How long to safely run WOT?

[lilngineer]

I recently had a lower end failure on my 96 787. I was at a local shop picking up some parts and talking it over with the owner. He told me that you should never run WOT for more than short bursts of 15 seconds or else you will blow up your pistons.

This seems a bit over-cautious to me. Are the rotax 2-strokes really that fragile?

I previously owned a Sea Ray jet boat with a Mercury (Force) powerhead that I rebuilt and ran hard and WOT throttle often for several seasons with no issues.

So what's the consensus??

 

[kustomkarl]

Seadoo's have a rev limiter to keep you from over reving them or blowing them up. Running at wot won't hurt them unless it's constantly out of the water from wave jumping...but I bet the seadoo will hold up longer than your arms will. Your mechanic has no clue. 15 seconds...give me a break.

Karl

 

[lilngineer]

Just to clarify, he is not my mechanic. I am

I thought it was a bunch of BS also. I just happened to be talking to him while I was picking up a part.

Thanks for the reply Karl.

 

[RFoster130]

Seadoo's have a rev limiter to keep you from over reving them or blowing them up. Running at wot won't hurt them unless it's constantly out of the water from wave jumping...but I bet the seadoo will hold up longer than your arms will. Your mechanic has no clue. 15 seconds...give me a break.

Karl

Thats funny stuff

:rofl:

 

[captain scale]

Maybe he's thinking about a break in process! I run mine full speed on clam water for long durations, probably 10 minutes or more at a time when I'm cruising through the bay.

 

[Dr Honda]

As long as it’s not running lean… you can hold the throttle open for as long as you want. 7000-7500 RPM is low for a 2 stroke.

BUT… in a boat, I find dropping the throttle a little, once on a plane doesn’t drop the speed much, and saves on fuel. If I’m going “point to point” I set the throttle at about 6000-6200 rpm, and I only loose about 5 mph. But, when I’m playing… it’s at full throttle a lot.