Swordfish 120 Pro+ cutting out after motor upgrade...overheating?

[slowsl]

Hello guys. I've recently replaced my Leopard 3650 with a Leopard 3675. I've upped the prop accordingly, and kept the same speed controller which is a Swordfish Pro+ 120amp. The battery is a 4S 3300mah. The controller is rated at 120a continuous, 140a bursts. The motor is rated at 90A max. I've only tested through one battery pack, and the speed controller made a couple hard cut-offs, just like it would if the LVC came on. Letting off the throttle and giving it throttle again resets it, as it should.... The speed controller felt warm, not hot, but the log shows otherwise. The motor was barely warm. I reviewed the log, and it was as follows....
108Amp max.
12V min.
66 deg. C (150 degrees F)
28,554 max rpm.

I'm guessing 150 degrees is pretty hot for a speed controller, so maybe that's where they have the thermal cut-off set. Would it be safe to assume I have a water cooling issue, or is that pretty typical for 108amp on a 120A swordfish? I have the hose routed from my rudder, through the water jacket, through one side of the ESC, then 180 short loop back through the other side of the ESC, then out of the boat. I did notice that people recommend opening up the inlet on the rudder so that it tapers all the way to the leading edge.

[tlandauer]

From what size prop did you up to?
What battery? What is the C rating. That has a huge factor on the temp of the ESC. If the battery can't supply the current the motor is asking, the ESC is working over time.
3300mah is pretty low unless you are running parallel.
More info please. What is the kv of the motor? By math, I calculated 1929kv, so you shouldn't have a problem there.

[slowsl]

From what size prop did you up to?
What battery? What is the C rating. That has a huge factor on the temp of the ESC. If the battery can't supply the current the motor is asking, the ESC is working over time.
3300mah is pretty low unless you are running parallel.
More info please. What is the kv of the motor? By math, I calculated 1929kv, so you shouldn't have a problem there.

From an x438 to an x642. Motor is 2200kv. Battery is a single 4S (1p I think) 3300mah 35C. I thought if the battery can't supply the amperage, the battery just exponentially overheats. Here is a copy/paste someone replied on a different forum....

The 12V min reading tells me that you may have totally depleted the battery. That's 3.0V per cell.
The LVC would be cutting out.
What was the resting voltage of the pack after the run & how many milliamps were put back in the pack when you recharged it. Or, do you have a cell checker that shows what percentage capacity is left in the pack.
I feel the pack may be too small. A 4s 3300mah pack delivering 108Amps needs to have a C rating of at least 35C. What is the C rating of the pack?

I completely overlooked the 12V minimum reading from the log.... I had 3s stuck in my head, not 4s. The battery voltage 1/2 hour after the run was 15.0 volts. So will that amp draw surge the voltage that much? From 15 all the way down to 12?

[tlandauer]

You battery is too small and the C rating is too low for your set up. The prop is a huge jump from x438 to x642.
As said by Paul ( 785boats) , 12v min is way too low and the battery is not going to survive that kind of drain.
If I were you I will get no less than 5000mah and a C rating no less than 40C constant discharge rate. You should see if a x442 will lower the temp. 1.4 pitch is a good compromise .
Just my $.02!
Cheers!

[tlandauer]

From an x438 to an x642. Motor is 2200kv. Battery is a single 4S (1p I think) 3300mah 35C. I thought if the battery can't supply the amperage, the battery just exponentially overheats. Here is a copy/paste someone replied on a different forum....



I completely overlooked the 12V minimum reading from the log.... I had 3s stuck in my head, not 4s. The battery voltage 1/2 hour after the run was 15.0 volts. So will that amp draw surge the voltage that much? From 15 all the way down to 12?

Sorry, I didn't see that part. The answer is YES. It will bounce back, the voltage sag under load can be even bigger, depending on many factors: Lipo quality, age, C rating, etc.

[slowsl]

Sorry, I didn't see that part. The answer is YES. It will bounce back, the voltage sag under load can be even bigger, depending on many factors: Lipo quality, age, C rating, etc.

Never did the math with this battery, I see now it spiked to 108amps, and with the battery rated at 35C (115amps), that's probably cutting it too close. I see the relationship now between the discharge and capacity.