Just removed my alternator using the excellent guide on here. Sure enough both magnets in the voltage regulator had broken off so I’ve a new one coming which should restore battery charging.

When I took it off I noticed that the vacuum feed on the pump at the back of the alternator was capped off. Does this pump produce all the vacuum & if so why would someone cap it off? What’s not likely to work properly with it like this?

I only use my K74 Warrior as a forestry truck so rarely go more than a mile or two at any one time. I have noticed that when it is hot & under load it misfires & loses power above 2250 rpm.

There is a capped off pipe on the vacuum pump which is used for testing.

Ah, that’s probably what I’m looking at, thanks 👍