1985boat shevrolet 350 oil presher guage peged.replased sending unit

Is the gauge reading degrees or PSI?......If the wire going to the sending unit is shorted to ground, it will peg the gauge.......

you need a new sending unit and stop unplugging things when there is power to them,you can ruin it

Sounds like a grounded wire. Most senders change resistance to the ground circuit of the gauge. If it pegs there is no resistance to ground and probably a shorted wire.

Sounds like a bad oil pressure sending unit.

Try unplugging it and see if the gauge drops to zero. If it does than replacing the oil pressure sending unit will most likely fix your problem.

It is not easy to see or get at but you can find it on the back side of the engine on the drivers side, kind of in between the valve cover and the intake plenum

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

remove sending unit and install mechanical gauge to see oil pressure psi if psi reads ok- change sending unit again if psi to low less then 6 replace oil pump och.

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down beside oil filter

You probably need a oil pressure sending unit it is located at the back of the engine and is a high failure

could be the oil sending unit

All you have to do is replace your oil pressure sending unit.It`s in the rear of the motor by the left head.This is the drivers side.You need a special socket to remove the sending unit.Good luck.

it sounds like your oil pressure sending unit may be plugged by whatever took your pressure down to 5-8 psi the first time. this is extremely low pressure as i am sure you know but at 30 psi your light should go off i would replace the sending unit if your oil pressure is holding 30