New Boat Genesis 56"

[Lutzy]

Hello, New member here, just jumped into electric RC boats after having gas boats in the past but my neighborhood stopped allowing them in our local lake, so I found one for sale locally, dont know too much about them to tell you the truth, the guy said he built it with some high quality components, and seemed like I got it for a good deal after he started saying how much money he put into the boat. The boat is ready to go, just waiting for amazon to deliver me some shaft grease to get it ready for its maiden voyage. It has NeuMotors 1530 /1y 8mm, ZTW 200amp controllers, (4) 4s 5200 batteries, DX5 pro controller & RDX1 charger. We had a slight language barrier since he spoke mostly spanish and didnt understand some of my questions. Hopefully I can search through the forum and find any information if needed. Thanks and wish me luck on my first test ride.

[fweasel]

Three things I would change before the first run if it were my boat...

1) Increase the gap between the drive dog and the end of the strut. Those are long flex cables and they will contract and shorten under power.
2) Get rid of the bullet prop nuts which are notorious for falling off and replace them with nylocs or zuber nuts
3) I would use a dremel cut-off wheel to remove about 5mm off the end of each brass stuffing tube so there was a little more room to clean off the flex cable before it slips into the motor collet.

[Lutzy]

Three things I would change before the first run if it were my boat...

1) Increase the gap between the drive dog and the end of the strut. Those are long flex cables and they will contract and shorten under power.
2) Get rid of the bullet prop nuts which are notorious for falling off and replace them with nylocs or zuber nuts
3) I would use a dremel cut-off wheel to remove about 5mm off the end of each brass stuffing tube so there was a little more room to clean off the flex cable before it slips into the motor collet.

Ok, I ordered some prop nuts, how much gap should there be about at the drive dog, theres a small washer in between, wasnt sure if it should barley just touch or not, and yes I will cut off to make space to clean off the end of flex shaft. I just noticed that on one of my shaft's theres a sleeve and the other side I dont see a sleeve, wonder if its why I got water in the boat?thumbnail (2).jpgthumbnail (1).jpg

[jkflow]

You have pretty long shafts, minimum gap is ~ diameter of the flexshaft plus the washer on that distance.
Yes, not having the liner in a shaft will cause water in the hull, you would have to be on speed to avoid that from happening.

[fweasel]

Can't see any of your pictures. Gap the width of the cable is a general rule of thumb, I usually run a little less, 3-4mm, and I typically don't bother with the washers. Without seeing the pictures, its possible the teflon liner in one tube is just pushed back, and doesn't extend all the way to the end of the tube. Water can get in from a number of places and a well greased stuffing tube is usually low on the list. Holes drilled for hardware on the rear of the boat is usually the cause, mating surface between drives/struts and the hull is also a common leak. Set the boat up and float it in a pool or bath tub with the hatch off and watch for any signs of water pooling up inside near those points. Cooling system leaks are also possible. Loose hose connections, pinched o-rings on motor jackets. A mild pressure stream from a converted garden sprayer is an easy way to test the system for leaks on the table.

[Lutzy]

Three things I would change before the first run if it were my boat...

1) Increase the gap between the drive dog and the end of the strut. Those are long flex cables and they will contract and shorten under power.
2) Get rid of the bullet prop nuts which are notorious for falling off and replace them with nylocs or zuber nuts
3) I would use a dremel cut-off wheel to remove about 5mm off the end of each brass stuffing tube so there was a little more room to clean off the flex cable before it slips into the motor collet.

You absolutely were correct on those bullet prop nuts, lost one on the starboard side, surprisingly & luckily I didnt lose my prop! I also left a gap about 1/4" at the dog drive/strut on both side, after running I noticed the gap closed up on the port side only. Both collets were pretty tight. I get my Zuber nuts tommorow, do I need to trim any excess thread beyond the nut after tighten down? theres about 1" of thread

[fweasel]

Excess thread beyond the props isn't an issue.

The cables only shorten under load. If the gaps were different after your run, the cables slipped in the motor collet OR the drivedog moved on the propshaft. The later can happen if the grub screw doesn't have enough room to engage on a flat spot on the sold propshaft, or, if the flat spot is too big and the grub screw gets pushed across it when the prop nut is tightened down. I like to make sure the grub screw in the drivedog is right up against the end of the flatspot shoulder, preventing it from walking forward.

[koen]

what i do to stop the drive dog to move, i use loctite 638 on the propshaft and grub screw

[jkflow]

You dremel/file a flat spot. Just deep enough for the grub screw to have a flat spot, i.e. very shallow. Nothing else will work reliably.