Thanks Guys,

Though I would post an update incase anyone does a search for this topic and wants to know what I found.

I spoke to some people that test/clean injectors and they basically told me with these mechanical injectors (thin metal ones) that run on the KE injection system, it is not worth trying to fix them as they use a high fuel pressure, rather than electrical current to open them, and once they go they are not serviceable.

However since my motor has only done 50,000kms (1991 R129) then they would test them to see which was leaking so I could just replace that one. Hopefully the others will be alright as they should have a few miles in them yet.