Last night we were idling for a while just enjoying the water, and I noticed the temp guage started climbing. I gave it some throttle and it quickly dropped back to normal. It was getting late so we decided to head straight back to the launch just in case, instead of heading the rest of the way around Grand Island.
Tonight I pull the water pump impeller, expecting to see some wear, only to find this:
The boat is a 2000 Chaparral, purchased new from Collins Marine. They have replaced the impeller once, 2 years ago.
Is it just me, or does that look like a completely fucked up casting of that impeller housing? I don’t see how having those rubber impeller vanes wedged in there like that can be the correct design.
I’ll be taking it to Collins tomorrow on lunch, but thought I’d post it up here because at this point I’m clearly a bit confused.
The thing I really don’t get is if this was cast incorrectly, how the hell did the service guys at Collins not catch it when they replaced the impeller? You literally have to pry the damn thing out, and wedge it back in there.
EDIT: In case it’s not clear, the first picture is with the impeller removed and sitting on TOP of the casing.
it squeezes the water out of the vanes, otherwise there wouldn’t be any pump action, that water would just spin with the impeller w/o moving on or out of the housing
I work at wheelhouse marine we rebuild those things all the time allthough Ive seen them in much worse conditon than that, the way we test em is out of the water, hooked up to the hose, if it dosnt pump out water we pull em apart. you could go to collins but Im pretty sure wheelhouse will be cheaper if it does need work. goodluck
that impeller looks fine, you are either losing suction on the intake side or the bellows are plugged. Another possibility but unlikely is the water pump being bad.
FYI using a garden hose to trouble shoot this is not recommended because of the fact that it is pressurized. Also If you do for whatever reason hook a hose to the boat to run it only run it at idle, I have seen many times guys revving the engine and actually sucking the hose dry and collapsing it.
Go to big lots buy a 55 gallon tote for $15 and use that to run your boat in the driveway, I can tell by the housing and impeller that you have a Volvo Penta out drive, more then likely an SX. If this is the case then the tote will work perfect for you.
Thanks for the advice about the tote. There is actually one sitting on the side of my house no longer in use, since Amherst just switched us over to their new anti-rat totes.
I’m pretty sure what ever problem I had took care of itself. When the temp originally started climbing we were about 1/2 way between the north and south end of Grand Island, on the west river. The original plan was to continue north, loop around the island just below the north GI bridge, and head back up the east river to Niawanda where we launched.
After the overheating I decided it would be safer to head south, and head back to the launch down the west river after circling GI at the Beaver Island State Park end. It was just as far, if not farther, but with two safety advantages. One, you’re not going toward the falls should something fail. Not sure how many of you have ever gone around the north tip of GI in a boat, but it’s uncomfortably close to the falls if you’re not 100% confident in your craft. Two, there is a lot more traffic on the east river, so if we broke down there it would be much more likely to have someone offer to tow us in. And once we made it around GI, we’d be going with the current, so worst case we could crack open a couple beers and wait for mother nature to bring us back to Niawanda.
All that said, the boat ran perfect for the several miles on the way home. Once we were near the launch I even slowed down to idle to see if the problem happened again, and it didn’t. So chances are it simply sucked in some of the heavy green moss that there was a lot of floating around, and when I gave it some throttle the extra water pressure pushed it out. Or some was stuck against the intake screen, and when I shut down to inspect that it fell off due to the pump not being running. By the time I tilted the drive up to check it the obstruction may have fallen off.
Regardless, the impeller is 2 years old, so a new one will go in today. Since I had to pry both hoses off the pump I’m going to attach my flusher to the drive and just push some water through and see if crap comes out. I’ll probably pull the upper hose and do the same there.
Mostly this whole thread was me simply not knowing that an impeller is wedged into the housing that tight.
Good deal, not a bad idea to have a spare on the boat as well as the tools to replace.
Details on the boat?? size motor ??
I have a 02 Glastron SX175 with the 3.0 tops out at 40 mph. We have a blast tubing and such. I love taking people around the north end of the river and seeing the look on their faces when I explain to them that the mist they see is from Niagara Falls.
18’ Chaparral 180SSe. Same 3.0, but after upgrading to an SS prop (and experimenting with a few different ones) it will top out between 45-48 depending on conditions.
Spend a lot of time wakeboarding. Installed a pylon a couple years ago, and plan on installing a tower soon.
And yeah, when you tell people the mist they see is the falls they usually get a little nervous. Between that and the “Dangerous Water Ahead” sign on Navy Island.
