2008 RXT 215 supercharger blown & coolant escaped - Do i need to pull the engine?

[only1battman]

I just had my 2008 RXT 215 with 200hrs out on the bay this weekend. heard some grumbling coming from the back end while out on the bay. Took the seats off and tried to listen. still seemed to run fine, power as normal still could go full speed. So i originally thought it was a bad jet pump bearing. Decided to not ride anymore and left it tied up to boat, at the end of the day was going to limp it back to the marina, but it only made it about a 1/4 mile before clanging a few times and dying. Had to tow it back. we towed it back slow and got it up on the trailer. Once out of the water i pulled the drain plugs and found coolant came out. it appears quite a bit of coolant came out. Yesterday i pulled some hoses and the jet pump to try and figure out what happened and found that there was a bunch of white powdery substance in the intake tubes and on the in and out side of the supercharger. also figured out that the supercharger ate itself and the wheel is now loose.

Supercharger was rebuilt at 173hrs with SS washers.

So my questions are,
1) what are the next steps? Anything specific i need to look for?
2) do i need to pull the engine again? Already pulled it once to replace output shaft and broken motor mounts (really don't want to).
3) from some of the reading that i have done. it appears i should be OK and not have to pull the engine as long as no large chunks are missing. Replace Oil, replace S/C?
4) I assume somehow it burnt the coolant causing the powdery in the intake, but the plugs looked OK (see pics). and there was still quite a bit in the hull.

 

[ski-d00]

1. pull supercharger, post pics
2. probably won't need to pull engine unless sc grenaded
3. don't know yet, refer to #1
4. that isn't burnt coolant, it's aluminum dust from your sc impeller touching off on the housing. you will probably need a complete new sc and not just rebuild. your bearings went out of your sc and good chance there are pieces down in the pto housing but let's not get ahead of ourselves. back to #1

 

[only1battman]

Sorry for the late response. Supercharger blew two days before we went on vacation. Got back and pulled the S/C. it definitely appears to have a failed bearing and warbled the wheel into the housing. when pulling it i noticed that the top bolt was slightly loose and figured out why once pulled the S/C away. a small chunk of the PTO housing appears to have broken off. So sadly ill need to pull the engine anyway as it will be near impossible (or actually impossible) to pull the PTO cover in the hull. it also appears that this answers the coolant loss part of my questions and probably rules out coolant actually getting into the engine.

 

[ski-d00]

I'd pull motor as well. How about posting a pic of the end of the sc to see if anything broke apart and went into the motor?

 

[only1battman]

Oh right, forgot to take pictures of that side. everything looks intact, but the pinion gear does look discolored slightly. Im wondering if it got hot when the bearing went?

My garage will be finished in the next week or so, so im going to hold off on pulling the motor at the moment until i can do that on a flat dry surface. once i pull the motor and pull the cover off ill send pictures of that area.

At this point are we thinking its just going to be a replacement of the PTO cover and not the entire engine?

 

[ski-d00]

I think your motor will be fine. I would buy a used supercharger to use the housing and the wheel. Buy a sc rebuild kit, used pto housing (make sure to get newer style with 7 o'clock CPS). Pull motor, remove pto housing and front oil pump housing checking closely for leftover ceramic washers. Let us know what you find and post some pics.

 

[only1battman]

OK great! Thanks for backing up what i thought (and was hoping for). I already have a new to me supercharger, S/C rebuild kit and oil change kit. Looking for a PTO cover now.

The supercharger that blew up was one that i rebuilt with SS washers so hopefully that shouldn't be an issue.

As for the PTO cover, Partzilla lists the P/N as 420812623. this ebay link should be the correct PTO cover. assuming that CPS is the crank position sensor is this the newer design? its a little unclear from angle of the pictures.

 

[ski-d00]

Yes, that's the correct pto housing. Anything 2007 and newer will work.

 

[only1battman]

Sorry for the long delay but finally got around to getting the correct parts and pulling the engine and getting an oil sample tested.
Oil sample came back with only really slightly high aluminum levels, which is good, and what I expected to see. as you can see from the close-up. the oil still looks really good only about 20 hours on the oil and not even really loaded with aluminum. there were some chunks of aluminum that i was able to flush out.

Now is the "easy" part. put engine back in and get everything hooked back up. done this part before so no issue here.

Thanks for the help everyone!