Engine Speed

[spicerak]

Ok I Have A Evinrude 150 1989 Xp I Am About4500 Rpms And Going 30 Mph Is That Ok I Have Talked To People And They Say They Are Doing About 40 These Are All From Gps Readings The Engine Is Running Fine Compession Is 90 All They Way Around What Do U Think

 

[wilde1j]

Re: Engine Speed

Your motor should be turning ~ 5800 @ WOT. Something's not right. Has it always been 4500? More info, pls.

 

[tashasdaddy]

Re: Engine Speed

agree, you need to check spark, and what do your plugs look like.

 

[spicerak]

Re: Engine Speed

Plugs Look Good I Did Have A 24 Pitch Prop Switched To A 21 It Aloud Me To Tweak And Get To 5000 Rpm And It Is Running A 100 Times Better How Fast Do U Think I Should Go With 5000 Rpm Thanks For Ur Help Too.also It Has A 40 Gallon Tank And When I Went Out It Was Me And A Friend That Were About 550 Pounds Does That Make Any Sence

 

[wilde1j]

Re: Engine Speed

Repeat, 5800 RPM. 5000 is not good, way too low. 500 to 600 lbs shouldn't make much difference with that motor. What boat? Forget about how fast ... way less important than getting the RPM's where they need to be.

 

[spicerak]

Re: Engine Speed

18 Ft Neptune Center Console 40 Gallon Tank 500 Pounds Of Fat *** Lol What U Think Thanks For The Help

 

[tashasdaddy]

Re: Engine Speed

as said, speed comes after proper set up. your motor to perform properly needs to turn 5500 -6000 rpm, 5800 is a happy medium. the reason for this is the engine runs cooler with the fuel we burn these days. running at the rpms you are running is lugging the motor, causing add than necessary wear.

 

[wilde1j]

Re: Engine Speed

Is cav plate buried @ WOT, or can you see it clearly w/o water on top? If it's covered up, start raising the motor a hole at a time until the cav plate is uncovered and the motor doesn't cavitate in turns @ WOT. You should pickup both speed and RPM's if the motor needs to be raised. Once you get the motor setup right, then experiment with props to get 5800 RPM.

BTW that's a light boat and a big motor. When you get it right, it should be in the 45 to 50 MPH area. My '85 140 HP Johnson moved a 19' Sea Ray over 40 NMPH.

 

[spicerak]

Re: Engine Speed

is that a gps scale and are u sure i should be 5500 and 6000 are u sure please tell me the truth

 

[tashasdaddy]

Re: Engine Speed

gps has nothing to do with this. getting your motor set up properly is more important, if you want it to last and service you well. why would anyone on here lie to you. the OEM manual said 4500-5500, that has since changed with the quality of the fuel we burn. you have been given the best advice available, it is your choice to use it.

 

[spicerak]

Re: Engine Speed

you are awesome thanks what is th plate ur talking about not sure what u mean.i have a manual jack plate should i lower it or rise it thanks again for all the help.i was drunk last night not sure what i was saying lol

 

[wilde1j]

Re: Engine Speed

you are awesome thanks what is th plate ur talking about not sure what u mean.i have a manual jack plate should i lower it or rise it thanks again for all the help.i was drunk last night not sure what i was saying lol

Read post #8

 

[spicerak]

Re: Engine Speed

ok what is a cav plat not sure what u mean nothing is in the water

 

[tashasdaddy]

Re: Engine Speed

the cav plate is the flat plat just above the propeller. it actually is the anti-cavatation plate.

 

[spicerak]

Re: Engine Speed

So Wot And Engine Tilted Up I Should See Cav Plate I Do Think Engine Is To Low I Have A Manual Jack Plate So Its Easy To Lift Where Should It Be When Im Wot. When Im Out Of The Water I Cant Put Engine All They Way Down Without Hitting Concrete I Should Raise It I Think Not Sure How Far Up Thanks For The Help

 

[iwombat]

Re: Engine Speed

If you've got a jack plate, probably the best thing to do is keep raising it up until the motor starts to cavitate in the corners. Then drop it back down until that goes away. Ideally the anti-cav plate should be even with to 2" above the keel of the boat when in the normal operating position. You may need to fiddle with the trim to find an optimal setting.

 

[spicerak]

Re: Engine Speed

So I Should Bring Engine Up To Where The Cav Plate Is Even With The Bottom Of My Boat Beacause It Is Way Below The Boat What Do U Think,also It Is A Manual Jack Plate So I Have To Be Out Of Water To Adjust It Thanks Fo The Help

 

[iwombat]

Re: Engine Speed

The lowest it should be is even with the bottom. Start there and see what happens.

 

[spicerak]

Re: Engine Speed

really so i am way to low do u think it will make me go faster and will it be easyer to steer because its kinda hard to steer when going fast

 

[iwombat]

Re: Engine Speed

Both of those, for sure.