Copy pasting this from the help thread I just started on thehulltruth because I don’t feel like making a condensed version for nyspeed.
I have a 2000 Chaparral 180 SSe with a VP SX 3.0. A week ago we were out for most of the day with a pretty heavy load (6 adults, 1 kid) and had no issues. Tonight we went out with a light load (3 adults 2 small kids) and had a bit of a scare. After launching the boat we were about 3 miles down river and decided to stop and get some drinks out of the cooler. I noticed the carpet was wet along the floor at the rear bench seat and immediately started looking for where it came from. Finding nothing spilled I popped open the sunpad and was staring at water up to the floor.
I immediately hit the bilge pump and fired up the engine. After a very quick look to make sure a cooling hose hadn’t blown off causing the engine to be pumping water into the boat we made WOT run to a boat launch less than a 1/2 mile away. I figured worst case I would beach it on the ramp. Safe at the dock with the engine off I watched and the bilge was gaining on it. After about 15 minutes the water was down to where the pump was sucking air. By this time I had arranged a car ride with another boater back to my truck/trailer since I wasn’t comfortable risking making the run 3 miles back upriver. I gave the wife instructions to watch the water level and if it got past the bilge pump to kick the pump back on. In the 20 minutes or so it took me to get back the water level did not seem to rise.
Towing it home I’m thinking it had to be a blown hose, freeze plug or something that was letting the raw water cooling just pump water into the boat. When I got home I unscrewed the drain bolt and got the remaining water out. I then hooked the outdrive up to the garden hose with some muffs and fired the boat up. First at idle, looking everywhere for leaks, then at 3k RPM when I couldn’t find any. Even at 3k still no leaks found. Water was pouring out the prop and the upper hose at the front of the engine was clearly pressurize when I was squeezing it.
That being eliminated I then put the garden hose in the boat and proceeded to fill it back up nearly to the floor. Looking under the boat the only leak I found was a very slow drip from the transducer. About one drip every 10 seconds, so I don’t think there is anyway that could have nearly filled the boat. Besides that if that was the source of so much water it still would have been coming in as the boat sat at the dock waiting for me to get the trailer. I did stand on my head and try moving the transducer from inside the engine compartment to see if maybe it was loose but it seemed secure.
The only thing I’m not 100% sure of is how much water was in the boat when we left. It’s stored in my garage (and yes, I actually looked around the ceiling for leaks). I did pop open the swim pad to check the gas level and I think I would have noticed that much water but I didn’t specifically look like I normally do. When launching the boat I did have to back in a bit farther than normal, but I was launching from the farthest end of the boat docks where I don’t normally launch and just chalked it up to the end ramp being shallower. The boat didn’t pop right out of the water but the 3 adults were in the back, the gas tank was just topped off, and with just two 50lb kids in the bow the time to plane wasn’t enough to make me concerned. It certainly planed a LOT FASTER than when I noticed the water and made the run for the boat ramp. In that case I went full throttle and actually moved up into the bow until it planed since the boat was taking much longer than normal to plane.
At this point I’m probably going to just drop it off at the shop and have them look at it, but figured I’d post here and see if I got any good suggestions. I’m wondering if maybe it’s a seal on the drive that’s only leaking bad when the drive is trimmed all the way down. That would explain why it wasn’t leaking bad once I got to the dock, since I had already trimmed it back up in preparation for needing to beach it. Seems unlikely though. Maybe before I drop it at the shop I’ll pop it in the water quick and see if I can spot the water coming in with the bilge dry.