lots of fuel in #3 cylinder of 3.0lx 1993 model

[randy becraft]

Hi again Had a no start problem with this 93, 3.0LX, and felt at first it was water in tank...Then noticed the plugs looked soaked and pulled them all out to clean and check gap..Figured i'd turn engine over a few times to clear cylinder's of excess fuel (thinking maybe I had just flooded it); and found lots of fuel spraying out of #3 cylinder..Hoping you guy's will tell me it's something cheap like maybe the fuel pump. Found the fuel filter at carb turned around backwords( with closed end facing outword). Could this have anything to do with the excess fuel in cylinder? Thanks again

 

[Don S]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Are you sure it was all fuel and not a fuel and water mix?

Empty that cylinder by cranking with ALL the spark plugs out. Then do a compression test on the problem cylinder. Also, dry the spark plug, hook the plug wire to it and ground the plug to a clean ground and see if it actually fires and spark jumps the gap of the plug.
How old are the spark plugs and what kind?

 

[randy becraft]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Don, I cranked engine over three times at ten second spins and still had lots of fuel blowing out of #3 cylinder. Was afraid a spark would set it off so I stopped until the morning when I can wash bildge out some and try again .Plugs are NKG'S #BR67S, and pontoon had sat for over three years with a bad upper unit when I bought it. Had it running and had a lot of black smoke when first started after sitting so long.Replaced upper unit, bellow's and shift cable.Then while adjusting shift cable I noticed valve cover was leaking real bad..So I replaced it (had to remove fuel line for that and noticed fuel filter in carb housing was in backwards),then the starter went south....lol Fixing that and trying to start engine, I thought I had flooded it because I had spark on all plugs and a lot of fuel on them.Also noticed that fuel was dripping into intake several minutes after trying to start.No wetness on outside of carb like a stuck float but it's dripping...All plugs are cleaned and re-gaped from 0.45 to .035.... All wire's fired their plug. Will locate my compression test kit in morning. What should I be looking for besides the cylinder holding pressure? What should a good reading be for these older engines? Also with it not starting, engine can't be warmed up..Thanks again !

 

[Don S]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

With all the plugs out, there should be no suction from the cylinders with the plugs out to suck fuel into the cylinders. I would bet that after setting for 3 years the needle valve in the carb is stuck open you your fuel pump is dumping raw gas into the manifold. Possibly just the way the engine is tilted the fuel is going into #3.

Disconnect the fuel line from the carb, put a hose on the end of the line and put the hose into a container to catch the fuel.
Disconnect the purple purple wire from the coils plus terminal (if it's the EST, remove both wire connectors from the coil) and you won't have anymore spark from the ignition. Then crank it and see if the fuel clears out. It will take some time to clear, but you should see it lessen in short order.

 

[randy becraft]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Thanks again Don...You'r a big help to me and lots of others out here. Will keep you posted on results tomorrow.Good evening.

 

[randy becraft]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Morning Don, Well got fuel pumped out of cylinder and ran a compression test with all plugs out. .All pumped up to 150 psi, then slowly lost down to around 100; then just lost all pressure to 0 psi. Woundered if my gauge was losing air some where, but its a new $90.00 craftsman set..So guess it should work ok...Replaced all plugs and tested #4 and it leaked down really fast compared to the other three that took maybe one minute to go to o psi...It don't look good does it..Guess more was wrong than a bad upper unit as last owner stated..

 

[Don S]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Cylinders don't hold pressure, only your gauge does. So that is a non test.
What you need to do is a leakdown test to find out how much leakage you have, but that has nothing to do with your problem. If you got 150 compression on all cylinders, that's fine.
Now find out how so much fuel is getting out of the carb.

 

[randy becraft]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Guess having each cylinder on TDC when testing would have helped..Did get excess fuel out of cylinder and engine started and ran once warmed up, but would back fire through carb ir reved too fast. Ran engine for ten minutes and shut off.Then re-started and ran for another minute or so. Gas was still dripping into intake when engine was shut off , and tapping on carb bowl didn't seem to free up needle ,so I took carb off. Took out jets and any other moving part inside and cleaned them along with all passage ways with carb cleaner and replaced. didn't have a ruler to check float so I guessed at adjusting it to stop fuel alittle earlier. Went too much and wasn't getting enough fuel to start engine. Squirted just a small amount...Took carb back off and am trying to figure without a special ruler ,what is egual to 1-3/32. That is the float drop measurement. Thinking it might be same as 1 3/4"..Float level measurement is 3/8"...May buy a carb kit to get the ruler ect..I'm not a carb guy, so if I don't get it right, i'll look for another good carb to fit engine..Got dark on me again Don..lol Thanks again

 

[randy becraft]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Oh , Forgot to mention that while engine was running it was at 1000 rpm's. Tried to lower idle and it didn't want to idle at less than 800 rpm's. 650-700 is called for..Even at 800 it seemed alittle rough...Good news is that the shift cables seemed to change really well.Thanks for that info too..

 

[Don S]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Sounds like it's time for a carb rebuild. Be sure to inspect the float, replace if you are unsure.

 

[randy becraft]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

Hi Don, Well I rebuilt carb(twice lol) and still dripping fuel Took air horn off and fill float bowl almost to top and venturi started dripping fuel.Once fuel level droped maybe 5mm's from dripping, it would stop.Venturi gasket and the screw with gasket looked fine.Could that check ball under the venturi with spring be causing my problem? Seem to gravity feed from bowl side through venture passages. Thinking that maybe it's not seating. Have re-checked my float adjustment's several time's, and replaced fuel pump. Oil level was up and it was due to excess fuel, so I first thought fuel pump went bad. Still flooding, so it's back to carb...Waitting on tax return to afford another carb if I can't get this one right.Thereisn't a screen and check ball in the accellarator pump well as some have mentioned.Not even a grove to insert hold down clip above a screen, so I'm thinking it wasn't made for one there..Just the check ball under the venturi..Have changed oil as it was two inches above full because of the fuel. Thanks again

 

[Don S]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

The float bowl is never full, maybe 1/2. That is what the needle valve and float level controls.

J..Have changed oil as it was two inches above full because of the fuel.

You need a fuel pump, not a carb

 

[randy becraft]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

The float bowl is never full, maybe 1/2. That is what the needle valve and float level controls.



You need a fuel pump, not a carb

Just put a new pump on...$178.00 ..I didn't think bowl would be that full when adjusted correctly. Someome told me to try filling it like this to see if fuel would start dripping.Seems that it has to be from carb as new fuel pump didn't help matter's.Kept goinging back in carb so much to re-check float level(14mm's) and drop(27mm's) that I messed up base gasket and had to buy second carb kit to get new gasket.One other thing,the new float doesn't have the dot at toe for measuring setting's. It's got a straight raised ridge across center that I assumed I had to use as a measuring point.Is that correct? Oh, fuel was noted in oil earlier last week and pump was changed as was oil.Just saying dripping continuals along with flooding while trying to start.Clearing cylinder's buy removing plug's and fuel line to catch can worked as you instructed.Engine fired up and seemed to run pretty good..Started to fine tune air mix when oil and gas mix started blowing out of pcv fitting on top of valve cover. Shut engine off for a few minutes to study ,then tried to re-start...Fired up good again but oil/gas mix was bubbling out of dipstick tube..Shut off again to check oil and it was 2" over full and full of gas.Thats when I figured the pump had let go and dumped fuel into crank case.But dripping and flooding has started back even with new pump.Really thought I had carb fixed with kit as it ran so good until the spraying thing last week.Sorry so long a post..It's the weekend and I have nothing better to do.Thanks again for all you'r insight.

 

[NHGuy]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

The float you bought should have install & adjust instructions in it's package.
I'd check your fuel pressure, it should be nice and low, probably around 7 psi. Someone will come on and know exactly.
I'd also check that the needle is sealing in the seat by putting 10 or 12 lbs vacuum to the fuel inlet while your carburetor is flipped over upside down.
If those tests don't help the fuel dumping you are going to want a new carburetor or a pro rebuild. Or you can really tear the carb all the way down yourself and make sure every orifice is clear, no vauum or air leaks, and everything works as designed. If I was unsure of myself I would find an older carb guy to do the carb over, experience really can be a great resource. Carburetors have a lot of little things about them that must be done right. Don't buy a rebuilt unless you get it near where you live and can get some help if it does not work perfectly from the get go. In my opinion a proper rebuild by a skilled carb builder is better than a new one from a mass production outfit.

Maybe that backwards fuel filter was someone's half azzed repair for you fuel flow problem.

 

[randy becraft]

Re: lots of fuel in #3 cylinder of 3.0lx 1993 model

How about my half azzed ability to follow instruction's..Just downloaded float level adjustment's using a float like this new one and the level adjustment point was different from the drop, so I bent it to where it looked to need to be in picture and it worked!Engine fired right up and I was able to adjust engine air mix to where it ran pretty smooth.Couldn't get it to idle as low as manual says ,but it close. Pops some when throttled up really fast, but I hope to get it better on the water.Let it sit for half hour and it fired up with a touch of the key. Feel both great and kinda stupid as I know it was my lack of knowlage that caused you guy's so much grief.But if not for you all, I'd been lost. We here all appreciate all you'r time and insight. Thanks again