Proboat Blackjack 29 1800kv motor getting hot....Anyone else had these problems?

[seabird1]

Hi.. some of us here in the U.K. have had overheating problems with the stock 1800kv motor and stock 80amp 6s lipo compatible ESC in the Blackjack.

When running the boat on 6s 5000mAh 40c lipo setup the motor gets very hot and in one or two instances the 3 wires to the motor (i should say that come out of the motor casing) have almost fused together, insulation melted.

On talking to Horizon Hobby here in the U.k., they said this.. If were using 6s in the Blackjack then we need to use the 1500kv motor from the Geico as it will run cooler due to the lower kv rating. They said the 1800kv motor gets way too hot on 6s as it can't cope with the heat build up. This makes no sense to us as the Blackjack comes with the 1800kv motor as standard, and is says 6s compatible on the box!

Id'e like to hear if anyone else had these issues on 6s lipo with the Blackjack 29??

Thanks

[srislash]

I would start with upgrading the connectors and prop tuning. You should probably run a smaller prop than stock. What is on it now?

[lenny]

Hi,

Your thread is misleading because of the header as blackjack 26".
We need to fix that.
Or you may not get much info or answers back.

Are you using 5.5 bullets for connector on the whole setup ?
If not,
That is the first thing I would do to help with the heat.

Post some pictures of your boat and the inside setup.

Hear is a link to some info.
https://forums.offshoreelectrics.com/...ng-6s-question

[kfxguy]

Hi.. some of us here in the U.K. have had overheating problems with the stock 1800kv motor and stock 80amp 6s lipo compatible ESC in the Blackjack.

When running the boat on 6s 5000mAh 40c lipo setup the motor gets very hot and in one or two instances the 3 wires to the motor (i should say that come out of the motor casing) have almost fused together, insulation melted.

On talking to Horizon Hobby here in the U.k., they said this.. If were using 6s in the Blackjack then we need to use the 1500kv motor from the Geico as it will run cooler due to the lower kv rating. They said the 1800kv motor gets way too hot on 6s as it can't cope with the heat build up. This makes no sense to us as the Blackjack comes with the 1800kv motor as standard, and is says 6s compatible on the box!

Id'e like to hear if anyone else had these issues on 6s lipo with the Blackjack 29??

Thanks

What prop are you running?

[kfxguy]

Btw, im almost 100% positive that a 80 amp esc isn't suitable for running 6s on a 1800kv motor. And your turning 39,960 rpms with a stock motor. It'll be fun while it lasts. Ill give you a tip to bring your temps down if you haven't done it already, "y" off your water hose to each the motor and esc and the "y" them back together before the exit hole. Sends cool water to each one instead of heated water from one to the other. Some people don't believe in this, but it does help keep temps a little lower. Check your temps before and after and you'll see.

[Doug Smock]

Merged the two threads and cleaned up a bit fellas.

[lenny]

Bad hair day again ?
That is just every day normal for me.

[kfxguy]

Hi,

Your thread is misleading because of the header as blackjack 26".
We need to fix that.
Or you may not get much info or answers back.

Are you using 5.5 bullets for connector on the whole setup ?
If not,
That is the first thing I would do to help with the heat.

Post some pictures of your boat and the inside setup.

Hear is a link to some info.
https://forums.offshoreelectrics.com/...ng-6s-question

Agreed. Hopefully he's not running deans connectors.

[lenny]

Ok hear is the info I was trying to find for you.
https://forums.offshoreelectrics.com/...-6S-won-t-work!

And this to.
https://forums.offshoreelectrics.com/...-have-an-issue

And upgrading the esc would be a good idea I think,
Because it is the weak link in the setup besides the connectors.

Hi.. some of us here in the U.K. have had overheating problems with the stock 1800kv motor and stock 80amp 6s lipo compatible ESC in the Blackjack.

When running the boat on 6s 5000mAh 40c lipo setup the motor gets very hot and in one or two instances the 3 wires to the motor (i should say that come out of the motor casing) have almost fused together, insulation melted.

On talking to Horizon Hobby here in the U.k., they said this.. If were using 6s in the Blackjack then we need to use the 1500kv motor from the Geico as it will run cooler due to the lower kv rating. They said the 1800kv motor gets way too hot on 6s as it can't cope with the heat build up. This makes no sense to us as the Blackjack comes with the 1800kv motor as standard, and is says 6s compatible on the box!

Id'e like to hear if anyone else had these issues on 6s lipo with the Blackjack 29??

Thanks

[hydro_pyro]

The motor is NOT turning 39,000 RPM. Haters need to put away their calculators. It doesn't run "no load" speeds under load. 30K to 35K rpm is more typical for 6s. This can be proven by measuring the audio frequency of the screaming motor as it passes by the dock. The factors that cause the overheating have little to do with RPM.

Jack your strut up above the bottom of the sponsons and add some negative (down) thrust angle, using the "dialed in" strut mods detailed in this forum. This will increase prop slip in the midrange so the motor sees less load. It will also help to lift the stern to cut down on bowlift and blow-overs, and reduce porpoising. You'll enjoy better handling, more speed, and less heat.

Balance the prop to reduce vibration.

I also cut two prices of roof rubber sheet and poked 3 holes to hold the motor wire connectors apart for better heat dissipation.

[96motorhead]

I have a stock blackjack 29. I run dinogy 65c 5000mah batteries in it and the motor gets warm but nothing that would burn my fingers if I touched it. I also go full throttle a lot so I don't baby it.

[Heaving Earth]

Btw, im almost 100% positive that a 80 amp esc isn't suitable for running 6s on a 1800kv motor. And your turning 39,960 rpms with a stock motor. It'll be fun while it lasts. Ill give you a tip to bring your temps down if you haven't done it already, "y" off your water hose to each the motor and esc and the "y" them back together before the exit hole. Sends cool water to each one instead of heated water from one to the other. Some people don't believe in this, but it does help keep temps a little lower. Check your temps before and after and you'll see.

Y connectors are a no no


Sent from my iPhone using Tapatalk

[Rocstar]

Ill give you a tip to bring your temps down if you haven't done it already, "y" off your water hose to each the motor and esc and the "y" them back together before the exit hole. Sends cool water to each one instead of heated water from one to the other. Some people don't believe in this, but it does help keep temps a little lower. Check your temps before and after and you'll see.

Terrible tip, why would you even suggest that? Water is going to take the easiest route and depending on a number of variables, his motor or ESC may not even see much water. If you're going to split water lines, it should only be done in a twin setup with the lines cut to the same length.

[kfxguy]

With all due respect, I tested it both ways and it showed about a 15 degree reduction in water temp in my testing. Im not sure why the y adaptors are a no no but they work just fine for me. What does ose sell y adaptors for?

[kfxguy]

Terrible tip, why would you even suggest that? Water is going to take the easiest route and depending on a number of variables, his motor or ESC may not even see much water. If you're going to split water lines, it should only be done in a twin setup with the lines cut to the same length.

Your over thinking it. Lines cut to same length? We aren't building rocket engines. Im sure you already know this but let me explain something to you. You have water being forced into the rudder. Line runs into the boat. Then y's off to motor and esc. Exit motor and esc. Then y back together and exit the hull. Water is going to go to both places. Are they both going to see the exact same amount of water? Probably not. Are they both going to get cool unheated water? Yes. I don't know about you but me, I'd rather have cool water to both components and not worry about if one get a touch more flow than the other. Like I said, your over thinking it. These are just toys anyway. Nothing serious. Just a way to have fum man.

[Rocstar]

Your over thinking it. Lines cut to same length? We aren't building rocket engines. Im sure you already know this but let me explain something to you. You have water being forced into the rudder. Line runs into the boat. Then y's off to motor and esc. Exit motor and esc. Then y back together and exit the hull. Water is going to go to both places. Are they both going to see the exact same amount of water? Probably not. Are they both going to get cool unheated water? Yes. I don't know about you but me, I'd rather have cool water to both components and not worry about if one get a touch more flow than the other. Like I said, your over thinking it. These are just toys anyway. Nothing serious. Just a way to have fum man.

I explained what you would use a Y fitting for. Fun until someone smokes an ESC trying to duplicate your setup without a proper understanding of how it works. Water will follow the path of least resistance. If his ESC has a longer line and/or smaller fittings then the motor cooling jacket, the water is just going to take the easy way around the motor. Great that it works for you and I'm all about trying new things, but to suggest someone else to do the same without an understanding of possible unwanted outcomes is reckless. If it were that easy to solve the single cooling line issue don't you think more people would be doing it? There is a reason no one else is setting up their systems this way.

[kfxguy]

I explained what you would use a Y fitting for. Fun until someone smokes an ESC trying to duplicate your setup without a proper understanding of how it works. Water will follow the path of least resistance. If his ESC has a longer line and/or smaller fittings then the motor cooling jacket, the water is just going to take the easy way around the motor. Great that it works for you and I'm all about trying new things, but to suggest someone else to do the same without an understanding of possible unwanted outcomes is reckless. If it were that easy to solve the single cooling line issue don't you think more people would be doing it? There is a reason no one else is setting up their systems this way.

Ok.

[BHChieftain]

There have been a lot of threads about running these boats on 6S. As noted above, 6S on an 1800kv motor is too many RPM. You can do it, but expect a shorter lifespan. Also, when the manufacturer claims the 80A ESC is "6S", they are talking about that ESC accepting 22.2 volts. However, 80AMPS is not enough headroom to run reliably-- it is very easy to burn out the ESC. You can run 6s with a very small prop, and get the same speed as running 4S on a larger prop... once you try to increase the prop to take advange of the 6s voltage, then the amps start to spike. You will hear folks say "my boat runs fine on 6s", but you will also find a lot of folks who have fried their components doing this. You hardly hear people having issues running on 4S on stock ESC. I would highly recommend upgrading the ESC for 6S.

I have a setup guide on this boat that talks about upgrades, connectors, prop selection, and also how to do a strut mod to take out the bounce-- it is a large word doc with pictures, if anyone wants a copy email me at

jqhydro@gmail.com

I have a very similar guide for the Miss Geico


Chief

[Darin Jordan]

the water is just going to take the easy way around the motor.

That is exactly right.... splitting a single water line with a "Y" config is going to starve one or the other...

I think that people are over-thinking this whole system. Has anyone ever measured the water temp on the outlet??

Anyone want to take a bet that there is no way that, in the short period of time that the water is in contact with the ESC and the Motor can, there hasn't been enough heat transfer to use up the waters capacity to carry away the heat?? In other words... the water exiting the boat is probably just luke warm at best... If anything, the water is passing through the system TOO quickly...

Some things that I KNOW help, are to:

1) Use larger water cooling lines to increase the capacity and SLOW down the water through the system
2) Open up the holes in the outlet and other fittings to, again, increase the capacity and slow down the water through the system.
3) Use only WELL PREPPED props... SHARP, THIN, and BALANCED...
4) The motor is going to get hotter than the ESC, and the hotter it gets, the more amps it draws, taxing the ESC more... Cool the motor FIRST, then the ESC.

I've been racing and beating on these boats since 2005, and I have never found the need to install dual cooling lines on anything. I have, just because it was convenient to do and was a special application, but for bashing or heat racing, one seems to be fine, if done correctly. But, then, I generally don't try to do things with power systems that they weren't designed to do. Attempting to go 60 with a RTR power system until LVC, for example...

[kfxguy]

There seems to be some conflicting opinions on this. Ill just stick to what works for me. Lol

[SloHD]

Opinions are all the same except for yours...

[kfxguy]

Opinions are all the same except for yours...

And that's just what they are. Opinions.....

[Rocstar]

And that's just what they are. Opinions.....

"Let me explain something to you." No one is disputing that it works for you, just that you are putting information out there as a one size fits all answer when that's not the case. There is a lot of experience on this board from builders and racers. No one wants to see a guy ask for help and receive advice that may cause damage to his system. If theories were not challenged and questioned the threads would be full of misinformation and become useless.

[kfxguy]

"Let me explain something to you." No one is disputing that it works for you, just that you are putting information out there as a one size fits all answer when that's not the case. There is a lot of experience on this board from builders and racers. No one wants to see a guy ask for help and receive advice that may cause damage to his system. If theories were not challenged and questioned the threads would be full of misinformation and become useless.

Your right. Just disregard my above post.

[iop65]

With all due respect, I tested it both ways and it showed about a 15 degree reduction in water temp in my testing. Im not sure why the y adaptors are a no no but they work just fine for me. What does ose sell y adaptors for?

Y-connectors !!



water will take the easy way to flow , when there is just a little difference in resistance , one "leg" won't get almost any flow
it's hydrodynamics (and resistance is futile when laws of physics are involved)

[hydro_pyro]

I mentioned setup a while back and it seemed to be taken with a grain of salt...

If you're running 6s and running higher speeds, the prop strut needs to be raised higher for more midrange slip and better top end efficiency with less load on the motor.

If your prop is buried too deep, You WILL roast your motor.

[mannytx1]

I use 5s and m445 never temperature problems

Protect your equipment make all your calculations to maximum voltage (cell 4.2v), Motor and Revolutions per minute (no more than 50,000 rpm)

Since each cell is 3.7v (medium = nominal) a 4s LiPo battery has a medium voltage of 14.8v,
a fully charged voltage of 16.8v and a maximum discharged voltage of 12.0v before damage occurs
a 6s LiPo battery has a medium voltage of 22.2v
a fully charged voltage of 25.2v and a maximum discharged voltage of 18.0v before damage occurs

LVC 3.4v/cell cut off no 2.9v o 3v before damage occurs
STO 3.85v/cell
no load
the first minute
4s 2200kv x 16.8v = 36,960 rpm max
5s 2200kv x 21.0v = 46,200 rpm max is too much
6s 2200kv x 25.2v = 55,440 rpm max bearing damage

4s 1500kv x 16.8v = 25,200 rpm max conservative

5s 1500kv x 21.0v = 31,500 rpm max = 4s 1800kv x 16.8v = 30,240 rpm max
6s 1500kv x 25.2v = 37,800 rpm max = 5s 1800kv x 21.0v = 37,800 rpm max

6s 1800kv x 25.2v = 45,360 rpm max is too much

[hydro_pyro]

PLEASE stop suggesting that the stock motor is capable of 40,000+ RPM on 6s power, because it's NOT! Put your calculator away, because those numbers assume ZERO mechanical motor load and ZERO voltage sag.

In the REAL WORLD, the 6s pack instantly sags several volts under load, and hydrodynamic resistance further limits the RPM well below the "rated" no-load KV figures.

Show me a stock BJ29 on 6s that turns more than a measured 38,000 RPM under running load, and I will eat fiberglass for dinner.

Mine ran nearly 60 mph with the stock ESC and prop, and it didn't turn more than 38K peak RPM at speed. I have ran it several dozen times on 6s with repeated wide-open passes, with no issues. The motor feels (and smells) a bit hot, but it runs great.

Renember... Professional engineers developed AND tested these products.

[mannytx1]

That's right, just for design ideal value, no load
I understand your frustration with the Proboat 1800KV motors, no corecto kv
I prefer Proboat 1500kv, Real +1600 kv if these are good
I do not need more speedMiss Geico (1).jpgMiss Geico (2).jpgMiss Geico (3).jpg
Miss Geico 4S Prop M445 o' x447(modified)
modified hull, no more WA WA WA .....