Is 2000 RPM on muffs okay?

[banderberg]

I need to fine tune my new Faria tach and they said I need to turn the POT screw at idle and also at mid throttle.

Is there any risk to running the engine on muffs at 2000 RPM for a few minutes? Just need to check RPMs with my digital tach and then adjust the POT screw to match.

It's a 1990 3.0L

 

[Rick Stephens]

I need to fine tune my new Faria tach and they said I need to turn the POT screw at idle and also at mid throttle.

Is there any risk to running the engine on muffs at 2000 RPM for a few minutes? Just need to check RPMs with my digital tach and then adjust the POT screw to match.

It's a 1990 3.0L

I'd do it in a second as long as I had plenty of water flow from my spigot. The risk is the impeller will pull more water than the hose can provide and you end up with the hose sucked flat. Next is the impeller is toast.

I believe that Mercruiser states 1500 RPM max on muffs because of that possibility. If you have a big enough hose and enough flow, 2k isn't going to be a problem.

 

[dubs283]

Is there any risk to running the engine on muffs at 2000 RPM for a few minutes?

No

You'll be fine. Best test is to set the tach engine running on muffs. Then compare with a shop tach first on muffs then in the water, full rpm range