Oil pump priming


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Staff member
In case its useful, note that the gauge sender thread is 1/2-20 UNF tapered, and the idiot light switch is 1/2-18 unc(?) tapered. If you could find a barb or tail with the relevant thread it would be easy (and tidy) to pump oil in with a piece of hose.
Hi JP,

Are you sure that the two ports feature different threads? The reason I ask is my Rover's original engine had the sender and switch swapped over when they left the factory. They would not screw in if the ports had different threads.



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Wasnt completely clear before - the example was on an SD1 pump cover and its sender and switch. The threads were checked with a thread gauge so I am confident of those figures, and the idiot light switch will barely go into the other port 1 turn. If Leyland left these threads Imperial, but changed the pitch of one from P6 to SD1, doesnt make much sense to me. Mind you, Leyland did lots of things that didnt make sense back then. Sorry if I misled anybody. Thanks Ron.