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nzjetboating.com Forums => Jet Units & Driveline => Tech Library => Steering Systems & nozzels => Topic started by: churchward on February 16, 2010, 18:55:35 PM

Title: nozzel size?
Post by: churchward on February 16, 2010, 18:55:35 PM
does any one hve an idea what size nozzel i should run on a 14ft aluminion with 2stage colorado and holden v6?? thanks matt
Title: Re: nozzel size?
Post by: CBBR on February 16, 2010, 23:46:11 PM
do you have a rev counter? you want to "choke" it [the nozzle] till you get the right revs Holdon V6 what?
Title: Re: nozzel size?
Post by: JR on February 17, 2010, 09:53:50 AM
does any one hve an idea what size nozzel i should run on a 14ft aluminion with 2stage colorado and holden v6?? thanks matt
Could be anywhere from 95mm to 105.. you will have to try get you rpm rite.. aAe aAe To big will give you good hole shot and no top speed, >>@ >>@ To small will give bad hole shot and good top speed... >>@ >>@ But there is a fine line.. pig pig Hope that helps... OoOoO Cheers JR
Title: Re: nozzel size?
Post by: Nigel on February 17, 2010, 11:50:57 AM
to big will cause slippage to unit not presureising as well
Title: Re: nozzel size?
Post by: churchward on February 17, 2010, 15:12:59 PM
thanks for your advice, its a 1996 ,3.8 vs motor, the one on at the moment is 111mm?? is that the right mesurement?-i mesured the inside of the nozzel.
i had to wind in the throttle stop couse it was hitting the rev limiter when booted?? so thats when i thought that the nozzel is to big, what revs should it go to and at which point do i gauge it, ie from standstill and booting it or going flat out across the water?? thanks matt
Title: Re: nozzel size?
Post by: Karl on February 17, 2010, 16:28:27 PM
Are your impellors in good condition? They will slip if the clearance between the OD of the blade and the wear ring is too great. Idealy run about 0.5mm.

Has it always slipped or is this a recent thing??
Title: Re: nozzel size?
Post by: churchward on February 17, 2010, 19:32:37 PM
the impellers are all good, jst been redone buy Hamilton. we have jst redone the boat so really jst trying to get set up right. but we must have got the wrong advice for nozzle size! Ive got hold off another one , so will try that with more success hopfully!
Title: Re: nozzel size?
Post by: CBBR on February 17, 2010, 19:52:54 PM
my HJ752 has a 100mm nozzle, 3.8VN, seams to go ok.
Title: Re: nozzel size?
Post by: FLM on March 01, 2010, 19:50:52 PM
I have a 141a running a vn 3.8 and 772 with standard 19 degree blades. It has a 95mm nozzle and pulls 4500 - 4600 rpm. Tried a 97mm one once but handling suffered became less responsive.