Pro Guide Basstracker (16') with a Mercury 9.9 Bigfoot engine barely hits 3000 RPM's.

[Basstracker16]

On 10/15/12- I bought a used Pro Guide Basstracker (16') with a Mercury 9.9 Bigfoot. The boat and engine is in great shape- barely used. I have taken the boat out a few times and noticed that at full speed my tachometer only gets to 3000 RPM's. That engine should hit 4500 or more. I have asked Mercury about this and they do not have an answer. However, one Tech suggested that I might have a problem with the Carb. He suggested drill out the brass cap and adjust the screw behind it. He said that the screw adjusts the RPM's. Does anyone have any idea where this screw is located? Or any info that relates to this issue.

The carb was taken off and cleaned on 10/15/12 by a Mercury mechanic. I checked everything about the engine and it runs great. No linkage problem. Prop is 10 X 7 and is in great condition. It idles great. It runs smooth. No funny sounds. Only problem- top end speed is lacking. RPM's barely hits 3000 but runs smooth.

I understand that this is a heavy boat to push with a 9.9 but the lakes around me have a 10hp restriction. I did not expect to plane but this is slow.

Ps- I have owned and repaired boats for over 30 years. I am not a boat mechanic but very handy. This problem got me stumped!

 

[Star]

Re: Pro Guide Basstracker (16') with a Mercury 9.9 Bigfoot engine barely hits 3000 RP

That brass plug and adjustment screw is on the carb near the throtle butterfly linkage. It is the idle adjustment only. so much for that tech!!! You will never push that hull to plane with a 9.9 (that is a four stroke, no) Is the basstracker aluminum? Is it a tiller or remote.
If you plow through the water with the nose in the air you have to move all the weight foward somehow. They make wings you can clip on the cavatation plate to make the prop more efficent and push the nose down. They do add some drag that eats up some of what you gain. A 15hp carb will bolt up to that motor but it is illeagle (EPA) to do that. Motor height and angle must be set right. That motor will turn 5200rpm. 3000rpm still sounds low with a 7 pitch Be sure that the bottom of the boat is smooth. I turn 4900 at 23mph with a alum 14'semi V and a 15hp 05 4 stroke! Every thing has been tweeked to get there! If you can get someone to check your compression
Put another 200 # pounds in it an it goes to 15mph. With a small motor everythingis more critical!!!! 3000 rpm on a bigfoot is not right!

 

[Basstracker16]

Re: Pro Guide Basstracker (16') with a Mercury 9.9 Bigfoot engine barely hits 3000 RP

That brass plug and adjustment screw is on the carb near the throtle butterfly linkage. It is the idle adjustment only. so much for that tech!!! You will never push that hull to plane with a 9.9 (that is a four stroke, no) Is the basstracker aluminum? Is it a tiller or remote.
If you plow through the water with the nose in the air you have to move all the weight foward somehow. They make wings you can clip on the cavatation plate to make the prop more efficent and push the nose down. They do add some drag that eats up some of what you gain. A 15hp carb will bolt up to that motor but it is illeagle (EPA) to do that. Motor height and angle must be set right. That motor will turn 5200rpm. 3000rpm still sounds low with a 7 pitch Be sure that the bottom of the boat is smooth. I turn 4900 at 23mph with a alum 14'semi V and a 15hp 05 4 stroke! Every thing has been tweeked to get there! If you can get someone to check your compression
Put another 200 # pounds in it an it goes to 15mph. With a small motor everythingis more critical!!!! 3000 rpm on a bigfoot is not right!

I am leaning towards a bad tach. I will try to have it tested first before changing anything. However, the Basstracker is alum and weighs around 1200 pounds so it will never plane but it does seem slow.

 

[Star]

Re: Pro Guide Basstracker (16') with a Mercury 9.9 Bigfoot engine barely hits 3000 RP

What does the tach read at idle? If it reads 400 rpm change the settings to read around 800 rpm. with the higher ratio of the bigfoot
gears that 10x7 prop should be turning 5400. I am running a 9.25x 11. SS Solas (very nice prop) The original prop was a 9x9.5 but it would let the rev limiter kick in when I was by myself. My 900# boat starts to plane out around 11 mph. I think that yours will plane out with a well setup motor and the larger 15hp carb and a good prop. Good Luck!