Thanks guys, I have tried getting the blanking plug (4 months no sign of it) I am only aware of one place in the US that supplies these and my plug went missing in the mail (money refunded) apparently this happens a fair bit for items to Australia so I gave up with that supplier and hence was thinking this may be a cheaper/reliable? alternative.
Didn't know Lotus supplied a blanking plug and retaining plate but will do a search. Thanks.
Do you think there needs to be some resistance on the impeller? It is run off the oil pump which would supply resistance in itself.
Worst case scenario I can think of is if oil passes into the impeller housing and feeds grit back into the lubrication system. There will be no coolant in there, just a worn out impeller.
dodge1979, I am using the Davies Craig electric booster pump I have seen others using (supporting Aussie manufacturers).