Water in carburetor?

[93LundProV]

I have 40 hp 1993 mercury, and today while on the water my motor died on me and i heard some knocking along with it. I opened my motor case to find my carage full of water and some water coming out by my top spark plug. I seen that my carb was probably sucking some water when it filled up. Now offcourse my motor will not start but still turns over. now what?

 

[ONERCBOATER]

Re: Water in carburetor?

i'm confused???? where would the carb get water to suck up? I am thinking you blew a head gasket if you got water coming out of top plug.... the knocking part is scary though....

 

[Texasmark]

Re: Water in carburetor?

The water coming out by your spark plug is from your water jacket gasket leaking. Those engines didn't have head gaskets, or separate heads.

On water in the carb, I'd guess that the engine sucked up some of the water that came from the water jacket gasket...just an odd occurrence and no engines of this type don't like to mix water and fuel/air. Otherwise the two events are totally unrelated.

Mark

 

[93LundProV]

Re: Water in carburetor?

Im sure your correct mark. Assuming you are, what are the steps i should take in order to get back on the water?

 

[Texasmark]

Re: Water in carburetor?

If the 4 cylinder, the water jacket cover has a gasket that can be replaced...there is no head gasket as the heads are an integral part of the block.

Main thing is to clean up any corrosion that is at the interface of the block and the cover. There are 2 schools of thought when installing gaskets. One is a dry installation and the other is to include some sort of cement to assist the gasket is sealing. Both sides with rant about how their way is the only way. You'll have to make up your own mind.

I like to use cement as corrosion that has always been there for me, makes little pits in the mating surfaces and the cement fills these little pits and improves the seal. Since the water pressure is only a few psi, I use a thin film of blue RTV on both sides of the gasket.

The screws are usually corroded up and you have to be very careful in taking them out so that you don't twist the head off. I like to use a quality penetrating oil and an impact wrench on a low hammer setting to do the job, or make an impact wrench out of an open end wrench and a hammer. Don't get overzealous with the hammer. Clean up the threads prior to reinstalling and don't over tighten or you may strip out the threads in the block. When the screw seats the cover and the RTV squishes out, immediately following that the torque resistance on the screw will sharply increase. A couple of taps with the hammer after that is all I give it. I don't have the actual torque spec and most folks don't have a torque wrench so........

I never had to go into a 3 cyl so I got out my service manual for my 90 3 cyl and it looks like Merc. stayed with their original design in that the head is an integral part of the block so oyou only have the water jacket cover and it's gasket...no separate head and no head gasket to complicate the process.

On the rest of it, I'd run the engine on muffs with the cowl off now to ensure that you don't have water sitting somewhere and it's corroding up your internal engine parts. If you have access to the gasket and get with the replacement now, then I wouldn't bother with the run out.

HTH,

Mark

 

[93LundProV]

Re: Water in carburetor?

I replaced the water jacket seal today then proceeded to trying to start it up and get it running, and getting rid of any water but failed. First i just turned it over without plugs, then i noticed some gas/water coming out of a valve with like a spring on it by the carb, which would sometimes not leak and sometimes come out decent at times. I cleaned the plugs, heated the plugs, gave it a couple shots of starter and nothing i only got one pop. My next guess was picking up some new plugs tommorrow. My afternoon ended when my starter would not stop, now when i connect my power cables it startes turning over on its own, and the starter felt hot and my power cables were getting hot. So all in all things are not looking good.

 

[93LundProV]

Re: Water in carburetor?

I found this thread http://forums.iboats.com/showthread.php?t=257582 which explains alot of the same problems that i am having but there is no answer to his problem. Other than it sounds like i need a new solanoid.

 

[Chinewalker]

Re: Water in carburetor?

If you have water in the carbs, they need to be drained! Remove the main jet plug at the bottom of the carb(s) and prime the bulb until nothing but clean fuel comes out...

 

[CharlieB]

Re: Water in carburetor?

Check your fuel supply, you may have gotten water from the gas pump!

 

[Texasmark]

Re: Water in carburetor?

Check your fuel supply, you may have gotten water from the gas pump!

Not a bad idea, but isn't the mesh in the fuel filter deliberately so small the water molecules can't get through?

Just curious as I felt comfortable they it was and even though I am picky about where I buy fuel, I never worried about it.

Mark

 

[CharlieB]

Re: Water in carburetor?

Particle size is the big difference between a water seperating filter and standard in-line filters that only keep the grit particles out of the carbs.

Ya gots ta get pretty small to keep the water out. In-line screens won't do it at all.

 

[93LundProV]

Re: Water in carburetor?

Replaced the solenoid today, drained the carbs and pumped a bunch of fuel through the lines, and replaced the plugs and repeated many of the steps from before and still nothing. I figure check compression and maybe my gas supply tommorrow. Im not sure what else i can check, its as if the kill switch is on, the only action i can get is with starter fluid and it just pops like a backfire.

 

[CharlieB]

Re: Water in carburetor?

First, never use ether, there is no oil in it for the bearings or rings.

Have you had the flywheel off to check for a sheared key, putting the timing off and causing a backfire?

 

[93LundProV]

Re: Water in carburetor?

CharlieB you hit it, a sheared key was the problem. Thanks to everyone here that helped, very much appreciated. What a great site!