Safe engine rev

I have a question regarding how fast is safe for a engine, I'm fairly new to boating having only ran a 6 hoarse Yamaha engine on my duck boat. Now I have a 140 in a 19 ft. Sting Ray. The boat is used for fishing mainly, but sometimes I feel the need to open her up. Last Saturday a big wind came up and I felt the need to get of the water fast, so I pulled the lines and took her up to 2500 rpms and she planned out nicely. My question is I know this boat will go much faster, but is it rough on the engine to run say at 3000. I have done this a few times and she goes like hell, but do hear what sounds like lifter noise, is this something to worry about. Does it hurt your boat engine to open her up when the conditions are right, or should this be avoided to save your engine life. She seems to cruise and plain out nicely at between 22-2500.

Re: Safe engine rev

You don't give any info on year, make, model, but the 140 engines typically have a WOT (Wide open throttle) rpm in the 4400 to 4800 rpm range.<br />Typical cruising is usually done in the 3200 to 3600 rpm range but may vary from boat to boat.<br />You should be able to run at WOT with no problems, but I wouldn't suggest it all the time. But it sure doesn't hurt to go WOT.<br /><br />I would sure get that tachometer checked for accuracy, I can't believe a 19 ft boat planing out nicely at only 22 to 2500 rpm with only a 4 cylinder engine.

Re: Safe engine rev

Sorrry about that. it's a 1982 Sting Ray Sport Fishing Cruser. Well my fish finder says I'm doing 17 mph at 2500 and 28mph at 3200 and she has plenty of throttle left. Don all I can say is that it comes out nice and flat at 2200 when the water is flat. I realy have never opened her up to WOT, kinda of afraid to hurt the engine.

Re: Safe engine rev

When I refered to year, make, and model, I was referring to the engine and drive, not the boat.<br />Mercruiser, Volvo, OMC.

Re: Safe engine rev

It's a 1982, 4.0 Merc Cruser 4 cyl I/O, what else?

Re: Safe engine rev

Hi everyone, I have a 1975 25' Sea Ray with a 233 merecruiser 351 Ford. I've searched everywhere to find out anything and everything about the boat and what I've found out to date is that it was a model Sea Ray made in 75 and mine by vin number is 23 or 28 of 43 madeand the following year around the same number were made. It's in pristine condition. I'd like to know what my WOT is for this boat. If anyone can help me I'd really appreciate it. and what propeller should I use, I'd like a little more speed and out of the hole shot, but mostly it will be used for cruising. Thanks