Am i pushing her to hard?

[mrmushroomman]

I've got a 1995 18.6 ft sea ray with the 4.3lx with 4brl weber carb. It has a 23 pitch aluminum prop. When i am at wot the rpms are close to 5000 rpms and speed is at about 50mph. I know that the recommended range is 4400-4800. Am i running to hard at wot with this prop and if so should i go to a 24 pitch. I was very surprised to see the 23 pitch put me at 5000 rpms when the factory manual says boat came stock with a 21 pitch. I definitly like having the top end speed over the whole shot because we don't do many watersports. I don't want to strain the motor running it harder than it should be run. Any advice is greatly appreciated.

 

[KM2]

Re: Am i pushing her to hard?

Your right it's surprising to see you turn 5k witha 23in prop. I have a similar boat & motor and I can't do that.

Any engine modifications, drive changes (gearing)??

 

[mrmushroomman]

Re: Am i pushing her to hard?

No changes or add ons except it has the 4brl carb. I'm affraid if i change the pitch to much that it will affect rpms. With wot at 5000 and the top end rpm range calling for 4800rpms on the high side it's running pretty close. I'm just wondering if i shouldn't run her to 5000rpm and hold it back a little bit around the 4700-4800 range.

 

[haskindm]

Re: Am i pushing her to hard?

You should never run a motor faster than the recommended "red-line" for RPM. Either re-prop to get down to the recommended RPM or back off the throttle to keep from over-revving. You may also want to check the accuracy of your tach to make sure you are actually achieving the RPM's indicated.

 

[nlain]

Re: Am i pushing her to hard?

I would not run wot for long it is not good for the engine. I have a 2004 SeaRay 185Sport, 4.3L 2bbl Alpha with 23 P prop, I have seen 49 mph per gps at about 5100. If you back the rpm down to about 3500 you will go a lot further on a gallon of gas also.

 

[Willyclay]

Re: Am i pushing her to hard?

What gear ratio do you have in the outdrive?

 

[mrmushroomman]

Re: Am i pushing her to hard?

Gear ratio is 1.84. I think i will just buy another prop and see if that helps and keep the 23pitch for a spare.

 

[stevens]

Re: Am i pushing her to hard?

... or try a same pitch SS prop, which would usually lower RPMs by 1-200 relative to an alu prop, putting you exactly where you should be and probably giving you a bit better speed as well.

(..but I'd verify that tach first...)

 

[Willyclay]

Re: Am i pushing her to hard?

I will interested to see your next post if you replace the prop. My son has a 1995 Ebbtide 192SE with 4.3LX engine ( 4 barrel Weber) and 1.84 gear ratio. He has a 19P aluminum prop but the revs are 4,800 and speed is just under 50MPH on speedometer. His NADA dry weight is 2,600lbs. Good luck!

 

[mrmushroomman]

Re: Am i pushing her to hard?

I will keep you updated willyclay. It might be a while before i buy a different prop because all my money is going into the gas tank right now. I will definitly stay out of the secondaries on the 4brl when gas prices are $4.30gal. If he has a 19 pitch prop and is at 4800rpm at wot sounds like he is right where he should be. I might try a 21 pitch which is what Sea Rays web site says the boat came with when new.

 

[freddyray21]

Re: Am i pushing her to hard?

while they are designed to have a max rpm of xxxx in my opinion it is not good to run them at that for long periods of time. If you back off it will get better mileage. Mine had a max rpm of 4300 and it will do that fine, but I tend to run in the 3400 range and cruise just fine.

 

[Willyclay]

Re: Am i pushing her to hard?

You got me thinking about my tach. Next time out, I will take my hand-held GPS and a portable tach for verification of our speed and RPM's. Will post if different. Good luck with yours.

 

[Johnny_Law]

Re: Am i pushing her to hard?

Not sure of your drive ratio, but are you sure of the accuracy of your tachometer?