Axis Wakeboard Boat Forum

The lake I just started going to has a long cruise through a no wake section before I can get up on plane. I overheated the other day and ate an impeller. Luckily I had a spare and ran fine the rest of the day. Next time out I payed more attention. It seems that I do not start flowing water into the system until the boat gets up on plane and forces it into the pump. After that the pump is primed and I have no issues until I pull it out of the water again. I have checked everything that I can think of:

-Impeller is in good shape and cover is tight with no leaks.
-No debris in the intake system. I removed all of the hoses from the system and fluhsed water both ways through the V-Drive unit. All flow well.
-I have the inline engine flush unit (Perko flush pro). I blew through it and it took almost no effort to open. I would think the pressure of the water on the hull would have no problem opening this valve.
-The flush valve is clear and I can watch the water flow through it. Nothing at initial idle until the boat fully planes at around 15-18 mph. After that the system remains primed and temps were 150-170 all day.

Any ideas? Thanks!

"-I have the inline engine flush unit (Perko flush pro). I blew through it and it took almost no effort to open. I would think the pressure of the water on the hull would have no problem opening this valve."
Any chance you're sucking air through the Perko until water gets pushed in? Or perhaps an air leak somewhere in the line?

Thats what I thought but I can not find one. When I pulled the hoses to inspect them the hose between the pump and perko flush pro was still full of water after bring out of the lake for a day. I would assume that part was still primed. It was dry south of the flush valve as you would expect from sitting on the trailer. After blowing into the valve and seeing how easy it opens I find it hard to believe just the pressure from the boat sitting in the water wont open it.

Found the problem! There are plastic inserts threaded into the in and out sides of the raw water pump. No idea how this happened but the one in the outlet of the pump backed out and was sideways in the hose between the raw water pump and transmission cooler. Anyone know what purpose these inserts serve?

can you post a pic?