Pro Boat Formula FasTEC - MickieBEEZ Jet-Pump Conversion

[Darin Jordan]

As promised, I figured I'd do a build thread on converting a Pro Boat Formula FasTEC to use one of Mickie Beez Jet Pumps.

First order of business is to prep the hull.

Trimmed out some of the interior wood to allow motor mounting a pump clearance.

Located the unit on the transom and trimmed out the hole. I ended up taking too much from the bottom part, so I've made a plywood filler and have it epoxying into place now. There isn't a LOT of room around the seal ring on this unit, so you'll want to be VERY careful (more careful than I was this time around) on locating and cutting out the hole.

Power will be a new Dynamite/Pro Boat 1800KV motor and Dynamite 130A ESC. Will start this on 3S initially, and, if the pump seems to be able to handle it, I'll have the option of upping that to 4S.

Looking for set of factory turn-fins for this hull, by the way, in case someone has some laying around. The hulls I purchased didn't have them and I think they'd help with these application.

More to come...

[Darin Jordan]

A few more pictures....

I need to stop at the hobby-shop on the way home and pick up a 2mm tap, which is required to assemble this unit. You'll need a 1.5mm drill, 2mm tap, and a 1.96mm drill... which is really close to 5/64". I think that Dubro sells tap sets with the drill and tap for 2mm together.

The hole in the bottom of the hull is where the original driveline was. I minimally cut that out for now. Once the pump unit is located in the hull, I'll do the cutout for the intake.

[gsbuickman]

Wahoo, the nqd jet boats are fun to play with & build even though their chi-com junk. I am really looking forward to this one.

[Darin Jordan]

Did some more fitting and mounting last night.

Pump housing is now in place. I've shortened the stuffing tube to protrude about 0.800" out of the front of the housing. The motor will mount just forward of that. Considering looking at some alternate styles of couplers on OSE.com this morning. Thinking about the flexshaft style, just to help smooth things out a tad. Would make motor alignment MUCH less critical.

My one word of advice at this point would be to TAKE YOUR TIME fitting this stuff. There are not huge margins on the fastening areas, so precisely locating and taking your time to drill the holes accurately will help.

Still have to stop today and pick up a 2mm tap set so I can assemble the nozzle assembly.

I have drilled and tapped and counter-sunk the pump housing to accept the included 2.5mm counter-sunk screws.

[Darin Jordan]

Have the pump housing mounting in place and then started blending the bottom into the pump housing. There is a little extra material at the front, so I'm trying to blend that to allow for a smooth water flow into the housing.

[Norwest]

Darin, I built a Tear into boat and found I had to raise the read end up a little so I wouldn't loose suction. You shouldn't any problems as your keel is flat. Now as always, your project looks great.

[Darin Jordan]

Darin, I built a Tear into boat and found I had to raise the read end up a little so I wouldn't loose suction. You shouldn't any problems as your keel is flat. Now as always, your project looks great.

I thought about that...

When I used to race Jetski's, I had installed an intake grate, similar to the one in the attached pic. Seemed to help a lot. Was thinking that, if needed, I would add something like this...

[kfxguy]

Very cool project indeed!

[Darin Jordan]

More progress.

I got the pump nozzle assembled last night. I decided to change the fasteners, however. Two of the Metric 2mm screws seemed to be too short, and, even using great care, seemed to strip out of the plastic easily. I think the super fine thread pitch is a problem. I upped the holes to 2-56 and they seem solid now. Screw length is CRITICAL, so make sure they are long enough, but not a fraction longer. Otherwise they'll bind on the pump housing.

Once these were fitted, I put a dab of blue-loctite on them and threaded them in, running them down until they JUST touched the tile and steering rings, then letting them set overnight so the loctite could setup. If you don't use the loctite, they'll un-thread themselves when the nozzle is adjusted.

[Darin Jordan]

For some reason, I didn't get any pictures of it last night, but I sealed and installed the pump unit to the hull. I basically put a bead of clear silicone around the flange, and bolted it in place. I had to add some additional 4-40 counter-sunk screws to the mounting. The provided 2.5mm screws, again, seemed to strip out the plastic pretty easily, especially with the deeper counter-sinks. The 4-40s didn't require the deeper counter-sink, so there was more plastic left to grip to. I think the courser thread pitch helps as well.

Anyhow, once that was bolted in place and setting up, I was able to fit the rubber transom seal and sealing ring to the pump-to-transom area.

I used a piece of bike inner-tube to make the "thin rubber" sealing plate for the transom. This seals the pump housing to transom hole. I just traced the transom "ring" (hex plate?? ) and cut the rubber out with some scissors.

Once it was fitted in place, I pre-drilled the holes, opened up the hex-ring for clearance holes, and bolted the assembly to the transom.

I would probably recommend, and will do this on the next conversion I do, that you opt to replace these transom fasteners to something smaller. The provided stainless fasteners are larger than they need to be, and require a high-level of precision when locating the big pump hole in the transom. Make it even a fraction too large, and there isn't enough material to keep these from breaking out of the material.

Just take good care when you are installing this stuff. It's a nice kit, but you need to be aware when threading into plastic.

[Darin Jordan]

A little more work done last night.

Have the motor mount all lined up and epoxied in place, and I did the final mounting of the motor and fitting of the drive-shaft. You can see the tap I added to the stuffing tube to allow me to keep the shaft lubricated. Should make maintenance easier.

Had some issues fitting the push-rods to the nozzle. The steering arm is very fragile on this unit. After I carefully fitted it with the smallest ball style push-rod fitting I could find, it snapped off just ahead of the fitting. I decided to come up with my own steering setup. Not ideal, but it'll hold up. This was done with a 4-40 stainless screw and some aluminum tubing. The next time, I'll see about using a smaller setup so as not to impede the nozzle outlet quite as much. I'd like to see a much stronger steering arm on this nozzle, however. I may contact Mickie about this.

Used .032" stainless push-rods from Dubro. They seem to be rigid enough for the task, and they fit through the supplied thru-points nicely. Drill through the transom with a 5/32" bit and the Teflon sleeve fits snugly, providing a fairly water-resistant seal (remember, it's also passing through the rubber seal I installed previously.

I decided to break the pushrod inside the hull and used a wheel collar to fit the inner rod to the outer rod. Makes installing much simpler and can be adjusted easier. The inner rod is actually .047" stainless wire. Makes the system a little more solid.

Second servo was added to control the tilt. This was simply double-back taped to the pump housing. It's a Spektrum A7020 Digital Aileron Wing servo. Nice and small but durable. Should work nicely.

I'll hopefully be finishing this up enough to test here in the next day or so.

[Fella1340]

Some of the things you've experiencing I had wondered about. This pump is no a buy and assemble unit as it appears more of a build on its own. I hope to see this hull running hard on the water without any of the hopping around I have seen to date on these. Goodluck, if you have success I may just try one out. Thanks for taking the time to post the hurdles, it gives a much more realistic expectation level
Jeff

[cybercrxt]

Darin, Did the instructions come with a pump efficiency curve of any kind? I was just wondering what rpm it is designed around as I suspect if you exceed the sweet spot it may induce cavitation. I have always wanted to do a jet boat...but...lack of time as usual! Mike

[Darin Jordan]

Darin, Did the instructions come with a pump efficiency curve of any kind? I was just wondering what rpm it is designed around as I suspect if you exceed the sweet spot it may induce cavitation. I have always wanted to do a jet boat...but...lack of time as usual! Mike

Mick suggested that it was designed around a 28,000RPM limit. I'll be pushing that with an 1800KV Dynamite/Pro Boat motor, but I'll run it on 3S first. If all works out, then I can swap in a 4S pack and push the pump limits.

I have some upgrade ideas for the pump itself that may help it to be more durable and more efficient, but we'll see how it holds up "stock". It's a nicely made and designed unit, but I always find room for improvement... :)

[Darin Jordan]

VERY IMPORTANT UPDATE: If I mentioned using Loctite on ANY part of this pump, PLEASE DON'T DO IT!!

I found tonight that wherever I had applied the blue Loctite, the plastic had become very brittle and melted in some areas.

I ended up completely replacing the Steering Nozzle assembly tonight. I had ordered two of these kits, so luckily I had all the extra pieces.

This time around, after I located and drilled the holes for the tilt and steering pivots, I did NOT use the 2mm tap, as described in the original directions. I let the screws "self-tap", and they stayed a lot more secure this time around.

So, this time, the steering/tilt assembly looks as it was intended, without needed to modify the steering. I'm going to be very careful with the steering part, however, as that arm is still a weakness in my opinion.

I drilled the pump housing and threaded in a barbed fitting for the water cooling pickup, as described in the instructions.

Got it all together and was able to get the ESC installed, and the remainder of the systems in place.

ESC is a Fuze 130A Sensorless BL Waterproof ESC (http://www.horizonhobby.com/products...ct-1-8-DYN4955).

Motor is a Dynamite 1800KV (Pro Boat).

Due to the motor location, etc., I decided to use a pair of 2S packs and run them as a 4S system. RPM range should be about perfect for this setup.

The last few things that need to occur are:

1) Make flat sub-hatch to go over hatch opening so it's easier to tape the hull closed
2) Install a 3-channel ESC (setup was done on the bench with a 2-Channel MR200)
3) FLOATATION, FLOATATION, FLOATATION!!