Outer Limits 4x4 Board

what should a GQ Td42 alternator charge at? mine reads 14.7 volts, is this normal?

it's a little high...
optimal charge range is something like 13.8v-14.3v (someone might correct this, it's late and my brain is a little fuzzy).
if the charge rate goes too high you will end up boiling the battery and you will get all sorts of nasty fumes happening.

is it easy to fix or is there another alternator that i can put on?

if it is charging higher than it should be it will no doubt be a stuffed reg.
i'm not familiar with the td42 alternators, so i can't comment on ease of fixing...but i would assume it would need to be stripped down and have the reg replaced at a minimum...

From experience, I had to replace mine about 4 years ago (3 weeks before I got rid of the GQ )

You can't get parts for the original alternators anymore. The diode packs are the most common thing to go.

Why not take it to a battery place or auto elect to get them to put a meter on it - it could be that your meter is registering slightly high.

When it comes to replacement, there are new aftermarket units (55A from memory) available, or there are a few posts on here where people have found a 100 OR 130A compatible units.

The biggest drama with replacement is the vaccum pump on the back of it.

nov vac pump on alternator as mine is a 98 model td42 with vac pump under injector pump