Oil temp sensor?
05-17-2011 | 02:23 PM
#12
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From: So Cal
05-17-2011 | 04:00 PM
#13
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From: NY
It's actually an oil pressure switch... for the choke circuit. It doesn't allow voltage to the choke coil unless the engine is running. That way if the key is left on without the engine running, the choke coil is not inadvertently warming up and opening the choke without the engine running.
In a factory Merc harness, the wire for the oil temp sender is dark brown, or dark brown with a white tracer. As Eddie stated, 3/8 NPT in the block, just above the filter pad, is the best placement for the sender.
08-23-2018 | 11:04 AM
#15
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From: Fort Worth TX
Oil Temp Sender
The best place to read oil temp in a Gen VI block is the 3/8" NPT port just above the oil filter pad (where the oil filter would be in a car). The pressure sender will be there, so you will have to move it. You can put it in the port just above the bell housing, the filter housing, or in the 1/4" npt port on the side of the block just above the oil pan rail near the front. You want the oil temp sender in the flow of oil, not a dead end passage that has stagnate oil. The port I mentioned is the absolute best place. The pressure sender can go anywhere, even if it is in a dead end passage. Pressure is pressure. You want to know the temp of the oil that is going in the engine. Good luck. Give me a shout if I can help.
Eddie
Eddie
Thanks
08-23-2018 | 05:23 PM
#16
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I'm having same issue. Just switched from a 496HO to a 500efi and now my oil temp gauges don't work...Actually can't recall if they worked on the 496's either. Any advice? The gauges are wired as I put new gauges in 2yrs ago. I'm guessing it's the sensor wire or the senders aren't in the right location to read correctly. My boat runs 155 degrees on water temp so oil should be within 10-20 degrees I would imagine. It doesn't even move on the gauge.
08-23-2018 | 08:26 PM
#18
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From: Grand Rapids, MI
After the cooler. This is the temp that the oil is before the oil goes to your bearings, the important temp. If you want to have one in the pan or before the cooler to see how hot your oil gets, do this as a secondary sender and just use a toggle switch to toggle between senders. This will tell you how well your cooling system is working.
08-24-2018 | 05:12 AM
#19
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From: Olmsted Falls,Ohio Marblehead,Oh
My 87 Gun has them in the pans, I prefer to read after cooler but in this case I still don't see more then 180 IN PAN! (hot side) at them temps I am not worried, so I have not moved them yet, new gauges and senders and verified with temp laser, so look down by your pans especially if Hawk powered with GIL pans, very common place, wire is single Brown.
