1st run with my new (to me) boat was depressing

rainman1999

Seaman Apprentice
Joined
Nov 11, 2008
Messages
34
Well,my worst fear is happening:( I took my boat out for a test drive and I have mechanical issues,which is not my strong point) This is my situation; I have a 1999 240 cs Stingray with a 5.7L merc. alpha-one. I bought it used in October and fired it up on muffs to check that it ran. Yesterday was my first " on the water test" The boat hasn't been run since the 2007 season. I drained the gas, changed the oil/fiter, gearcase oil, water-separating filter in the fuel system, then added 10 gallons of fresh gas and launched her. The throttle/shift cable is very stiff. the oil pressure, engine temp, and volts are all good. I had to jiggle/pump the trottle lever to find a "sweet" spot before it would go, an aggressive acceleration isn't working (as to pull a skier). Once on plane I couldn't get more than 30mph and 3200rpms at wot. This boat should do around 50mph. I was thinking maybe she just needs to be run for a bit so I did a few loops and slowed, the shifted to reverse where it got stuck. I throttled forward and actually went bacwards! I finally got it to shift back into forward and just can't get her to go smooth and fast, something is definitely wrong:( A mechanic suggested my shift cable is corroded and a new one would solve both problems since the shifter and trottle are one) That would be great, but that sounds a little too easy. any mechanics have an opinion on that? I would appreciate any suggestions. I did put new bottom paint on also, except where my rollers are, I was going to keep her back on the trailer after my test run and get the bald spots.
 

JustJason

Vice Admiral
Joined
Aug 27, 2007
Messages
5,321
Re: 1st run with my new (to me) boat was depressing

as far as the stiff shifting goes. Yes its probably in the lower cable. You can disconnect the cables at the carb and the shift plate on the motor and work the shifter to make sure the boat side cables and the shifter itself are smooth.
As far as your running condition. When was the last time the boat had a full tune up??? Plugs, wires, cap rotor, ALL fuel filters/water sep filters...
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1st run with my new (to me) boat was depressing

Did you try trimming the drive up?
 

boatguya1

Chief Petty Officer
Joined
Apr 24, 2009
Messages
444
Re: 1st run with my new (to me) boat was depressing

I'm thinking shift cable work, carb rbld, tune up to make it run. Also Impeller, oil changes, drive r&r lube and align for maint purposes.

I have my doubts on 50MPH out of a 24' with a 5.7L?

Edit-missed that you already did the oils

James
 

Bondo

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Staff member
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Apr 17, 2002
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71,093
Re: 1st run with my new (to me) boat was depressing

I have my doubts on 50MPH out of a 24' with a 5.7L?

Ayuh,... I'd think low to mid-40s maybe...

I also agree, a lower Shift cable,+ Tune-Up will probably Fix it...
 

rainman1999

Seaman Apprentice
Joined
Nov 11, 2008
Messages
34
Re: 1st run with my new (to me) boat was depressing

Thanks for the responses fellas. Yes, I trimmed up, down, and in between. This is a 5.7L EFI merc, by the way. I was sceptical about the top end speed of this boat too. Thats what the stingray website brochure says it will do 51mph, to be exact. They claim its in the z-plane hull desighn, and its kind of light for that size boat; 5100 lbs. The dealership guy told me that stingray is actually conservative with thier top-end speed estimates, when I was buying parts I had expressed my opinion about a boat this size doing 50mph, and thats what he said. How many fuel filters are in this engine? I only changed the water-separater one. The engine actually sounds great when I throttle it up and down in neutral, the plug wires look fine, but I suppose that don't mean ****, right?
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1st run with my new (to me) boat was depressing

List of possible causes of low WOT (Wide Open Throttle) rpm.

In no particular order

Engine Won't Reach Operating RPM. Check

1. Fuel condition. Type and Octane possibly old fuel
2. Propeller pitch or diameter, damaged blades
3. Restricted fuel pickup tube or anti siphon valve Fuel System Test
4. Crankcase oil volume, high oil level can cause aerated oil and lifter collapse
5. Marine growth on hull and outdrive
6. Wrong gear ratio in outdrive
7. Restricted carburetor air intake (clogged flame arrestor)
8. Restricted exhaust system (broken exhaust shutters/flappers) in engine transom shield or drive
9. Poor cylinder compression Compression Test
10. Carburetor defective, or wrong type.
11. Fuel pump pressure and vacuum
12. Boat overloaded, improperly loaded, or improperly trimmed.
13. Engine Overheating
14. Engine timing and ignition system operation
15. Remote control cables and linkage for proper travel to open throttle plates fully.


Might also head up to the Adults Only sticky at the top of the page and download the OEM service manual for your engine and drive.
You need manual #24 for your engine. You WILL need the troubleshooting info for the EFI system.
 

QC

Supreme Mariner
Joined
Mar 22, 2005
Messages
22,783
Re: 1st run with my new (to me) boat was depressing

They never run again at test speeds . . . with that said, Stingrays are particularly efficient and get good top end numbers. So this is a 260 rated Throttle Body EFI? I had an earlier version of that system and it was absolutely trouble free. Good luck, stay after it and she'll be fine.

Oh, and for a "new to you" boat, this is not a bad first trip . . . ;)
 

JoLin

Vice Admiral
Joined
Aug 18, 2007
Messages
5,146
Re: 1st run with my new (to me) boat was depressing

Hi, Rainman-

Don't let it get you down. Sounds like you got a nice combo there, but you might very well spend most of this season getting things sorted out.

Start with the basice as mentioned above. Get the shift cable problem fixed and give the motor a good tune-up. I wouldn't tear into the throttle body yet. Change all the filters and see how it responds. You'll get there- the fact that it's running and didn't fail on you is a big plus. Oil pressure, temp and volts good- all are good signs.

Best of luck!
 
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