Boat top speed 10 mph!

[goboardgo]

I have a 2000 21v that I have owned since new. It has 850 hours on it and has not given me any mechanical problems until now.

It seems like it is starved for fuel. The fuel filter has been changed and there is plenty of fuel pressure. We have put Sea Foam injecter cleaner in the tank and have run the boat approximately 4 hours so far with the injector cleaner. There is a noticeable vibration. It starts up fine when I first put it in the water, but after it is warmed up it is extremely hard to start. Kinda of like a flooded car, but I think that is lack of fuel.

We have our "Wake the World" event coming up in a few weeks and I will need to pull those kids from the Children's Homes.

Any ideas?

[MoneyPity]

In neutral can you get motors rpms to 1800-200 range?

When running in gear what is the max rpm you can get?

If you get boat up on a lift or trailer is there a lot of black film on the fiberglass.?

[chpthril]

I have a 2000 21v that I have owned since new. It has 850 hours on it and has not given me any mechanical problems until now.

It seems like it is starved for fuel. The fuel filter has been changed and there is plenty of fuel pressure. We have put Sea Foam injecter cleaner in the tank and have run the boat approximately 4 hours so far with the injector cleaner. There is a noticeable vibration. It starts up fine when I first put it in the water, but after it is warmed up it is extremely hard to start. Kinda of like a flooded car, but I think that is lack of fuel.

We have our "Wake the World" event coming up in a few weeks and I will need to pull those kids from the Children's Homes.

Any ideas?

Did it come out of winterization this way, or has it been running good till now. Was it put up for winter with a stabilizer of some kind in the tank and allowed to run through the fuel system and injectors before being stored for the winter? So its run apx 4 hrs in this condition? I'd look for something left unplugged like a knock sensor or coolant sensor (CTS). Make sure none of the spark plug wires have not fallen off. Did you actually check the fuel pressure with a gauge, or just seems like it has some fuel pressure? If so what was the actual PSI?

[goboardgo]

It will rev fine in neutral. Max rpm in gear is about 2000 rpm. There is no black film or smoke from the boat.

The boat started this last fall. My mechanic checked it over the winter and changed the filter, checked the pressure and replaced some part that I can't remember the name of. We put injector cleaner in the tank. He said try it sometime over the winter and let's see if this solves the problem before getting into something more expensive. Well winter turned into spring and here I am.

I just want to try everything I can before spending alot of money that I don't need to spend. My disposeable income has been disposed!

[dogbert]

I have a 2000 21v that I have owned since new. It has 850 hours on it and has not given me any mechanical problems until now.

It seems like it is starved for fuel. The fuel filter has been changed and there is plenty of fuel pressure. We have put Sea Foam injecter cleaner in the tank and have run the boat approximately 4 hours so far with the injector cleaner. There is a noticeable vibration. It starts up fine when I first put it in the water, but after it is warmed up it is extremely hard to start. Kinda of like a flooded car, but I think that is lack of fuel.

We have our "Wake the World" event coming up in a few weeks and I will need to pull those kids from the Children's Homes.

Any ideas?

Have you ever changed out the fuel pressure regulator? Mine went a year or so ago. It's a real pain to get to on our boats. If it feels like it's starved for fuel, that could be it. Mine alarmed when this happened at higher RPMs. The tech had to read the code to figure out what it was. At first I thought I was overheating.

[goboardgo]

No codes showed up on the diagnostic test. Could it be bad and not show a code?

[dogbert]

Not sure...the best way to tell is to check the fuel pressure when it starts acting up.

[goboardgo]

I guess I will try having a gauge attached while we are driving.

[goboardgo]

Dogbert- What kind of tower do have & do you like it?

[R&T Babich]

... It seems like it is starved for fuel. The fuel filter has been changed and there is plenty of fuel pressure. ...I think that is lack of fuel....

Have you checked the fuel pressure under load?
At idle the pressure is easy to maintain when there are obstructions in the line.

Have you checked the anti-siphon valve?
The fuel tank pickup will probably have a 1/4" NPT to 3/8" hose adapter fitting.
In it is a small check valve to prevent fuel leaks into the bilge from a small leak.
If it is clogged some fuel can get thru, but not enough to maintain fuel pressure above idle in gear.
Here is what it looks like: http://www.marineengine.com/products...php?in=2560414

[Timmy!]

What kind of injection do these have? Throttle body or sequential or multi-port or ? Just wondering if it's throttle body and one of the injectors is bad.

I assume that they do not have EGR? If they do, it could be that the EGR is plugged up too (common problem on 4.3L V6 motors, but possible on V8's as well?)

[dogbert]

Dogbert- What kind of tower do have & do you like it?

I have a Monster Tower and it's been great. For the money, it's a great value. The newer tower they have is 8" taller, too. I like the accessories they offer and I can collapse it when needed.

[dogbert]

What kind of injection do these have? Throttle body or sequential or multi-port or ? Just wondering if it's throttle body and one of the injectors is bad.

I assume that they do not have EGR? If they do, it could be that the EGR is plugged up too (common problem on 4.3L V6 motors, but possible on V8's as well?)

It's an MPI. One other thought I had was that if you've never changed out the plug wires, they could have gone bad. That would explain lack of ignition at higher RPMs because they'll heat up. My mechanic told me that they really need to be replaced with the spark plugs after 400 hours, mainly because you run a marine engine at higher RPMs than a car. He also told me that after 400 hrs, they start to degrade, so maybe one of yours has gone bad and is making a marginal connection....something to check any way.

[da.bell]

^^ wouldn't that make the exhause fumes smell a little "richer" than normal? More of a gas smell...

[Joeprunc]

Usually when I see an engine problem I look at Spark, Fuel, and Air. Pull the air filter off and see if that helps at all.

But honestly this issue reminds me of the time I left the choke on, on my dirt bike. It idled normal, but ran like crap when I gave it any gas, changed my plug but it still continued...a few seconds later saw the choke still one. But my thoughts are your engine is EFI, so all that would be electronically controlled.

When my fuel pressure regulator went out in my Chebie it only had problems starting and idling after the start. Once the truck started and idled for a few seconds the pressure from the fuel pump kept enough pressure to the injectors....but if I remember right it was only a $20 part.