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[Captain Flack]

My son has a 3ft trawler which he picked up second hand.  It came with two  motors and fitted shafts and props. so I assumed that 's what it is supposed to have.   To get it on the water (cheaply) I fitted it with some spare  Escs which I had in the drawer.
This is the setup:
2 x 380 motors turning M4 shafts with 2 x 3 bladed brass props.  2 x Blue Chinese ESCs. 3300mAH 7.2 V battery with single 20A fuse.

It has a fair turn of speed but the motors and EScs get very, very hot, the fuse doesn't blow.

Set up on Radio Link TX & RX with a motor on each stick.
I beleive the model is a Polar North Sea Trawler.   Any ideas?  I am wondering if it's overvoltaged, or over propped.   There isn't much more room for bigger motors, and whilst I know about Chinese ESCs, I am sure that these are rated highly enough to handle the current.

[Time Bandit]

Too much rpm on the motors and probably prop with too much diameter/pitch.
Basically I donīt know any 380 size Johnson/Mabuchi that makes sense to use in a non gliding boat.
Most of them do > 15k rpm.

Only chance will be to use the low pitch Graupner props or you change to a lower rpm motor.
With 30mm brass props they should do around 4000 1/min under load.

Iīm not so sure about the market for motors in the UK. Here I would suggest to use a Buehler motor.

[inertia]

Swap the 380 motors for 385's. Much lower RPM; same mountings and shaft size. MFA import them; Component Shop sell them (among others). They are not expensive.
Props should be no more than 30mm diameter.
Bin the ESCs and fit some proper ones.
Dave M