How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Tan Your Own Question
Tan, MerCruiser Certified Technician
Category: Boat
Satisfied Customers: 11077
Experience:  40 yrs. experience with complete engine repairs both inboard/outboard and MerCruiser Certified Technician.
Type Your Boat Question Here...
Tan is online now
A new question is answered every 9 seconds

I have a 2005 SeaRay 185 Sport with a Mercruiser 4.3

Customer Question

Good morning! I have a 2005 SeaRay 185 Sport with a Mercruiser 4.3 engine...I noticed last time I was out on the water that my oil pressure gauge was pegged. After looking things over, I now see that there must be a short of some sort as the gauge pegs the minute you turn the key, engine off.
JA: Sometimes things that you think will be really complicated end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Is there anything else the Marine Mechanic should be aware of?
Customer: When I removed the sender wire from the pressure sender, the gauge stays at zero, even when I turn the key. I have not yet tested the resistance on the oil sender, but at this point, I figure I may have a bad sender. Is that common?
Submitted: 1 year ago.
Category: Boat
Expert:  Tan replied 1 year ago.

Hello. My name is Tan.

Yes oil senders are a common failure. Disconnecting the send wire and the gauge not pegging is an indicator the sender is bad or the sender wire is shorted to ground. Do this test disconnect the sender wire from the gauge and the sender and check for shorts to ground with your ohm meter. You should read no continuity open circuit. If you get a reading look for a spot on the wire on engine that may be rubber through causing a path to ground. This is highly unlikely you have a short but I never assume anything. If wire checks good then test the sender for a path to ground. Since the gauge pegs this will be the issue.

Post back with questions and findings. Thank you....Tan