getting faster as it gets older

South lake

Well-known member
Joined
Dec 8, 2011
Messages
222
Fluid Motion Model
C-24 C
Hello Tugnuts. It's been awhile since I made a post but it's summer in the Midwest and my time is best spent on my 2010 Ranger Tug R25 Classic Cabin. Just wanted to make a comment, an observation, and a question for the experts on the forum.

This spring when I launched the boat in March I noticed what looked like white smoke and I got pretty concerned. Now the Yanmar 150 purred like a kitten and ran fine but I thought something had to be wrong. The guys that take care of my boat are 150 miles away on Lake Erie so I called them and they said they thought it was just steam from the exhaust because the lake water was still cold. Anyone who knows me knows I'm no mechanic so I was still worried enough that I hauled the boat up to them and they checked it out in person. Still thought it was fine. I won't go into all the other checks I did but they must have been right because the white "smoke" went away after a few weeks as the weather warmed, and the boat has run as good as ever all season.

But... I have noticed something different. Always in the past when I went WOT, the tach would stop at 4,000 rpm's. Boat would buzz along at just at 19 or 20 mph. I usually cruise around my lake at about 1,730 rpm's which gives me a speed of 6.5 mph and burns a gallon an hour of diesel. But every now and then I open it up for a bit. Well this year I noticed for the first time that when I pushed the throttle all the way the tach showed 4,100 rpm's. And I'm not sure why or if that would present a problem. When I noticed that was happening I made a point of keeping the throttle back so it doesn't go over 4,000.

Now, the boat has 570 hours on the engine. I assume with wear perhaps changes in top rpm's occur but frankly I have no idea. So as with all things unknown, I pose it in questions on Tugnuts. Is this normal? Would it hurt to run the boat at 4,100 rpm's? Should I even care?

Appreciate any thoughts those who have an opinion can share.

Finally though I do have to say there is no finer boat than a Ranger Tug R25! Bought it new and still love it better than any boat I ever had.
 
My boat has white smoke too when it's a bit colder outside, we noticed this on our last trip, in the morning when it is colder... But all the other days when it was warmer no smoke.
 
Weight, boat attitude, current, wind and water type can affect RPM 's. I sometimes get over the 4,000 rpm at WOT. I just stay below it and not worry about it.
 
Ditto! We vary from 3850 to 4050 RPM at WOT depending on the conditions.
 
Smell the smoke (just sniff it, don't ingest it 🙂). If it has a sweetish smell it is an anti-freeze leak. If it has little or no smell it is likely steam. If it has kind of an acidy/smoky smell it may be unburnt fuel, but I've found that the Yanmars do smoke white with an acidy/smoky smell when cool. If the smell is excessively strong one way or the other (too sweet or too acidy) you likely have an issue.
 
Back
Top