89 mercruiser 7.4 454 v8 with bravo 1, bogging down

[combs4993]

I have recently purchased a 89 powerplay spectra 222 with a 7.4 mercruiser in it, originally it was overheating, but was able to solve that problem, now it is bogging down or sounds like its out of gas, with it in gear I can get up to 3k rpm but if I pin the throttle it breaks up and sounds like it wants to die out.
Now heres the weird thing it doesn't do the with it out over gear I can rev it to high heaven and it be fine

Also the batteries aren't charging due to a loose alternator belt I think since I took it off to pull the sea water pump, I might not have got it tight enough, I was wondering if this would also cause this problem any tips or insight as to why it won't rev past 3k while in but would be greatly appreciated as I am just getting into the boating world recently

Sorry for the long post

 

[alldodge]

Howdy

You have several possible issues.

Reving in neutral tells us nothing about the motor.

Not getting over 3K rpm in gear is either, timing, fuel and could be voltage but in most cases, low voltage would cause the motor to miss

Did the boat ever go above 3k rpm while in gear, or in other words did you do a test ride prior to buying?

What is the motor serial number?

 

[Bondo]

now it is bogging down or sounds like its out of gas, with it in gear I can get up to 3k rpm but if I pin the throttle it breaks up and sounds like it wants to die out.
Now heres the weird thing it doesn't do the with it out over gear I can rev it to high heaven and it be fine

Ayuh,...... Welcome Aboard,....... It probably is runnin' outa gas,.... Without a load, it needs virtually no gas,...

Under load, it needs Lotsa gas,...

Check the Contents of the fuel filter for clues,......

 

[Scott Danforth]

your motor would rev to destruction in neutral only running on 2 cylinders.

as Bondo stated, only a few drops of fuel would be needed.

when the motor is under load, it is guzzling fuel by the gallons

look to your fuel system.
do a fuel pressure check
check your anti-siphon valve
check the contents of your fuel filter for pure fuel
if needed, rebuild your carb.

 

[combs4993]

Howdy

You have several possible issues.

Reving in neutral tells us nothing about the motor.

Not getting over 3K rpm in gear is either, timing, fuel and could be voltage but in most cases, low voltage would cause the motor to miss

Did the boat ever go above 3k rpm while in gear, or in other words did you do a test ride prior to buying?

What is the motor serial number?

Serial number is 0C536204

and no no test ride before purchase it was winterized for a year before I got it and shrink wrapped i knew It was going to need some work

I have A new fuel filter and fuel pump, a new distributor cap and rotor, as well as new plugs and wires on the way already

im going to check the alternator to make sure the belt is tight as well because i put a new circulation pump on and may not have gotten the belt tight enough as its not charging the batteries like it was before i did any work to it

Thanks for the info guys

 

[alldodge]

Suggest a compression test. This will tell if the motor is healthy enough to supply the power needed

Measure the output of the alternator running around 1500 rpms, should be 14.5V or so

 

[tpenfield]

:welcome: to iBoats . . .

If the engine runs great in neutral, then just run it in neutral . .

As stated, running an engine in neutral proves nothing (nothing) .

I'd go with the compression test and a deep cleaning of the carburetor, check the timing. Then see where you are at.

 

[combs4993]

Would the trim have anything to do with this issue as well, I have a leak in one of the hydraulic lines going from the trim pump to the outdrive so the outdrive doesn't stay up when out of the water to tow home so we strap it up but would that have anything to do with it

 

[tpenfield]

Would the trim have anything to do with this issue as well? I have a leak in one of the hydraulic lines going from the trim pump to the outdrive so the outdrive doesn't stay up when out of the water to tow home. So we strap it up, but would that have anything to do with it :noidea:

No . . .