Pump question

[jdeaton]

My project 1986 Liberator has an Aggressor pump that really hooks the boat up.  I am going to do a overhaul this winter, while the motor is out of the boat, and The trailer is being painted.  How do I know which impeller I have in my pump, is it marked, or is there something I measure (vane angle, vane length) to figure the "cut"  I have the chart from different pump manufactures telling me the impeller I need for horsepower and RPM range, I'll have those numbers after I dyno the motor this winter, I just don't know what I have in my current setup. 

 

[SlowRyd]

here ya go
http://www.arsmarine.com/Pump_Parts/impeller_chart.htm

 

[jdeaton]

Thanks, Ive been on the ARS website for hours today and never saw that chart.

 

[hellnback]

yeah impellor ?'s confuse me too  mine has "J250A" stamped on it what does that mean?  it's in a berkley 12 JF pump with inducer.

 

[KONA77]

this is just a wild guess but might mean it's an "A" impeller

 

[hellnback]

thats what I figure as well just wondering if the 250 means 25 degree cut

 

[CorDog009]

Usually an A impeller is pretty big unless you have alot of hp to throw at it. My old BBC with almost 500hp would only spin an A to 5000 at about 69mph. My new boat has almost 1000hp on a 300 shot and runs a stainless steel B with inducer, turning it over 6000rpm. The guy who bought my last boat swapped to a B and picked up 1000 rpm and 10mph with no other changes.

 

[jdeaton]

Does an inducer and/or a stuffer effect the size (or cut) of the impeller?

 

[J C Gordon]

An inducer loads the pump harder so yes it will feel like a larger impeller and pull the Rpms back a lil but not bad. 

 

[jetboatperformance]

My project 1986 Liberator has an Aggressor pump that really hooks the boat up.  I am going to do a overhaul this winter, while the motor is out of the boat, and The trailer is being painted.  How do I know which impeller I have in my pump, is it marked, or is there something I measure (vane angle, vane length) to figure the "cut"  I have the chart from different pump manufactures telling me the impeller I need for horsepower and RPM range, I'll have those numbers after I dyno the motor this winter, I just don't know what I have in my current setup.

We sell AT/Dom pretty exclusivley now but were an Aggressor dealer for several years , Aggressor  Impeller cuts and how those Impellers react varies slightly from  the rest (Berkely Dominator A/T etc) An Aggressor "A" cut acts more like a Berk AA and so forth The stamping on the back of the impeller may be a good indicator but the true test will be actual inspection and blade angle measurements Call if we can help Tom

 

[jdeaton]

I will have questions, so when I disassemble the pump, I'll probably give you a call.

 

[badblood]

Did not see anything on what size motor or how many rpms.  I am running an aggressor AA+ and like the large impeller, but it requires a strong motor. Do you use nitrous on the motor, what do you want the boat to run? If you have any questions feel free to PM me.
Keith