Speaking to someone today who is 'in the know' he told me that the blanking plug on top of the oil filter housing is no good for an oil temperature sender. He suggested that the sender needs to be in the sump - is this correct? I'm in two minds...

Mines in the filter housing blank, seems to work fine...! Usually reads between 80 and 90 degrees unless you are on a private road (ahem) in which case it goes a bit higher.

Ok, thanks. That sounds like its working ok then. I don't suppose you know the size of the thread do you? I'm trying to find an adaptor as the sender I have uses an imperial thread :(

Can't remember off hand, i'll have a look in my gauge's box and instructions to see if it says. You could try www.gaugeplace.com where i got mine from as the sender i had screwed straight in.