Re: 87 yamaha 115 precision blend oil pressure sensor leaks
its not a sensor, the engine mounted tank contains a 3 position reed switch activated by a magnetic float, float all the way up sw1 closes and commands a transfer pump off,sw2, float about midpoint, closes and commands transfer pump on, float at lowest pointsw3 closes and commands an alarm,a visual indicate on the tach and rpm reduction.
swb in the remote tank contains a single contact reed switch with a magnetic float, swb closed and you get a green visual on the tach and automatic transfer is allowed, remote tank low swb opens you get a yellow indicate on the tach and automatic transfer is prohibited.
so back to how is the engine tank mounted switch being forced out of the tank, either its not venting and when oil is transferd and is compressing the air in the tank it pops OR the transfer pump is failing to shut off.
precision blend is an incredibly simple system that whales technicians butts on a daily basis cause most folks cannot track 3 or 4 things happining at once apperently.there are 2 basic versions for the V$ biggest difference is in the oil control module,late style uses a pulser coil signal to allow auto transfer and the older a mercury switch. 3 basic styles for the V6to 89 it used the mercury switch like the v4 1990 to 1995 2.6L v6 used the trim sender all 3.1 and 3.3 used a pulser coil signal to allow normal oil transfer and 2.6L from 1996 uses the same system as 3.1l.
I watched a tech trouble shoot a 97 150 for 6 hours and replace an ECU cause he did not know that you cannot jumper the pump on blue white wire with the key on and make the system transfer.
