3.0 Litre Mercruiser Power

[79calglass]

Hello,

I have an 18 foot bowrider with a 3.0l Mercruiser. The boat has really slow take offs. I can throttle slowly and accelerate up to plane. But if I throttle all the way down, nothing happens, the rpm does not increase. The only way to get to plane is to slowly increase the throttle.

Is this normal, or should there be more power or rpm increase on full throttle take offs?

Thanks.

 

[Scott Danforth]

Re: 3.0 Litre Mercruiser Power

sounds like you have carb issues. I would look at the accelerator pump first.

 

[Bondo]

Re: 3.0 Litre Mercruiser Power

sounds like you have carb issues. I would look at the accelerator pump first.

Ayuh,... Agreed,... A Rebuild, 'n new acc. pump might do it...

 

[79calglass]

Re: 3.0 Litre Mercruiser Power

Thanks. I've read on other forums that I should have 2 streams going into the carb. I removed the throttle cable and pumped and I see2 solid streams flow in.

Is there a good forum on how to do a carb clean on the 3.0? It's a 2007.

 

[86 century]

Re: 3.0 Litre Mercruiser Power

If you have to good streams of fuel coming out the pump is working.

Check the linkage make sure it starts spraying off of idle.

 

[achris]

Re: 3.0 Litre Mercruiser Power

...Is this normal, or should there be more power or rpm increase on full throttle take offs?...

No, it's not normal. But before we can start chasing down a problem we need to know a lot more about the engine and it's history.

Let's start with either the engine year, or (better) the engine serial number.

Some history. Has the boat always been doing this? Has it come on slowly and gotten worst? Did the problem suddenly appear? When was the last FULL service? What rpm does it make at full throttle?

Do a compression test and post the result. Check the ignition system and make sure it's working fully and correctly. Check for a nice healthy fat blue spark across an air gap of about 1/2" from each plug lead to the engine block. Check the plug gaps, the points dwell and the timing, and check that the timing is advancing correctly...

Once the ignition system is checked and given a clean bill of health, then turn your attention to the fuel system....

Chris......