Changed impeller - still 43mph and now error P0326


I have two 2007 GTXs with 90 and 105 hours. Bought used and put few hours on each. YM (hull number) went 52mph. YK May have gone 52, remember 42mph then 30mph with slipping acceleration. Changed wear ring and impeller to Solas 11/19. (Thanks Joe Z.!)

YK after now only goes 42 mph and on first acceleration popped alarm and code P0326. Knock sensor?

YM was going 52mph then 30mph and suddenly full reverse when accelerating. Turned out top two bolts on the Venturi sheared off! Thrust shot up and over forcing reverse shroud down by itself!

Gonna fix YM by putting YK repaired pump assembly with Solas impeller onto YM. Is this bad idea?

Going to rebuild YM pump since drive shaft impeller factory seal was crimped when mounted (looks like mud inside. Will use Solas 11/19 again.

Both running on marina gas. Should I replace YK knock sensor? Or is it something else?

Is it a bad idea to take YK’s Solas impeller pump and get YM up and running (hopefully 52 again)?


Glad to help!

These are both 155s, correct?

And yes that code is a knock sensor; likely faulty.


Yes, both 155s


Change the knock sensor and see if that helps. It’ll pull timing if it thinks it is knocking. Older plugs?


Thank you.

I don’t have enough records to know how old the plugs are. I’m putting new plugs in both.

Any idea why 43mph is top end?

Thank you


What RPMs are you reaching @ 43mph?


7500 (sorry, I don’t see notifications fast enough :frowning:


Post up once you’ve done the plugs and knock sensor


Thanks, Joe

I can’t get to the knock sensor until Columbus weekend -worst case in the Spring. I will get plugs on both skis done and switch pumps to rule that out.


So I did not get the knock sensor replaced yet. It will have to be Spring on that. In the meantime, a coupla odd things on the slow jetski YK(43mph). My alternate theory was the OPAS sticking out incorrectly.

The elbow filter on the Venturi is in the correct 20deg angle and when I removed it I see the screen is probably about 60% clogged. I’m going to replace it.

It gets better. I learned a lot rebuilding the other pump on YM jetski. Like how the Venturi should be bolted onto the pump. When I inspected the 43mph YK pump trying to asses the OPAS filter, I found the top half of the Venturi was separated about 1/2” from the pump. The top two bolts holding the Venturi were reversed - rather than brass nuts on the pump housing someone rebuilt it with bolts facing back to the Venturi. The nuts were stopped against the bolt shoulder since he bolt head pulled thru the pump housing when tightened.

I really really think this gap and the very likely OPAS not working at speed is causing the 43mph speed.

Welcome your thoughts on how well this may do the trick or if I’m barking up the wrong tree.