DRAGONFIRE81M

looks great man . are you running one or two batterys .

DRAGONFIRE81M

well after running it dirct drive throw a grumpner ujoint . it was kicking butt . till the set screw lossen up on the pump shaft and i over reved it and boom went to joint only on the motor side the plastic faild . the weakset spot . had to get a fishing pole to get it back .

Quicksilver

Sorry I thought you knew what it was. I was going to go true flex, but that would have been significantly more work. I figured, well theres only 3" of shaft left anyways. The only tricky part was I had to make a new stuffing tube and make bushings but that really wasn't even hard once I knew what I had to do.

I see what you mean though, it does require a bit of room. However what you could do, which would be similar is to make the coupler in the the tube. So basically you take out the original stuffing tube, Cut the shaft down to an inch or so, slide the 3/16" OD tubing over the entire shaft. Then just leave about an inch of tube to insert the flex into. Than and this is hard to explain in words, put another tube over the 3/16" tube, this will be your bushing Now using a 1/4" tube cut to the length of the original stuffing tube install that in as the liner and bushing holder. This effectively would give you a true flex drive.

I'm going to try to draw this since I cannot hardly understand what I just typed.

DRAGONFIRE81M

yeah that was what i thoght you did since i know you used the stock shaft and impeller . the only thing i need to buy it the bushings for a 3/16 strut . and a 30mm 3/16 prop to cut down.

man i put the cooling comeing out the back now . insted of going throw the oil fitting on the drive and put a pice of fuel tubeing there and filled it with 3in1 oil . but any way i have a 12" strem comeing out the back . it looks like a yamaha or kawasoki cant remember witch one has that

Quicksilver

shoot, I made a drawing and left out a piece

edit; saw your post, ok well then were on the same page.

Quicksilver

I will warn you shoving that 1/4" tube into that drive wont be easy and it needs to be very precise. Might want to make some sort of support to ensure it stays in the right position, while you're drilling.

DRAGONFIRE81M

did you use a 1/4 in your set up . b/c i measred with a type not a mic . it was pretty close to the same size od as a 1/4 brass tube. if you havent relised i can remove my stock stuffing tube

oh btw have you thought about useing a 3 blade prop . if i did stay with a 4mm thread shaft i mite try it http://www.offshoreelectrics.com/products.php?cat=57 its the first one

the last one i forgot a 7/16 bushing for the 3/16 cupler or prop shaft witch i got in both alum and brass to see which will work better as a brushing

some more pic this is the sec drawing with the 4mm stock prop im going to also make the other one two as a backup using a 3/16 prop shaft . also insted of drilling it out i just heated the brass stuffing tube and pushed it threw the hole it cut the shap realy nicely and only removed the super glue that i used to put the intack together . oh yeah the pic of me holding to stuffing tube up is showing the 7/32 alum bushing that i drive in . which it replaceable . if it wares out .

DRAGONFIRE81M

she's al together again . here is some more pics . to be safe im not going to run her till tomarrow to let the glue set good be for i let her rip . hey qiuck what do you use the lube your flex cable ?

j.m.

marine grease.

Quicksilver

Glad to hear it's back together!

sorry about my absence. I use lithium grease. I lube it AFTER every run. That way it doesnt get put away wet

That's a little weird using marine grease, what do they use? like dove moisturizer....it is hot in the desert, probably get pretty dry.
but actually marine grease would be a really generic way of saying, a lithium based grease, but imo more expensive

fvega

I am trying to decide on a good hull for a Jet drive any thoughts about the hulls from
www.btorcboat.com,
or
32" or 25" from
http://stores.ebay.com/Head-of-the-R...QQftidZ1QQtZkm

fvega

What is the height of your transom in the shockwave 26?

j.m.

you need a thick grease that doesn't mix well with water. (i.e. it makes water not get in the boat)

I just said marine grease because it is very easy to find where i live.

(it's all over my garage!!!!)

DRAGONFIRE81M

thanks j.m. and qiuck ill use lithium grease since i have plenty of it here i also use it on my ski and boat .

DRAGONFIRE81M

i would thank this one would make a good hull for a jet drive . http://cgi.ebay.com/25-Fibre-glass-d...742.m153.l1262

i even like the race kit for this hull thanks for the link to that ebay site .

Quicksilver

I was just joking I used to have lots of the stuff for my OB, but now I'm reduced to a spray can right now, but it does do the job and it get nice and deep in the cable, but very messy.

dragon-nice hull choice, looks like the one I was going to get many moons ago.

j.m.

you guys would have much better luck with your drives if you used 3 or 4 blade props, instead of 2 bladed props.

Jets are actually the most efficient with an impeller design that is almost like a ducted fan prop.


Look:
http://www.performancejet.com/NEW/IMPELLER02.bmp

Vinnystoolbox

What are the benifits of using the flexdrive?

I have a Graupner flex coupler in my box of bits that will be becoming a jet boat in next little while.

Just got the hull and jet drive a few days ago, so starting to build the drive up at the minute.

The hull is a CEN aquajet rtr so having a bit of fun before i butcher it to much.

Have already done the water cooling outlet though.

DRAGONFIRE81M

man has far as the flex drive goes its perfict thanks qiuck . it handles the power just fine so far . sorry i still didnt get any video the fuel tank started leaking and the motor was leaning out . im going to post and look at the nitro vee thread for a good fix . i had replaced it when i first got it and last week i epoxyed the leak but it didnt hold im going to take it out and see what happed but i thank between the mathinale and caster oil it seprated the epoxy . i mite even need a larger flywheel or some weght . and im going to have to add some larger screcks to the bottom. it got a little swarly at top speed just before the tank presser dropped .

vinnystoolbox the reason im useing a flex drive is b/c i had to much drive angel and not anof room for a flex coupler . and the grupner joint u-joint wasnt strong anof . which i found the peace on the dock today the joint didnt fail it was where the plastic is glued to the metal . oh and also when i tock the old drive shaft out it was bent on the tip .

yeah j.m. i comented to qiuck about 5-6 post up about cutting down a 3 blade prop if i stayed with the 4mm shaft . well when i run to hobby lobby im going to pick up a 3 and a 4 blade . also i need to het up a frend of mine on here that makes custem impllers . here is some of his work its a drive for a sub

j.m.

Those would be PERFECT!

They would slip a LOT less than your current 2 blade, and they would be more efficient, too.

Quicksilver

excellent!
Umi made up some 4 blade impellers once, but the results were mixed, don't think she really liked the results. I would recommend to those who have the time, to cut down a 3-blade 45 or 50mm CF graupner prop and try that. I think as I've said somewhere long ago, that the impellers used in the kmb(28mm) and graupner(29mm) drive is a cut down 45mm prop. A 50 might give a bit more bite and pitch.

dragon sorry, I corrected your post, I was bored..........you should get mozilla firefox, it has built in spell check.

DRAGONFIRE81M

really its ok i don't mind . and yes i do need to . i have been meaning to . for that and i can watch Japaneses naruto in higher quality . still a kid at hart well most will say im still a kid anyway . and also thanks for a prop size after looking close at the impeller i could tail it start out a lot larger . but anyway the 4 blade only comes in 50-60mm

j.m.

it still wouldn't hurt to try a 4 blade 50mm.

DEFINITELY de-tounge it.

hooked !

Had the SW jet out for a run I notice splash back on the jet when turning
just live with it ? graupner 29 mm

DRAGONFIRE81M

yeah quick has tried to make a seal for it i thank it was a balloon. but it just tiers . as for me i just live with it .