Dana W

The KMB works fine I just think the 40mm impeller is alittle small for a Zenoah . Just make sure you use a good coupler . I'll be testing a different coupler soon . More info on that shortly . There is a customer here that purchased a DaVette Sprint boat that is installing a Graupner pump but havn't heard the test results yet . Maybe Scott can fill us in

timjz

My Feedback: (1)

What do the Graupner pumps go for? I can't seem to find a price anywhere. Also, do they offr a trim adjustment on the nozzle?

Scott Schneider

Funny thing, Dave just approached me last week at our race where I was running mine ... hey Scotty got time to put mine together ?
Sadly had to decline not having the time now spring/summer is here [] Seen the pump tho ... simple as heck & in no way close to the caliber of the Swash pump. Has an up/down reverse bucket and steering, No nosile trim.

daniel53

http://www.highperformancemodels.com...et%20units.htm
http://www.cornwallmodelboats.co.uk/...upner_jet.html

Yes I was looking at getting the 3 pin coupling that graupner make for the unit and zenoah

How about the hull any thoughts on the size?

Scott Schneider

daniel53

do you think with 780mm long the CG will be to far forward, think it will prime ok? or should I look for a longer hull?

infinityteg

personally i think that 780mm (30") is a little bit small for the ZEN and RCMK option. if you do go that route it is going to be one heck of a ride. Mine is 1m (40") long. the davette boats i think are around 36" mark (someone correct me if im wrong). the small the boat the harder it is goingto be to cram all the running gear in. As for the 3pin coupler. i think they are quite expensive for what you are getting. I just use 2 collets and a flex shat in between.

cheers
steve

daniel53

Hey steve thanks for your advise, im still pretty keen to give the small hull a try do you think there will be any other issues rather than just fitting the driveline in ?

Heres one Iprepared earlier the unit is just a guess as Idont know how long the inside part of the unit is? ive guessed 190mm

Scott Schneider

While a grey area in rigging it all ... using the smaller pumps like a KMB 40mm would be VERY TRICK using one of the Zenaoh 20cc engines with a marine conversion in a 30" hull

daniel53

Sorry Ididnt quite understand what you mean there? KMB 40mm?

I was thinking of a 49mm Graupner with the 30" hull and the Zenoah

Dana W

Yeah a 30" hull would work but I'd still make the engine compartment at least 20" . That will give you enough room to work inside . You'll still want to place your CG 9" from the transom . The DaVette Sprint boat is 34" long and I feel that's pretty symmetrical .

daniel53

On my cardboard model the rear of the engine is 9" from the transom do you think that would be about right?

dicko

I got a little more done. Here's some pics of the rollbar being mounted in the hull. The full process of building the carbon rollbar is over on the Snikwah forum.

infinityteg

Its going to be very tight but worth a go. to get the CG back enough you might have to place the radio gear above/around the drive line.

The KMB 40mm is a jet unit that Dana is using in his sprint boat. it has a 40mm ipellor rather than the Graupners being 50mm< Scott thinks that a Zen or Rcmk will be abit too much torque for the 40mm unit.

Where abouts in NZ are you. were more than welcome to come round and have a look at mine for some ideas if your in the auck region?

cheers
steve

daniel53

Unfortunatly im in Dunedin and Ijust about need a jet boat to travel around at the moment due to flooding
I think Iwill just have to give it a go and see what happens, it doesnt seem that im doing anything majorly wrong, will be interesting to see how it pans out. Would be nice to talk to some one that has used the graupner jet unit before to see how it performs

aussier6er

My Feedback: (-1)

guys i am looking to buy a jet unit does anybody have a swashdrive unit that they want to sell ??

i have been looking at the graupner unit but i would prefer to hold off untill i could hopefully find a swashdrive unit !!

thanks

Scott Schneider

The Swashdrive pumps are the gold standard in pumps and VERY sought after ..... hope you can find one

aussier6er

My Feedback: (-1)

after looking at the graupner units could someone please advise how these are mounted in to the hull ?

Dana W

I heard you glass it in . Similar to the KMB installation .

dicko

Here's the latest on my build. I've got the engine mounted, the radio box & linkages installed & all the trims set up. I had to make an extension to the coil relocator so that I could still use the over pullstart relocator, yet shift the recoil 90 degrees to allow the trim push rod room to pass the engine. I just need to drop it off to get the custom pipe made up & then get teh 29cc top end kit modified. After that I'll do the fuel tank & lines then test it before I add the design work.

I've added the pool noodle after I took these pics too.

Here's the pics.

Scott Schneider

Dicko,
Looking good !! .... your spacing of pump/engine/radio gear looks very much like my Davette build.
*What C/G numbers are you coming up with set up the way you are showing it ?

dicko

Hi Scott,

The COG with the pool noodles in & without the pipe or fuel cell is at the front of the rollbar. I'm hoping once the tank & pipe are in the COG will be at the back or just behind the roll bar. I have an excess of noodles in there now, I can remove some to move the COGfurther back if required.

Cheers
Jason

Scott Schneider

That is fine and good .. was looking for actual numbers tho

dicko

I'll measure it when I get home from work. I'm on my lunch break now.

Scott Schneider

Dicko,

Yours ..... [img]{akamaiimageforum}/upfiles/91577/At55190.jpg[/img]

Mine ..... [img]{akamaiimageforum}/upfiles/404891/Ge96653.jpg[/img]


So close in lay out .... I do need to scrunch mine up a bit tighter and move the CG back tho ... Maybe next winter, right not it's running and getting played with [:@]