2000 21v Transmission Help

[cse80]

I have milky transmission fluid and am not sure where to go from here. How I got to this point is a long story, but I'll try to keep it brief. Family took the boat out; I started on slalom w/ my wife driving.

1. The boat reaction was delayed on takeoff. She would give throttle and it would take a sec before it responded. I took over and noticed the same thing (tranny slipping?). I shut down the skiing for the day and drove over to the sandbar near our house for a couple hours.
2. Driving home the boat wasn't maintaining speed. I thought the throttle lever was just not holding speed like it sometimes does. I gave it some throttle and it didn't respond. I threw it in neutral and opened the rear hatch. Full of water and my bilge didn't kick on. The water wasn't quite high enough to spill into the side lockers or out the front under the flip-up seat, but there were definitely things getting wet that shouldn't. We shut down the boat, turned on the bilge and started bailing. Realized that no more water was coming in. Got a tow to the dock, put it on the lift, hooked it to the hose and cranked it. Water spraying everywhere in the engine compartment. Realized it was just a split intake hose. Replaced hose and in the process found a ton of impeller pieces. Changed my impeller only to find it was intact. I've had the boat 3 years and never had a busted one so no telling how long that crap has been in there. Boat fired right up w/ no leaks.
3. Next weekend we put the boat in the water for a little test run. Fired right up again, but when I gave it throttle there was no movement (seems to be related to original problem, but maybe not).
4. Put it back on the lift...and it wouldn't crank. Did some detective work and narrowed it down to the starter. It would have definitely been in water when the engine compartment filled. Replaced the starter and now it fires back up.

After firing back up, still can't get a proper throttle/tranny response. Problems 2 and 4 are fixed. 1 and 3, whether separate, related, or the same thing are not. Engine oil is fine, v-drive oil is fine, tranny fluid is low and really milky. I'm definitely a novice and not sure how/where water can enter the tranny. It makes sense, with so much water being in there, that some may get in. But, there was already some issue with tranny/throttle response prior to the water intrusion. Do I drain and refill the tranny fluid a few times to see if I can get all the water out? Is this an automatic need a new tranny situation? Any thoughts/suggestions on what to check/how to proceed are appreciated.

[Grebva3]

Absolutely drain and refill both. Need to find out how water is getting into the vdrive could have a bad o-ring that’s allowing water into the vdrive

[freeheel4life]

There's a breather on the trans. Sounds like the water got high enough to drink that water in. The washed out fluid may have killed the clutch packs.

Flush the fluid and make sure its topped up. If it stays red after trying to run for a while and it still slops its time for a refurbished 71c or rebuild it yourself. If you run it for a while after and you get the milkshake out your trans cooler is cracked

[cse80]

Appreciate the advice. I will be working on it this week. Hoping for the easy route.