Im ready to unbolt it and let it sink...

[Racingfan]

2004L CARB
0T834340

I bought a 2004 Procraft last year with this motor... It had been running great according to the guy...
I got it and couldn't get on plane because It would just bog at full throttle. I took it to the mechanic. He rebuilt all three carbs, fuel pump, all new oil and fuel lines.
Tested it on the dyno and said shes ready to go. It was still very slow out of the hole. And by slow I mean it just simply lacks the power to push the boat out of the hole.
Once it stops bogging and finally decides to run it will get on plane and run like a scaled dog. I can run 60-63mph, drop out the gas and gun it and it has excellent throttle response. But at low end it just won't apply power to get on plane. ITS NOT THE PROP! There is something wrong with the motor. Any ideas?

Its as if it has an electrical issue or timing. I don't know. Im almost 100% convinced its not fuel related. It doesn't help to prime it when it does this. It will actually sometimes kill it. I have to put it in neutral and apply about half throttle to get it to start pretty much everytime, but I've been told thats pretty nromal with a carb motor.
I sure wish it had fuel injection!

[JOE54]

checked tuner may fell off

[leonreno]

How does it idle? I have basically the same motor and I do not have to apply throttle to start mine. First pump bulb until firm, second make sure motor is trimmed level (or slightly in), turn key to on and press key in for at least 10 seconds, then start motor. Having motor level when starting is really important. When restarting warm I will usually do the same as above but only press key in for 5 seconds or less, depending on how long the motor was off. If idle is rough (rougher than normal) I would check reeds. I know you say it’s not the prop, and probably not, but does your prop the vent holes on the side?

[Racingfan]

Prop is a 4 Blade with two vented holes obove each blade. One of the two is completely open the other a small hole.

[leonreno]

First check the tuner as joe stated, it’s the exhaust tube inside the midsection, have to drop lower unit and look up inside mid with flashlight and maybe a long screwdriver to see if tuner moves or is loose. Reeds would be checked bu removing intake but idle is normally bad and may also see fuel spit out one of the carbs while running. If spark related you will be better off buying the service manual from your mercury dealer and going through the test there. Could use a timing light to see if all plugs are firing good when problem is occurring.

[JOE54]

+1

[Racingfan]

Ill take you thru a normal routine for me... I always pump the primer bulb until firm. (New last year from dealer). Back it down and engage the throttle about 1/2 way in neutral. Start it. It almost always fires up immmediately. You back off the trailer and let it idle and warm up for a couple minutes and it still idles well. You pick up your partner from the dock, idle out for a minute and trim down 100% and drop the throttle to wide open to get on plane. It will almost always just run at about 3000 rpm and not get on plane. It just acts as if you just gave it a little throttle and lifts the nose but just continues to run at about 2800-3000 rpm and pushes water. Then sometimes it will come up and get on plane fairly well. It NEVER jumps out of the water, EVER. But will sometimes (about 1 out of 10 times) get on plane in about 5 seconds or so. But almost always it will just run at about 3000 rpm for about 2-3 seconds and then it will come out of it and start to power up. It doesn't load up or even necessarilly bog down... Its literally as if the throttle is only engaged about half when its actually full throttle...
It isn't the throttle cable. It is tight and strokes to wide open. I don't know...

[Racingfan]

And again, After it gets on plane and up to full power it will run like a new one. It will run up to around 60+mph and if you drop out of throttle for a wave or whatever and then mash the throttle again, it will throw you back in the seat and power up like it should... It sure seems to me like the CDI isn't working right to advance when trying to take off or something. I don't know how to check that. Spark plugs are clean slightly dark grey. All of them

[John Jackson]

Could be the reeds. Broken reeds will kill bottom end. Have reeds checked and possibly replaced with fiber reeds.

[JOE54]

have you checked the tuner yet, make a trip to GREENVILLE SC. first call EUROPEAN MARINE for appointment

[revlimiter]

Sounds like you need to open up some more vent holes. What prop and what pitch?

[revlimiter]

have you checked the tuner yet, make a trip to GREENVILLE SC. first call EUROPEAN MARINE for appointment

that would be a road trip!

[EuropeanAM]

And again, After it gets on plane and up to full power it will run like a new one. It will run up to around 60+mph and if you drop out of throttle for a wave or whatever and then mash the throttle again, it will throw you back in the seat and power up like it should... It sure seems to me like the CDI isn't working right to advance when trying to take off or something. I don't know how to check that. Spark plugs are clean slightly dark grey. All of them

Don't forget- Sherm @ Sherm's Marine is not all that far from you, and he's a sharp one on these engines, too.

[blackboat]

one other thing you might consider...A friend bought a 2003 19 Procraft,200EFI,6 inch hydraulic jack plate.The boat had a whale tail type device bolted to the cavitation plate. We immediately removed the whale tail because,well it looked bad. The boat ran great top end but wallowed around on the hole shot and would not plane out worth a darn,just like yours. Soo.replaced stock reeds with TDR's,injectors cleaned and calibrated,everything was cleaned up and set to proper specs,tried a number of different props,same thing.The boat was an embarrassment.Midway thru the season we stuck the whale tail back on. Bimgo! the boat shot up on plane like a rocket and ran the same top end.Just throwing this at ya...

[tcproman]

If it's like my procraft, it's needs to get up to around 4,000 rpm to plane