We are nearing the end of the boating season, but I’d sure like to get in a few more excursions. Things aren’t looking good, though. Any ideas would be appreciated.
I have a pontoon boat with a 90 HP outboard. There is an oil tank on the boat. As I understand it, the motor pulls oil as needed. I fill the tank usually every other time that I fill the gas tank.
This past Sunday we were on the water. I started with a full oil tank, which I figured would last the remainder of the season. However, a warning alarm went off for low oil near the end of the day. I opened a gallon jug of oil and filled the tank. We were headed in anyway. As I approached the marina, the low oil alarm went off again. I poured what oil I had left and made it to my slip.
There was no smoke, the motor ran smoothly, etc.
Any thoughts on what would cause this? Any easy fixes? Realistically, if this problem entails pulling the boat out of the water, my season is over.
Is the oil tank situated in such a way that you can visually confirm how much is in there? What I’m getting at is was the tank, indeed, low on oil when it warned you to add more?
Leaking or overfeeding. You’d probably notice a smoky exhaust if it was overfeeding the oil. If it’s leaking oil into you could get fined for that if it’s noticed, depends where you are and who’s watching.
I’m not familiar with Yamaha outboard oil injector systems but it seems to me that you could disconnect the oil tank and manually mix the oil with the gas. Probably 50 to 1. Ask a Yamaha dealer.
I’m familiar with Evinrude engines and that used to be a common fix. I knew boaters who disconnected the oil injector on brand new engines because they were concerned about an oil injector failure ruining their 5K-12K motors.
At this point, I’m suspecting a cracked and leaking oil feed hose near or where it enters the mechanical part of the engine. Did you remove the cowl to see if there’s oil being puked up under there? If not puking, it could be tricking down the oversplash/overflow hole in the bottom platform of that upper housing.
Also, yes… premixing the fuel + oil would let you finish out the season. Confirm with the marina or other *expert *about the ratio.
As you already know. A gallon of oil just doesn’t disappear when you’re boating. If you weren’t putting out a huge smoke trail or a huge oil slick then that oil is still hanging out where it shouldn’t. I’d pull the boat out before messing around with it and I’d have a bunch of the oil absorbent pads when you do it. The moment you tilt the motor, you could have a huge mess on your hands.
The mix depends on the type of oil used. Normal mineral 2-stroke oil is 25:1. However if you have the special synthetic 2-stroke mix then 50:1 and this is what most modern 2-stroke engines are happy with.
I use Stihl chainsaws and am OCD about the oil mix - 50:1 synthetic.
I know a couple of guys who have stopped using the oil feed and just mix their gas so they don’t have to worry about it. You can buy little bottles of oil made for just one gallon of gas to make it easy to do the mix, that is if you have a small tank. I don’t think you want to open 40 little bottles when you fill your tank.
I was riding my Yamaha RZ-350 from Vegas to Tahoe, and out what was the middle of nowhere, the “Red Light of Death” came on (low oil level) and I was shitting bricks.
Then, came firing around a corner in Wellington, and there is a tractor dealer with a big old “Yamalube” sign out front!
There’s no bilge on a pontoon boat to collect spilled fluids, so we can narrow this to two possibilities. It’s being burned, or leaking.
You said no smoke is visible, so the next step is to run the engine in a calm place like your slip for 10-15 minutes. Then shut down and examine the water around your boat for oil. Oil is pretty obvious in still water (you may have to move around the dock to get the sun just right). If you find evidence of oil, you’ve proven a leak somewhere between the tank and the intake for the cylinders. This probably won’t require a haul-out. I’d pull the cover from the engine and look around for evidence there too.
I have a Mercury 2 stroke. The previous owner disconnected the auto oiler. He said that the pump had a plastic gear that commonly failed and no warning would be given. I mix at 50:1 (really only necessary at wide open throttle) with TCW3 outboard oil. Its messy and a bit of a pain but its not worth the expense to replace the auto oiler. Any brand will do as long as its TCW3 type oil. I buy it buy the gallon at Autozone for around $20.
Well, I spoke with Yamaha people about mixing oil/gas and calculated that to get 50:1 I could add a pint to every 6 gallons. I was unsure about the size of my gas tank, but it was 1/4 full.
I decided to pull the cowling before committing to anything. Turns out the small tank under the cowling has a ~4 inch long rubber plug and it was dislodged about halfway out of place. I pushed it into place, it snapped securely and I ran the boat all day Sunday.
In retrospect, I should have done this right away. I never thought the problem could be that simple.:smack:
No, not ideal, but fun as hell. Especially once I got to Tahoe.