Is it normal for RPM's to suffer when driving into the wind?

[wingmastr23]

Pretty much sums it up......I was boating in some 17-20 knot wind and my RPM's dropped by atleast 600....it was insane!

Is it normal? Or is it a sign of another issue?

 

[mkast]

Re: Is it normal for RPM's to suffer when driving into the wind?

Is it normal?

Yes.
Put six adults in your boat, watch what happens.

 

[Steve91T]

Re: Is it normal for RPM's to suffer when driving into the wind?

That seems like a bit much, but aerodynamics make a difference. Especially if your boat is draggy. I had an old 89 Jeep Cherokee (I miss that thing. It would pull a boat, just wouldn't stop it). One day I was driving down the highway at 70 MPH. I was damn near WOT to maintain speed! I'm thinking, what's wrong? Then I realize I had nearly a 30 MPH head wind! So my poor Jeep thought it was doing 100 MPH.

As far as your boat goes, do you have a speedometer? What kind of speed were you doing? What was the difference in speed? If you really had a drop of 600 RPM, my opinion is that either you were boating in a hurricane, or it was by chance that something else was going on.

Steve

 

[wingmastr23]

Re: Is it normal for RPM's to suffer when driving into the wind?

That seems like a bit much, but aerodynamics make a difference. Especially if your boat is draggy. I had an old 89 Jeep Cherokee (I miss that thing. It would pull a boat, just wouldn't stop it). One day I was driving down the highway at 70 MPH. I was damn near WOT to maintain speed! I'm thinking, what's wrong? Then I realize I had nearly a 30 MPH head wind! So my poor Jeep thought it was doing 100 MPH.

As far as your boat goes, do you have a speedometer? What kind of speed were you doing? What was the difference in speed? If you really had a drop of 600 RPM, my opinion is that either you were boating in a hurricane, or it was by chance that something else was going on.

Steve

My boat typically tops out around 40mph - I was doing like 25-30mph tops....my RPM's are typically around 4400 (Mercruiser 3.0l) and I was barely getting to 3800rpm's at WOT.

 

[jimbo_jwc]

Re: Is it normal for RPM's to suffer when driving into the wind?

My old boat the rpm's would actually increase into the wind . I guess the dual cathedral should have been named gull wings instead .

 

[LippCJ7]

Re: Is it normal for RPM's to suffer when driving into the wind?

oh yeah time for a big block!!!

 

[5150abf]

Re: Is it normal for RPM's to suffer when driving into the wind?

Next time turn around and run with the wind, if it is still bogging down you have a problem, but yes it shouldn't run the same because there is more load on the boat.

I would suspect you are at the top or just over propped and the extra resistance by the wind caused the drop but unless it is constantly windy I wouldn't change anything.

 

[Mischief Managed]

Re: Is it normal for RPM's to suffer when driving into the wind?

It was probably the waves that the wind kicked up that slowed you down. That said, those same waves can stir up crud in your fuel tank and clog the fuel filter starving the engine for fuel, or exacerbate a dodgy electrical connection problem in the ignition.

 

[steelespike]

Re: Is it normal for RPM's to suffer when driving into the wind?

Wind and waves slow the boat.The wave action tends to push the bow up making it harder to stay on ideal plane.You may do a little better if you trim in.

 

[ziggy]

Re: Is it normal for RPM's to suffer when driving into the wind?

large wind always slow my rpms down too. mostly because i have to throttle back for conditions. least that's been my experience...

 

[wingmastr23]

Re: Is it normal for RPM's to suffer when driving into the wind?

Next time turn around and run with the wind, if it is still bogging down you have a problem, but yes it shouldn't run the same because there is more load on the boat.

I would suspect you are at the top or just over propped and the extra resistance by the wind caused the drop but unless it is constantly windy I wouldn't change anything.

I think you hit the nail on the head.......I have been thinking that I have been over propped since I bought the boat - I am running a 13.75 x 21 on a Mercruiser 3.0l - pushing a 19' fish n ski......Just ordered a new prop last night....went with a 14x19 - and if that doesn't work, gonna drop to a 14x17.

5150abf - I did turn it around and it would work fine.....I guess I just didn't think the wind should affect it so drastically.