help me with my mystic 29

[skinroy]

hello new to the site and electric boats also,have had a ton of gas powered cars tho
i just traded for a mystic 29 and am having problems with it,when i run 1 battery in it everything works great but as soon as i use a series connector to 2 batteries i lose power when i go full throttle,i can go slow butt whenever i hammer down i lose power,i have of course checked all the connections and cant seem to find anything loose.i am using onyx 8.4 4200 batteries,also have a spektrum dx23 dsm radio and reciever that beeps a bunch when turned on, maybe thats part of it ?idk any help is appreciated thx

[Cinnabun]

2 8.4v packs should put the esc past its input voltage.

Also, the esc may be in lipo mode, and when you hit the throttle the voltage is dipping down below the lvc voltage and it's putting it in limp mode

[skinroy]

how would i change that?i did some googlin and dont see a reset button on the esc, i beleive it has a programmable 60 amp(4s compatible)water cooled esc.i read that online somewhere fwiw
am i just using the wrong batteries?kinda sucks if so cuz i just bought like 200 dollars worth of batteries and a charger

[SloHD]

You might need the proboat program card...

Why would you buy nimh batteries? Lipos are ALOT better, and pretty standard these days.

Look in the proboat forum here. You can learn a lot just by lurking through the threads...

[skinroy]

that was what i was told at a local hobby shop, i brought the boat to them,when i got the boat it had no batteries or controller.not gonna be to happy with them if these are not gonna work

edit i just foundthe mystic section in the pro boat rtr q and a section,should i be posting there instead?

[SloHD]

We won't kill you for posting here. A mod will move this thread to there eventually...

If possible, take those batteries back and tell them to sell you some lipos. Direct wired packs, not bullet packs.

[SloHD]

While you're there, get some bigger bullet connectors for your wires too. Most use 5.5mm.

You'll also need a bigger bullet connection for your battery connector as well. I use castle 6.5mm connectors.

[skinroy]

ok so i just got off the phone with the hobby shopand they are telling me that it should not exceed the input and to bring the boat in because they do not normally return batteries
idk what i should do

[Flying Scotsman]

That "hobby shop" is full of you know what!!!!.......Tell them that it would be in their best interest to give you your money back on the batteries or replace with suitable batteries (li-po)

Douggie

[Cinnabun]

http://www.proboatmodels.com/Products/Default.aspx?ProdID=PRB4075

Show them this link.

Input voltage is 2 - 7.2v Sub C cell batts or 2 - 7.4v 2s lipo batts.

You're overvolting the esc.

[skinroy]

thx cinnabun i also have some 7.2 v venom 5000 batterya i just borrowed from a freind and the same thing is happening,it does go much faster before it cuts out tho,i cant get up to the hobby shop til tomorrow also

how do you change the esc from lipo to the other,if even possible?

[skinroy]

also if i run these batteries paralell instead of a series everything seems fine its just way slower,will i mess it up if i continue to use it this way?

[Cinnabun]

You really need to grab a set of lipos. I wouldnt suggest running the NiMh batteries.

[tlandauer]

You said when you bought the boat there was no ESC, so which one did you end up using, I ask because if you have the PB ESC, as suggested above, you can get a program card , the little tab/switch can then be set for Nimh.
Also on my 1st generation ESC ( FasTech) it was possible for people to use higher than 4s lipo setup which in a moment I will explain.

I hope you can return or at least exchange for lipo batteries at your Local Hobby Shop which really is responsible for a large part of your problem, try to return the batteries and simply state that this is the wrong type for the ESC. I totally agree that you need to go to lipo because the performance would be so much better and the ESC won't be misreading the voltage and cell count.
As stated above, two fully fresh charged 8.4v NiMh battery packs will be above the 16.8 v charged voltage of a 4s lipo ( each cell of a lipo read 4.2v fully charged at the charger). My 6 cell 7.2 NiMh fully charged read 8.6 v at least and it is a cheap one, so when you put in batteries that read more than 16.8 volts, it is possible that the ESC is counting 5s, ( 5s lipo @ 3.3v/cell=16.5v---partially depleted but may still be above ESC's cut off threshold for 5s lipo count) then under load the voltage quickly drops ( a trait of NiMh), the ESC kicks into Low Voltage Cutoff and puts you in limp mode. This applies to ESCs that read from 2s-6s lipo, that is why I asked what ESC you are using.
Same situation with two 7.2 sticks: when they are fully charged and taken off the charger, they read way more than 14.4 volts, may be not at 16.8 volts but now a 4s lipo's fully charged reading is 16.8 volts, so it is not very far, this is above the cut off threshold and thus the ESC is tricked into thinking that it is a 4s lipo, but when you put it under load and the voltage drops, you enter Limp Mode again.

[skinroy]

i beleive the esc is the stock/one that came with the boat,i meant it had no receiver or controller,i am going back to the hobby shop in the morning so hope to be able to trade this stuff in.when i go in what should i ask for?