Has anyone used a shaft like this or should I just spend the $350 for a new one. 20220803_024327.jpg20220803_024320.jpg
 

84rzv500r

Jetboaters Captain
Messages
1,127
Reaction score
1,888
Points
222
Location
Lower Keys MM29
Boat Make
Yamaha
Year
2004
Boat Model
AR
Boat Length
20
its not uncommon for the three through hull bolts on the base plate for the midbearing housing to loosen up over time and go out of alignment and take out the mid bearing and take on water... I've also had engine mount's fail and take out the mid bearings, I've also had shaft splines corrode and strip... as well as sheared the shafts shear off just aft of the two o-rings...
 

Julian

Jetboaters Fleet Admiral 2*
Staff member
Administrator
Messages
18,368
Reaction score
20,455
Points
1,082
Location
Raleigh, NC 27614
Boat Make
Yamaha
Year
2016
Boat Model
242X E-Series
Boat Length
24

Hoppy

Jet Boat Junkie
Messages
177
Reaction score
524
Points
132
Location
North Platte, Nebraska
Boat Make
Yamaha
Year
2003
Boat Model
LX
Boat Length
21
its not uncommon for the three through hull bolts on the base plate for the midbearing housing to loosen up over time and go out of alignment and take out the mid bearing and take on water... I've also had engine mount's fail and take out the mid bearings, I've also had shaft splines corrode and strip... as well as sheared the shafts shear off just aft of the two o-rings...
Thanks for the information on possible failure points, that all makes sense. Is shearing the drive shaft off very common? I have read in some of your posts that you had sheard one off 84rzv500r
 

Hoppy

Jet Boat Junkie
Messages
177
Reaction score
524
Points
132
Location
North Platte, Nebraska
Boat Make
Yamaha
Year
2003
Boat Model
LX
Boat Length
21
How much is the coupler? That is what might get shredded if the spline fails....

I'd probably use the shaft as is....but each to their own.
I'm not sure on the price of the coupler without looking. Surprisingly with the driveshaft looking like that the coupler splines looked fine. I bought a parts boat (I can't help myself) hopefully it has couple of good driveshafts, I have not had the chance to pull the pumps.
 

84rzv500r

Jetboaters Captain
Messages
1,127
Reaction score
1,888
Points
222
Location
Lower Keys MM29
Boat Make
Yamaha
Year
2004
Boat Model
AR
Boat Length
20
Thanks for the information on possible failure points, that all makes sense. Is shearing the drive shaft off very common? I have read in some of your posts that you had sheard one off 84rzv500r
stock shafts usually the splines corrode and start slipping in the coupler ive had 2 incidents of this ... SBT stainless shafts twist of if you dont get off the throttle when you have the boat out of the water and it comes back down... at WOT with an empty pump... i have had 2 instances of this...
 
Top