Pontoon Boat & Deck Boat Forum

My 2006 Fisher Freedom 221DLX has a MercCruiser 3.0 inboard/outboard. I bought it used and don't have the manual to identify which version of the MerCruiser (Alpha 1?) but it appears to be the 3.0 liter GM 4 cylinder with a 2 bbl carb.

Last summer I had trouble getting the engine to idle when shifter is in neutral. adjusted the idle screw and eventually got it to "idle" about 1500 rpm, which is too high for smooth forward/revers engagement. Boat was put up for the winter in November and not run until this weekend. Now I can crank but i have to advance the throttle well past idle to get the engine to stay running; below about 2500 rpm the engine slows down and stops. I don't have any issue cranking with the throttle advanced past idle. I don't see any evidence of engine running rich or anything like that. Engine runs fairly smoothly when it is running above 2500 rpm.

I am not a mechanic and I am not sure how to proceed to get this resolved. Any suggestions on what to look for?

Thanks in advance!

New Boat with a Yamaha Outboard?

Seriously, I'm guessing it's the carb.

Find someone who actually knows what a carb is. Sadly, many mechanics don't.

Did you use any type of fuel stabilizer when you laid it up ? Your carb most likely needs a good cleaning if you did not. Even so ,it sounds like a good cleaning of the carb would help.

In 2006, they were Alpha One Generation 2 drives. Great engine/drive package. Yes, you are in need of a carburetor rebuild. I had 2 boats with this engine and the only thing that goes bad on them is the carbs.

More than likely it is also a TKS carb. Very expensive to buy new at about $500-600. Sending them out to a rebuilder or rebuilding it yourself is the best bet.

I used to use http://flyingfishcarburetors.com/, they have fast turnaround and guarantee their work.

In 2010, Merc went to a fuel injected version of the 3.0, ending the carb problem.

One other thing, most people don't realize is there are 2 fuel filters on this engine. One is inside the carburetor fuel inlet and the other is in the bottom of them mechanical fuel pump. Very difficult to get to, and the 10mm bolt has a wire on it the prevent the bolt from loosening up. I've seen a bunch of people who have this engine and had never changed the pump filter until it began causing issues with fuel delivery.

i would start by using a fuel system cleaner like sea foam

I had one of the 140 hp Mercruisers, and they're not exactly the smoothest running engine coming off an idle. I agree that you probably need a carb. kit installed.

When I looked for a carb. kit, I found out my carb. was the same that Chevrolet used on a 1967 Impala 307 cubic inch engine. Your engine is probably different, but don't be surprised if the carb. is off an automobile prior to cars being fuel injected. If the carb. has a cast iron base, it can be rebuilt time and time again.

Just look for a good independent auto mechanic with white hair. The young kid mechanics don't have much experience on carbs since it's been 25 years since cars had carbs.

Rebuilding a carb. is not very difficult in reality. Last time I rebuilt the carb. on my 80 RX7, I only had 4 pieces left over and it still ran great.

I echo the stated above. A friend had a problem with the fuel filter at the pump but it was the opposite problem...it would idle and all ok but you couldn't run above about 1300 rpm without the motor cutting out.

I'd do a full carburetor clean and rebuild first. You could always go the band aid route and run heavy sea foam through a smaller tank to try and clean it but often times that just moves the gunk. Was the engine fogged when it was winterized? That makes a big difference with keeping everything from gunking up over the winter.

If it's a TKS carb, nothing automotive will retrofit. Merc started building their own 2 barrel carbs when Rochester would no longer make them. Sorry, it's only Mecruiser or rebuild if so. Some 2006-08 Merc 3.0s had the old style carb, rare though.

Update: It was the carb for sure. Had it rebuilt and now idles just fine. Now I have a worse problem. There is a jet of water spraying out of the port side of the out drive. The mobile repair team says there is a gasket that needs to be replaced and they will have to pull the out drive to replace it... Anyone every had this problem before?

If it's spraying water at the lower unit case half, then yes someone did not reinstall the drive correctly. Pretty common if the guy who last removed the drive didn't know sealer goes there.