Hi all, recently found and registered on the site. Please excuse any "dumb" questions. I am brand new to the RC game with the recent purchase of a used BlackJack 26 brushless boat (appears to be in "like new" condition). As far as I can tell from reading some info on here, my boat is 100% stock.

I purchased new batteries and a charger when I bought the boat from a dealer. It seems to run ok...until I squeeze the trigger past approx 1/2. It cuts out. If I return the trigger back to rest, then start going again ok...of course until I try full speed again. The weird thing is, when I remove the boat from the water and it's on the dock, I can hold the throttle wide open no problem (I know, only for a second). I have tried to reset the ESC? by following the instructions, but that doesn't seem to have done anything for me.


Anything you can think of for me to try next would be appreciated. Remember...lamens terms...lol

After reading some excellent posts on the site, i was planning on getting the Aeromarine kit for the boat soon...any other items, or suggestions for the boat?

Regards and thanks for any help
ZS

Sounds like the ESC just isn't capable of providing enough current for more than about 1/2 throttle when under load (prop in the water), it's ratings are being exceeded. When run at about 1/2 throttle for a while, does anything get uncomfortably 'warm'? At least that's my first impression. I think I'd check the wiring and connections, make sure they are good, and take a general look at things. Anything seem maybe not exactly 'right'? From there, your guess is as good as mine...
- 'Doc

Sounds like poor quality packs are being used. Brushless power requires top quality packs as the cheaper packs can not provide the current demanded by the motor. When the motor demands this high current the pack can not provide it creating a large voltage drop and tripping the LVC or stalling the ESC.

This issue is extremely common for new boaters to the brushless world. If you do a search there will be several others with this issue.

LiPo is highly recommended. Or at worst case use only IB or GP cells of 4200mAh or higher.

In a couple weeks the canadian nationals fast electric race will be held in London. Check out RCU's event listings if you are interested.

Ryan

Thank guys. The batteries that I am running are Venom 3000NiMH...I think you may be correct on the power thing. I will look into the LiPo option. What would you recommend for brand or size? Where can I go? I bought the boat from AVF on Dundas here in London. They seem to know what they are doing, but being as I don't know any better...do you recommend them?

I will def check out the races here in London. I presume that is at the location I've seen out by the 401.

Thanks again ZS

The pond by the 401 is holding a race this weekend but will be for nitro and gas boats only. It's still worth the drive to see how they do it. Contest Director Mike Hallam is one of the most fanatical R/C boaters that I've ever seen and I've seen a lot!
If you go, look up Randall Thomas as he does electrics as well as nitro. The dude knows his stuff!

Perhaps a smaller and/or less aggressive prop would allow the motor to spin up with less loading and give you the full control range. Picking the best prop in any particular situation is a true black art, and the subject of much discussion.

If the batteries are brand new, you'll find that they need a couple of cycles before the deliver full power, how often have the batteries been charged? With what charger at which charging current?

Also, NiMh need to be run warm from the charger, not charged the previous night, specially if a brushless motor is to be 'fed'.

Regards, Jan.

A brushless that cuts out under load at half throttle is usually a bad speed contro(regardless of batteries). It's (sometimes) happens when the speed control fries one of the 3 phases of A/C current to the motor. Two phases will make it spin but no torque. Another big symptom of a missing phase is the motor(s) not starting until you give them a little spin...then seeming ok until they're under load.
my $0.02