Starting problem once in a while

[Big Aloe]

!993 Ranger runs fine most of the time, until once in a while it won't start. Installed a new starter and battery,
engine turns over and even when I connect the fuel pump directly to the battery it won't start.
Got it going by pulling the PCM power relay and fuel pump relay and switching them around.
When testing those relays though, they are perfectly functioning.(12V click and continuity test)
So I'm suspecting my ignition switch is failing at times.
How can I install a separate 50Amp switch to save myself the trouble to install a new ignition switch?

 

[Centaurious]

Replace both relays. Tests with multi-meters are not absolute tests as they put no load on what is being tested. I've had car batteries that tested full voltage and wouldn't light a regular test light. Your relays probably have bad spots on the contacts and occasionally they make contact just wrong and no current flows.

As for a separate 50Amp switch, you already have one called a Fender Mounted Starter Relay.

 

[Big Aloe]

Replace both relays. Tests with multi-meters are not absolute tests as they put no load on what is being tested. I've had car batteries that tested full voltage and wouldn't light a regular test light. Your relays probably have bad spots on the contacts and occasionally they make contact just wrong and no current flows.

As for a separate 50Amp switch, you already have one called a Fender Mounted Starter Relay.

Thanks Centaurious for quick reply. Isn't there a way to test the relays using an electric load?
As to the switch, I want a separate switch in the cabin just in case I get stuck.