Oil Pressure

[rwdenis]

I bought a 2001 21V Fox Racing (MerCruser 350) earlier this year from a dealer and the engine was tuned and checked out. I noticed last week that I needed to top up the oil (with a quart of Synthetic 10W30). This was after 80 hours of use since the last oil change (400 hours total on the boat). Is this normal? At what point would I change the oil? I normally change it (or, rather, have oil changed at the marina) once a season. Is this sufficient?

Last week, after three hours of boarding with a full boat, followed by a barefooting run at 45 mph, I noticed that the engine temperature was relatively high (a bit higher than usual - that's to be expected with increased strain on the engine) and the oil pressure was relatively low (close to the "red section" of the oil pressure meter - reading taken while running the boat at half throttle). Is this cause for concern (the oil pressure)? What does low oil pressure mean? Sorry, but I know little about engines.

One last note, I wasn't able to check the oil pressure or the oil level afterwards as it was late Sunday and we were leaving the boat to get back home...

Thanks!

[dogbert]

Your higher than normal engine temp could be a sign that your impeller is failing. If you haven't replaced it in the last 2 years, it's time. Higher than normal engine temperature could cause you to burn oil as well.

The oil pressure could be a sensor or an indication of bigger problems. I'd have it checked out by a mechanic.

[spharis]

Also keep in mind that small block Chevy's burn oil. I don't think I have ever had a rig over 300ci that didn't burn a little oil.

[rwdenis]

I'll check it (the oil pressure) out when I get back to the cottage this weekend. This is pretty much our second to last weekend (the water is already 65 degrees Fahrenheit - it'll be in the 50's before you know it - and then there will be no risk of overheating - just kidding) so I'll take my chances. I will have the impeller replaced at the end of the season but I believe that the slightly hotter temperature was merely a function of barefooting at full throttle with a full boat. I usually keep my eye on this (I once had problem with an I/O (the intake line for the cooling water was blocked with "something") and hadn't noticed anything strange until I was parking the boat. I'll report back.

[dogbert]

Originally posted by rwdenis
I'll check it (the oil pressure) out when I get back to the cottage this weekend. This is pretty much our second to last weekend (the water is already 65 degrees Fahrenheit - it'll be in the 50's before you know it - and then there will be no risk of overheating - just kidding) so I'll take my chances. I will have the impeller replaced at the end of the season but I believe that the slightly hotter temperature was merely a function of barefooting at full throttle with a full boat. I usually keep my eye on this (I once had problem with an I/O (the intake line for the cooling water was blocked with "something") and hadn't noticed anything strange until I was parking the boat. I'll report back.

My boat never runs hotter at full throttle. I have the same engine and pretty much the same boat, except it's a couple of years older. Marine engines are designed to run at cooler temperatures than a car or truck engine.

[chpthril]

I would go after the hi engine temp first. As the engine temp goes up, the oil thins out, which results in lower than normal pressure.

Also, pull the dip-stick out and smell it. It should stink, but not smell like gas. Also rub some between your fingers, evan dirty and used, it should feel slick like new oil does.

[FIC]

We reccomend every 50 hrs. or 6 months on oil changes do to the fact that a marine engine is subject to extreme use and condesation getting into the oil .Dom@ Fortes Inboard Connection .