need help fast.........

[topkicktech]

i have a 05 3d rfi. runs great but if i get on the throttle hard it starts to cavitate and doesnt have much thrust. seams as tho something is slipping or its pulling air into the pump. please help asap need it running for sunday.

 

[1MACGYVER]

You have checked there is nothing on/around the intake grate and/or tunnel?
If its stock id recommend getting the upgrade solas stainless prop and an intake grate.
I fitted a R&D 97 XP grate (most of them dont list a 3d but the XP ones fit)

 

[topkicktech]

everything is clear of the grate and the impellar. its like the impellar is slipping or its sucking air form somewhere.

 

[1MACGYVER]

can you see the gap between the prop and the wear ring? it should be less than 1mm, much more than that will cavitate and lose power.

 

[topkicktech]

so i tore the pump apart. the wear ring does have some gap. nothing that i would think would cause this much power loss. i removed the drive shaft. the carbon ring is about 1/4" bigger then the drive shaft. is there suppose to be some other seal in there? could i be sucking air thru the hull?

 

[1MACGYVER]

theres also 2 o-rings in there but i dont know of the gap.
if that was your problem there would be a lot of water entering the hull through that seal when sitting in the water not running.