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new build 241 vs 912

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new build 241 vs 912

Postby FlyLow » Thu Jan 31, 2019 9:23 pm

Lets talk about a new build and what pump you would put in.

Does the 241 produce more thrust than a 912? The 241 has a bigger intake impeller and nozzle.
I'd like to see some nice Scott graphs comparing the two. I think the masses would except that it is cost prohibitive to use the same boat.
When I look at the hydraulic system on the Scott it doesn't seem as clean and protected as the Hammi. Now that Hammi is throwing some weight around and dropping the price below the Scott is there a reason not to go with a 241? :Drink:
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Re: new build 241 vs 912

Postby Benny » Thu Jan 31, 2019 10:00 pm

I sure like the idea of a trim nozzle with inserts!
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Re: new build 241 vs 912

Postby mgrant » Thu Jan 31, 2019 10:05 pm

The trim nozzle was a game changer for my boat.
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Re: new build 241 vs 912

Postby Riverjohn » Thu Jan 31, 2019 10:29 pm

mgrant wrote:The trim nozzle was a game changer for my boat.

Did your Top end speed change from the 212 to the 912?
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Re: new build 241 vs 912

Postby Ahusk » Thu Jan 31, 2019 11:32 pm

Trash pumping ability and included stomp grate.
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Re: new build 241 vs 912

Postby mgrant » Fri Feb 01, 2019 1:42 am

Riverjohn wrote:
mgrant wrote:The trim nozzle was a game changer for my boat.

Did your Top end speed change from the 212 to the 912?


Yes, gained about 4 mph.
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Re: new build 241 vs 912

Postby chariotdriver » Fri Feb 01, 2019 3:36 am

FlyLow wrote:Lets talk about a new build and what pump you would put in.

Does the 241 produce more thrust than a 912? The 241 has a bigger intake impeller and nozzle.
I'd like to see some nice Scott graphs comparing the two. I think the masses would except that it is cost prohibitive to use the same boat.
When I look at the hydraulic system on the Scott it doesn't seem as clean and protected as the Hammi. Now that Hammi is throwing some weight around and dropping the price below the Scott is there a reason not to go with a 241? :Drink:


Great off season/cabin fever topic! The 241 is 30+ year old technology (slide-rule) with some shadetree engineering to make it work in the froth. The 912 was designed and built in the last few years with modern CAD and dynamic flow technologies. It's comparing a modern video game with PONG.

Concerning thrust; which is a product of mass X velocity (vs power which is MVsquard) guessing the 241 produces more thrust up to the 45-50mph range where it drops off though I bet the 241 is quicker to plane.

Chewing through garbage is a solid plus for the Scott products.

When I was putting my tub together the 575 and 912 were not options. Had they been available there is a very good probability I'd be running them. I have no complaints about the performance of the LSA/241 combo I'm running as it pushes 500hrs other than it's a bit of a gas hog.

Side note: we put many people on the moon 47+ years ago with a slide-rule; today we can't build a wall and it would take years to put somebody on the moon, AGAIN, with help from the Ruskies :)

Also, for now, the good deal on the 241 ends in less than 2 months.
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Re: new build 241 vs 912

Postby whee » Fri Feb 01, 2019 12:06 pm

Any chance we can include the American Turbine SD231 in this discussion? I know they were targeting the 212 so it may not be a great comparison but it sorta fits I think. 9.0" pump that was computer designed and according to the few reports out there it will pump trash and handle big hp engines. $8200 with hydraulic reverse. I can't tell if the pump has some issue that no one talks about or is AT has just done a crappy job marketing it.

Anyone have a SD231 coupled to a LSA or a 575?
I'm brand new to jet boats so don't listen to anything I say.
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Re: new build 241 vs 912

Postby mgrant » Fri Feb 01, 2019 12:57 pm

Just curious, anyone have a precise measurement of a 241's nozzle? I've never measured one. I started out with the 123mm insert in my 912, then switched to the 120mm to lower the WOT and cruise rpm.
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Re: new build 241 vs 912

Postby chariotdriver » Fri Feb 01, 2019 10:17 pm

mgrant wrote:Just curious, anyone have a precise measurement of a 241's nozzle? I've never measured one. I started out with the 123mm insert in my 912, then switched to the 120mm to lower the WOT and cruise rpm.


Of the two around here; on the boat plus the mis-hap left-over. One is 125.1mm with most of the lumpy paint missing while the other is 124.5mm with most of the lumpy paint remaining.
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Re: new build 241 vs 912

Postby No Worries » Mon Mar 11, 2019 3:01 pm

One important thing to not forget about is reverse. Scott 912 requires electric over hydraulic reverse, whereas the Hamilton 241 has true hydraulic reverse. In my eyes having separate levers for throttle and reverse wins. Especially when the reverse bucket is powered by true hydraulics that do not care about speed or throttle. I personally hate that little electric switch... Plus, a well balanced boat doesn't need trim. I have never had the desire for trim on any boat I have ever driven, except for a 25' twin. To me trim is just one more thing to go wrong and worry about. I have noticed trim-able nozzles definitely have an effect on the reverse cavitation also.

I am curious to see a comparison where the same boat, such as a 24', has an LSA with a HJ241 and a Scott 912.
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Re: new build 241 vs 912

Postby FlyLow » Wed Mar 18, 2020 8:55 pm

What rpm Does the 241 stop making more thrust?
I sure would like to see more info comparing the 241 and 912 especially concerning the LT4.

NoWorries; If Hamilton made a trimable hydraulic nozzle I would check the box.
After making my own trim tabs I wouldn’t be without them. They add quite a bit of versatility.
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Re: new build 241 vs 912

Postby Riverjohn » Wed Mar 18, 2020 9:46 pm

FlyLow wrote:What rpm Does the 241 stop making more thrust?
I sure would like to see more info comparing the 241 and 912 especially concerning the LT4.

NoWorries; If Hamilton made a trimable hydraulic nozzle I would check the box.
After making my own trim tabs I wouldn’t be without them. They add quite a bit of versatility.

241 is best up to 4000 rpm. We rode in Eric Schurman's 24' (I think) HCM last September thru Granite and Wild Sheep. He has the LT4 with the 912. It did not skip a beat and that included stopping in froth and then taking right off. It did not feel like a big boat with the way it accelerated. I don't know how the LT4 would like being limited to 4000 RPM with the 241. :Drink: :Drink:
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Re: new build 241 vs 912

Postby mgrant » Thu Mar 19, 2020 6:22 am

I do know the LT4 can actually blow the 241 out, like the LSA would do to a 212. I know a few boats with big Chev/Dart strokers and supercharged big blocks, their comments indicate that 4000 seems to be about the max usable revs, anything more didn't gain speed or thrust...which seems to be true of all the single stage axial jets.
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Re: new build 241 vs 912

Postby Eagle1 » Thu Mar 19, 2020 9:36 am

Anyone know the fuel burn on a LSX 454 with a 241 in a 24-25 hull ?
Last edited by Eagle1 on Thu Mar 19, 2020 7:32 pm, edited 1 time in total.
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Re: new build 241 vs 912

Postby ROCKBOTTOM » Thu Mar 19, 2020 6:09 pm

FlyLow wrote:Lets talk about a new build and what pump you would put in.

Does the 241 produce more thrust than a 912? The 241 has a bigger intake impeller and nozzle.
I'd like to see some nice Scott graphs comparing the two. I think the masses would except that it is cost prohibitive to use the same boat.
When I look at the hydraulic system on the Scott it doesn't seem as clean and protected as the Hammi. Now that Hammi is throwing some weight around and dropping the price below the Scott is there a reason not to go with a 241? :Drink:



I have to agree with the hydraulic part.The workings on the scott trim and other linkage on the back of the pump just plain look cheezy.Havent seen it myself but have been told that you cant use reverse with the trim nozzle up.Scott didn't re invent the wheel.They used a lot of other peoples R&D to build their pump.the 912 and the 241 both have good qualities.
Ill take the grey one. :Drink:
take what i say with a grain of salt and a sip of tequila,I might not know what im talking about
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Re: new build 241 vs 912

Postby mgrant » Thu Mar 19, 2020 8:56 pm

You can still use reverse, just not as effective unless you trim it down. There were issues with the reverse bucket breaking on the first production runs, however Scott issued a recall and sent out replacement buckets free of charge.

The nozzle trim is awesome, a difference of 5 mph in my boat by only adjusting the nozzle. Performance, there is no comparison with the 212 it replaced. I can best describe it as a 241's push, with impressive acceleration all the way to 4600 WOT rpm (configured at 4.05kw), at 52mph. Now with the capable pump, I swapped to the camshaft that I had originally intended for this stroker, replacing the small one I used to detune the engine for the 212, to limit uncontrollable blowouts.
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Re: new build 241 vs 912

Postby Upacreek » Thu Mar 19, 2020 10:38 pm

Riverjohn wrote:
FlyLow wrote:What rpm Does the 241 stop making more thrust?
I sure would like to see more info comparing the 241 and 912 especially concerning the LT4.

NoWorries; If Hamilton made a trimable hydraulic nozzle I would check the box.
After making my own trim tabs I wouldn’t be without them. They add quite a bit of versatility.

241 is best up to 4000 rpm. We rode in Eric Schurman's 24' (I think) HCM last September thru Granite and Wild Sheep. He has the LT4 with the 912. It did not skip a beat and that included stopping in froth and then taking right off. It did not feel like a big boat with the way it accelerated. I don't know how the LT4 would like being limited to 4000 RPM with the 241. :Drink: :Drink:


Did Eric have the LT4 that day we ran granite? I thought it was an LSA
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Re: new build 241 vs 912

Postby Riverjohn » Fri Mar 20, 2020 6:49 am

Upacreek wrote:
Riverjohn wrote:
FlyLow wrote:What rpm Does the 241 stop making more thrust?
I sure would like to see more info comparing the 241 and 912 especially concerning the LT4.

NoWorries; If Hamilton made a trimable hydraulic nozzle I would check the box.
After making my own trim tabs I wouldn’t be without them. They add quite a bit of versatility.

241 is best up to 4000 rpm. We rode in Eric Schurman's 24' (I think) HCM last September thru Granite and Wild Sheep. He has the LT4 with the 912. It did not skip a beat and that included stopping in froth and then taking right off. It did not feel like a big boat with the way it accelerated. I don't know how the LT4 would like being limited to 4000 RPM with the 241. :Drink: :Drink:


Did Eric have the LT4 that day we ran granite? I thought it was an LSA

I was pretty sure it was the LT4. Update: I confirmed this with Eric.
Last edited by Riverjohn on Fri Mar 20, 2020 10:11 am, edited 3 times in total.
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Re: new build 241 vs 912

Postby FlyLow » Fri Mar 20, 2020 8:49 am

mgrant wrote:I do know the LT4 can actually blow the 241 out, like the LSA would do to a 212. I know a few boats with big Chev/Dart strokers and supercharged big blocks, their comments indicate that 4000 seems to be about the max usable revs, anything more didn't gain speed or thrust...which seems to be true of all the single stage axial jets.



I wonder how big the letdown is to a new LT4 and 241 owner that they just touch 500hp?
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