poor running pre 2200v wt 1998

[bk530]

seems to be mis-firing and running poorly at idle to low speeds a little better at higher speeds but still sound different. I have only had the boat this year and still getting use to it. Just wondering if anybody has anything that I should to/check?

[TeamAllen]

Do you do your own maintenance or do you have a shop do it? Did it run well last year? What has been done to it since last year?

[bk530]

I just purchased the boat in may, I have had a couple odd issues. It over heated due to the impeller blowing up on the owner before me and never removing the pieces. I had the boat running ok after that but it seems sluggish. I have been working on it myself and just wondering if there are anything's that I can check to make sure everything is ok. I did treat the gas after I filled it, I keep it docked at a lake and we have been having a lot of rain.

[NICKYPOO]

I'm sure Boatwakes will end up seeing this.

Meanwhile, have you replaced the fuel filter, plugs, dist cap, wires?

Honestly, it sounds like its starving for fuel. Boatwakes always seem to have different and better advice than me.

[Ruger761]

Which motor does it have carb, EFI, multi port injection? Sounds like fuel, but almost sounds like fouled plug or bad plug wire.

You said working on it yourself what all have you done so far?

[boatwakes]

Lets repower it with a diesel... Thanks Nick, I just throw a dart at the board most of the time but what Ruger asked, what motor do you have and what specific symptoms are you noticing vs what you are feeling?

[Ruger761]

Diesel sounds good to me

[bk530]

I have a 350 mag engine, it was a consignment boat from a local boathouse. They had sold the boat new in 98 and I am the 5th owner, they changed all the fluids and said that it ran fine. I am just wondering if I can do anything easy to see what the issue might be. I did not know if it could be the gas, it is at half a tank and I have been using STA-BIL in the gas. I will see if I can get plugs, and a fuel filter and check the wires.

[bk530]

it does seem to run better at high RPMs, the idle is a little ruff.

[Ruger761]

Without knowing more it can be all the above. Lets start with fuel filter and some plugs. Full the tank with fresh non ethanol gas if you can find it. Now that its summer I personally switch to Sea Foam vs Stabil on the gas.

[boatwakes]

There's a stupid little ignition sensor inside the distributor under the rotor that has been the cause of many a woe for mercruiser owners. It was finally updated to the new potted design in 2005-6ish, so it should be updated if it hasn't been done already. Here's how to tell without having to open the cap: there are two wires that exit the back of the distributor that are white/green and white/red. IF there is a third wire and it's black, the unit has already been changed out but if your distributor just has the first two, replace it. SENSOR ASSEMBLY (#87-892150Q02) and double check firing order (1-8-4-3-6-5-7-2 clockwise looking down on the distributor). Could you also please post the serial number, that way I have all the info I need for what type of induction it is.

[Ruger761]

I had better check that sensor on mine just to prevent any future issues as well.

[bk530]

boatwakes: thanks for all the help..... engine sn#0608529. I am not able to check the distributor until this weekend as I have it docked at the family lake house. I will be installing a new filter and plugs this weekend to see if this will help with the issue, I also keep over heating and I will be replacing the thermostat as I think this might be the overheating issue the boat does not have a sea strainer but I will be installing one of those as well. Any other preventive maintenance suggestions are welcome as I would love to have an event free rest of the summer.

[NICKYPOO]

I bet the boat has blown an impellar in the past and was never cleaned out properly. I would check down the line to try and find any rubber chunks in the cooling system.

[bk530]

I have already found a bunch of them, the guy before me did not take care of this boat at all.... Which I am finding out the hard way.