SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: barracudajet on July 18, 2015, 10:20:07 AM

Title: Top speed.
Post by: barracudajet on July 18, 2015, 10:20:07 AM

I have a 2000 21ft ultra with a marine power 330hp 454 barracuda jet with new Berkley A impeller, drop snout, ride plate andplace diverter. It has a modified grate that lets in large rocks. It tops out at about 46 mph at around 4800 rpm when its running. Is this a sign of low hp from my engine.

Title: Re: Top speed.
Post by: Flusher on July 18, 2015, 10:33:15 AM

Quote from: barracudajet on July 18, 2015, 10:20:07 AM

It has a modified grate that lets in large rocks.

Does this imply that the impeller and bowl might be damaged from rock ingestion?

Damage to vanes of the impeller and bowl greatly reduce pump efficiency resulting in lost thrust.

Please post a picture, looking into the suction housing at the impeller.

Title: Re: Top speed.
Post by: barracudajet on July 18, 2015, 10:50:59 AM

I did suck up some rocks by big bend in Laughlin. It destroyed the impeller. I bought a Berkley rebuild kit and installed the new impeller but not the wear ring because it fit so tight I didn't think the new one could be any better. Also it looked good and smooth with no scrapes. I just pressed on the new bearing and used the parts that would fit my barracuda jet. Is runs the same speed as before the rock damage. The bowl didn't have any visable damage. Is this slower than I should expect. Having more people in the boat makes very little difference.

Title: Re: Top speed.
Post by: Your Mom on July 18, 2015, 10:57:05 AM

I'd say with a 21 ultra an under 350 hp... Your about right for speed.

Title: Re: Top speed.
Post by: Riverrat81 on July 18, 2015, 11:03:26 AM

I have a 1995  20 1/2 ft advantage open bow classic. 454 American turbine pump ss a cut impeller with ride plate and diverter . I run identical speed at the same rpm 46-48 mph @ 4400-4600 rpm and I doesn't really matter how many people are in the boat .


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Title: Re: Top speed.
Post by: GT Jets on July 18, 2015, 11:23:20 AM

Quote from: Riverrat81 on July 18, 2015, 11:03:26 AM

I have a 1995  20 1/2 ft advantage open bow classic. 454 American turbine pump ss a cut impeller with ride plate and diverter . I run identical speed at the same rpm 46-48 mph @ 4400-4600 rpm and I doesn't really matter how many people are in the boat .


Sent from my iPhone using SoCal Jet Boats

Sounds about right...

Is there a question hidden in there?   ???

GT

Title: Re: Top speed.
Post by: Riverrat81 on July 18, 2015, 11:25:13 AM

Quote from: GT Jets on July 18, 2015, 11:23:20 AM

Sounds about right...

Is there a question hidden in there?   ???

GT

no question just stating that his speed and rpm is normal.


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Title: Re: Top speed.
Post by: barracudajet on July 18, 2015, 12:04:05 PM

OK. I just expected more than that. At least the stereo is pretty loud. And it looks cool in my garage. Thanks for the feedback.

Title: Re: Top speed.
Post by: rush1 on July 18, 2015, 09:09:39 PM

I guess I won't complain I got 53 mph on gps I'm my 21 commander open bow sunseeker, do you guys have a diverter? They make a huge difference

Title: Re: Top speed.
Post by: barracudajet on July 19, 2015, 09:48:08 AM

I have a hydraulic diverter on my barracuda jet. I haven't played with it much. Can you hurt anything by moving it to an extreme up or down position at high or low speeds. There's no indicator of its position. What if you hold the button too long, obviously not more than say 5 seconds. Any advice.