battery switch earth terminal melting

[richievtu]

Morning all
The battery isolation switch I use for the starter battery is the cheap on off type with removable key & is wired to the earth wires.
The terminal that has the cable connected to coming directly from the battery has melted a number of switches in a short period of time.
Engines do take a bit of cranking before firing up and the cable at the switch end is getting warm, clearly!
Unsure why? The cables that go to the opposite terminal on the switch, one of which is grounded to an engine are not getting hot, is it simply a case of getting a better switch?

 

[pvb]

It's possible that the switch isn't up to the task, or that the terminal-to-cable connection is faulty. You could swap the terminals around and see which then gets hot to determine your course of action.

 

[Bilgediver]

Is the cable between the switch and starter the same size as between the switch and battery. Maybe the cable to the battery is undersized.

Some of the switches available in Swindleries are poorly made and not rated at more than about 100 amps. Look for a better product as some are rated
at 300 AMPS . I had a cheap one that had a short life a few years ago

 

[Spirit of Glenans]

Beware of excessive engine cranking, it can result in flooding your engine with seawater, which can have expensive consequences.