[LeeMonster]

I got this wave runner a couple years ago and have not been able to get it to run right... yet! This is my first ski and admittedly, I'm not a motorhead.

Engine turns over and seems to run good, but on the water I can only get it to about 11-12 Mph full throttle. If I run it for a while and shift my weight forward it can eventually plain out and I can increase speed to 22-25Mph and hold it there until I crash a wave or turn too sharp. However, I read this can do 30-35mph top speed.

Gas is good, getting spark on both plugs, carb seems clean, but have not taken it apart to inspect thoroughly. Prop seems a little worn and dinged and there is some gap. See attached pics.

Before replacing the prop, is there any other things I should check that would be cheaper and easier to fix? Can the prop be adjusted to fit the gap better?

 

[wmazz]

Reseal the grate to front of the pump (Intake Gullet). It is a source for major cavitation
if not sealed.

Bill M.

 

[LeeMonster]

Reseal the grate to front of the pump (Intake Gullet). It is a source for major cavitation
if not sealed.

Bill M.

Thanks Bill. I will check that out. Would a basic marine silicone do the trick or is there something special I should use?

 

[wmazz]

A low shrink clear is good enough. Let it set up overnight before you give it a try.

The grate is the common leak, but the sides of the pump gullet can leak too.


Bill M.

 

[LeeMonster]

A low shrink clear is good enough. Let it set up overnight before you give it a try.

The grate is the common leak, but the sides of the pump gullet can leak too.


Bill M.

The intake grate was not sealed well and one bolt head was sheared. There was sand on the top side of the grate so I know it was leaking into it.

Instead of silicon, would a butyl rubber tape work better?

Also, based on the pics, do you think the gap is OK between the impeller and the metal housing? Is this what you referred to as the gullet?

 

[leemonster69]

Intake grate sealed. Carb tuned as best I can. Still, no top end. Good acceleration up to 1/3 throttled, then no acceleration from 1/3 to wot.

Could this a clogged carb or is it the prop?

 

[leemonster69]

And compression in both cylinders is 110 psi.

 

[wmazz]

The intake grate was not sealed well and one bolt head was sheared. There was sand on the top side of the grate so I know it was leaking into it.
Instead of silicon, would a butyl rubber tape work better?

I prefer being able to lay a wide bead, bolt it down, and spray
the silicone with wd-40 for a clean removal, and let it dry for
24 hrs.

Using that method I know the gaps are filled.

Also, based on the pics, do you think the gap is OK between the impeller and the metal housing? Is this what you referred to as the gullet?

It is not good.

Bill M.

 

[wmazz]

Intake grate sealed. Carb tuned as best I can. Still, no top end. Good acceleration up to 1/3 throttled, then no acceleration from 1/3 to wot.

Could this a clogged carb or is it the prop?

The 500 will accelerate up to 3/4 to 7/8's throttle. If it was the engine,
I think you would know because the engine would cut out.

Most likely the pump and impeller. Rock damage like dings in the
leading edge of the impeller, or a bent impeller blade are common.
But so is impeller wear like in LeeMonster's post and rock damage
to the pump vanes.

When you sealed the grate, did you also seal the ride plate?
Sealing the ride plate often causes problems.

Bill M.

 

[leemonster69]

The 500 will accelerate up to 3/4 to 7/8's throttle. If it was the engine,
I think you would know because the engine would cut out.

Most likely the pump and impeller. Rock damage like dings in the
leading edge of the impeller, or a bent impeller blade are common.
But so is impeller wear like in LeeMonster's post and rock damage
to the pump vanes.

When you sealed the grate, did you also seal the ride plate?
Sealing the ride plate often causes problems.

Bill M.

Thanks Bill,

I did not seal the ride plate, just the intake grate.

I pulled the jet pump assembly out last night. Waiting on my shaft key so I can remove the prop. I think I'll be shopping for a new prop.

 

[Lake Lab]

I have similar issue with 2006 VX110 Deluxe. won't attain speed of more than about 8 mph. is there any YouTube video on how to apply the seal?