Can anyone help thanks

Can anyone help iv got a 1990 mk1 clipper and when the cars been running for a wile the oil light comes on and keeps buzzing i drained all the oil when i serviced it and replaced it with good oil at right level but it still keeps coming on.
douse anyone know why this is. also im about to put my car on the road douse anyone know how much it is to tax a mk1 clipper 1.8 thanks

Guessing the tax will be about £112 that's what I've just had to pay for 6 month and the oil, not sure to be honest did you put the plug back in properly and bot dumped your oil all over the floor?

if it keeps flickering and you have got plenty of oil in then your oil pressure switch will be playing up

try running a long bit of wire from the earth terminal on the battery and connect it to the oil pressure switch plug and see if the light stays out all the time if it does connect it back up to ya switch and see if it plays up on the dash  if it does then your switch will be faulty

Tax wise, if you go on the DVLA website type in your reg and vehicle make you can see what the cost will be.

http://www.taxdisc.direct.gov.uk/EvlPortalApp/application?origin=vehicleEnquiryInfo_en.jsp&event=bea.portal.framework.internal.portlet.event&pageid=Vehicle+Enquiry&portletid=VehicleEnquiry&portletns=VehicleEnquiry_en&wfevent=link.next

Useful for finding out cost for prospective purchases too

Faulty engine internals/ oil pressure switch's/ oil pump/ pick up blocked.
Location?

Taxed mine on the 2nd of March for 12 months. I have a 1991 1.8 carb clipper. That was £205 for 12 months if that helps?

Oil light could be faulty sender.

Mine had that problem once when on the way home from college(a long time ago). Something in the oil filter/oil cooler housing was sticking and sending the buzzer and light on.
Engine didnt sound very good either.
In desperation(28miles from home and no AA) i smacked it with my Krooklok….cured it though!  

Ok thanks for all your help ill try and have a look and try the thing you have all said. again thanks for your help.