oil pressure on 200 I4 Yamaha

[captnick]

My oil pressure shows in the middle when idling before a trip. After a 20 mile cruise and taking it out of gear it's one bar down from where it was. I've checked it cold and it shows in the safe zone on the stick. Is this due to the oil getting hotter and thus shows lower pressure? Anyone else experience this? I put many miles on it running 25-26 knots at 4100-4300 rpms. Do they use oil? My 225F never seemed to use oil between changes. My oil was changed int the fall by Yamaha tech.

 

[warthog5]

I've never seen a Oil Pressure gauge on a outboard.

 

[Brent]

From WiKi

Sufficient oil pressure ensures that the metal of the rotating shaft (journal) and the bearing shell can never touch, and wear is therefore confined to initial start-up and shutdown. The oil pressure, combined with the rotation of the shaft, also hydrodynamically centers the journal in its shell and cools the bearings. Such a bearing is known as a fluid bearing.

Oil pressure is higher when the engine is cold due to the increased viscosity of the oil, and also increases with engine speed until the relief valve in the oil pump opens to divert excess flow. Oil pressure is lowest under hot idling conditions, and the minimum pressure allowed by the manufacturer's tolerances is usually given at this point. Excessive oil pressure may indicate a blocked filter, blocked oil gallery or the wrong grade of oil. Low oil pressure indicates worn bearings or a broken oil pump.


Sent from my iPad using Tapatalk

 

[Brent]

Curious

How often do you change oil and oil weight? Thicker oils like 20w50 flow slowly until hot. Regular oil and filter changes are important. Are you using Yamaha oil and filters?


Sent from my iPad using Tapatalk

 

[grouperjim]

Is this due to the oil getting hotter and thus shows lower pressure? Anyone else experience this?

Yes. normal



FWIW if you want to monitor water pressure as well there is an unused port labelled "W" on the back of the motor. It can be a nice indicator showing the health of your impeller. All you need is an inexpensive sensor to replace the bolt that plugs the hole. Then snap the sensor into the adjacent wiring harness.......15 minute job.

 

[captnick]

I've never seen a Oil Pressure gauge on a outboard.

The 6YC unit shows oil pressure and water pressure. It's a pretty slick unit. I guess dropping down one bar after running an hour at 4000+RPMs and dropping to idle is normal. I just happened to notice it the past couple trips and figured I'd run it by you folks. Thanks. Going to the Flemish Cap(not quite) sometime in the next two days. Now I can go worry free.

 

[captnick]

Curious

How often do you change oil and oil weight? Thicker oils like 20w50 flow slowly until hot. Regular oil and filter changes are important. Are you using Yamaha oil and filters?


Sent from my iPad using Tapatalk

I have the oil/filter changed at the end of season when they "winterize" it. I usually don't put more than 125 hrs a season. They're certified Yamaha so I assume they use Yamaha spec.

 

[Brent]

Thanks


Sent from my iPad using Tapatalk

 

[GoodChance]

My F300 has an NMEA 2000 oil pressure sensor that feeds data to my multi-function display. On normal conditions, after 10 minutes of operation, the pressure reads 71-72psi and remains there for hours at cruising speeds of 3300-4000 rpm. Even if I "kick-it-up" to 4500-5000 rpm, the oil pressure remains constant and unchanged. But as soon as I come off plane, the pressure drops to 50-60psi. All of this said, the oil pressure reads 80psi during the first 10 minutes of initial operation on cold oil. The term "cold oil" is a a bit of a misnomer since I'm in Florida and "cold" is 75 degrees.

All of this said, the Yamaha Command Link Gauges indicate that the oil pressure is always "normal range". At 70 psi, the CL says that I am at the middle bar. At 80 psi, I'm 1 bar high of the middle but still in the acceptable range.