Water In Fuel System

[Jason2tpa]

1993 Yamaha 2 Stroke 25 HP

Hey gang. Unfortunately I got water in my portable 6 gallon fuel can (I discovered a small hole in the tank and my tank sits back near the transom where water gathers) and thus into my carbs. I knew something was wrong when I took boat out for a ride yesterday and engine was sputtering, bogging down, never getting to even half throttle. I'm 100% positive this is because water got into the fuel system, so no need to suggest it's something else. I just had the carbs cleaned and gaskets/valves/etc replaced last week by a professional.

So today I got a new tank, new fuel (obviously), and also added some Seafoam to the tank. Cleared out the fuel line, fuel filter, and bled both carb bowls. Sprayed WD-40 into carb throat and into jets. And she wouldn't crank...not even close. I'm wondering if water got into the cylinders? Perhaps even the plugs?

Suggestions Please and Thank You!

[DennisG01]

"Crank" means to "turn over", as in the pistons physically move.. Do you mean that, or do you mean it won't "start"? I'll assume you mean "start" or attempt to start/fire. Have you checked the plugs? If not, pull them and check them out - re-gap/clean or replace. Check for spark.

It might be something I'm not aware of, but why spray WD40 into a gasoline carb? This works as a starting fluid for diesels, but I'm not sure what it does for a gasser?

Are you getting gas to the carbs and plugs? Do the plugs smell like gas?

[TownsendsFJR1300]

Besides the above, if you pull the carb drain bolts and pump the primer bulb, are you getting fuel coming out?

And with the drain bolts back in, you getting a solid bulb?

[Jason2tpa]

Hey Dennis thanks for quick reply. You're right, i used the wrong terminology. Yes she "cranks", as in the pistons are turning over. No she doesn't start. Normally she"ll start with 4-5 pulls when cold (manual start).

I didn't have chance to check plugs. As far as checking for a spark...I saw my mechanic do this a while back when I first got engine. He pulled a plug but left the coil on. Then leaned the plug up against the block to ground. He had me pull the flywheel so he could see if the plug fires. My point is it be difficult to check if each plug fires without someone else pulling flywheel while I look for the spark. Any suggestions on how I would do this solo?

WD-40 is truly intended to displace standing water (WD--water displacement). So I sprayed it as I described for that purpose. Bad idea?

Now the other thing I noticed is this...I openned carb bowl screw simultaneously squeezing fuel bulb with the intention of pushing out any remaining water but no fuel came out of bowl. I even opened both bowl screws with no fuel draining out. I double checked...fuel is going through line and filter. After the filter, fuel is then routed through the fuel pump. Could there be an air lock in fuel pump? Coukd be the reason no fuel is draining from carb bowl when I squeeze fuel line bulb??

[Jason2tpa]

Besides the above, if you pull the carb drain bolts and pump the primer bulb, are you getting fuel coming out?

And with the drain bolts back in, you getting a solid bulb?

Townsend---

No, no fuel is draining when I squeeze bulb. And yes, when drain bolts are screwed down tight the fuel line bulb is solid. Your thoughts??

[99yam40]

Hey Dennis thanks for quick reply. You're right, i used the wrong terminology. Yes she "cranks", as in the pistons are turning over. No she doesn't start. Normally she"ll start with 4-5 pulls when cold (manual start).

I didn't have chance to check plugs. As far as checking for a spark...I saw my mechanic do this a while back when I first got engine. He pulled a plug but left the coil on. Then leaned the plug up against the block to ground. He had me pull the flywheel so he could see if the plug fires. My point is it be difficult to check if each plug fires without someone else pulling flywheel while I look for the spark. Any suggestions on how I would do this solo?

WD-40 is truly intended to displace standing water (WD--water displacement). So I sprayed it as I described for that purpose. Bad idea?

Now the other thing I noticed is this...I openned carb bowl screw simultaneously squeezing fuel bulb with the intention of pushing out any remaining water but no fuel came out of bowl. I even opened both bowl screws with no fuel draining out. I double checked...fuel is going through line and filter. After the filter, fuel is then routed through the fuel pump. Could there be an air lock in fuel pump? Coukd be the reason no fuel is draining from carb bowl when I squeeze fuel line bulb??

could be there is junk in carbs plugging drains.
If primer firms up then fuel has to be getting somewhere

[TownsendsFJR1300]

Well, that sounds like your getting closer.

Ethonol literally eats up fuel lines and may be your issue. I had the innerds of a marine line break down(it literally fell out and the engine filter caught it)

I would start by pulling the fuel line where it attaches to the engine. Put the end in a container and prime the bulb. See if fuel actually comes out(and should).

If it doesn't, perhaps a bad bulb, clogged pick up, (not sure about the new vents).

If it does, re-attach and follow the fuel flow.

Check the underhood fuel filter, (that its NOT clogged up)

Follow the fuel flow..

[Jason2tpa]

Fuel line definitely sending fuel past the bulb into the filter. No issue there. My question is when im squeezing bulb WITH the carb drain plug open and no fuel is coming out (bulb is firm)...what does that mean?? How do know if fuel is getting past fuel pump cause thats the only thing between filter and carb.

[Jason2tpa]

could be there is junk in carbs plugging drains.
If primer firms up then fuel has to be getting somewhere

Possible yet highly doubtful because carbs were just disassembled and cleaned. But if primer bulb is firm and fuel doesn't come out of carb drain plug when open could that mean fuel is getting "stuck" somewhere...fuel pump? I dont know.

[DennisG01]

My point is it be difficult to check if each plug fires without someone else pulling flywheel while I look for the spark. Any suggestions on how I would do this solo?

Carefully... Depending on your reach, it might be pretty tough. But if there's enough slack in the plug wires, you might be able to do it.

The things I mentioned (and others) are all things to check for when diagnosing an issue - in general, you need 3 things to make a fire - fuel, air and spark. Take away any one of those and you get no fire. Diagnosing via a forum is always tough because, for one, there's almost always valuable information left out of the 'problem description'. It's alright, though, it's just the name of the ****. EDIT: OK, that "starred-out" word is only supposed be g-a-m-e - I'm not sure why I got censored on that!

You're positive that fuel is making it into the filter, but that no fuel is getting to the carb fuel bowls? I'm not a mechanic, nor do I know the 'ins and outs' of all the different motors out there, but what you're saying narrows it down quite a bit (see... more information! ) So that leaves either a blockage in the fuel line to the pump or the carb, or an issue with the pump. Maybe start with loosening the lines and see if gas comes out - then attack the fuel pump. I would kind of "make it up as I go" in regards to diagnosing the pump, so I can't offer any specific information - but I know that others can.

You're right about the function of WD40. However, given that it's oil, I'm not sure how well it's going to combust under the lower compression of a gas engine. I suppose if you only shot a little in there, it's probably a non-issue.

[TownsendsFJR1300]

Pull the hose off to the pump and prime again. Just to make sure you have fuel to there.

I've never heard of fuel not going past the pump when primed.

**When the pump goes bad, it usually leaks fuel into the crankcase past a worn diaphragm.


Please post back what you find...

UPDATE;

I don't know your model # (please post it if you have it) but the pump is on the lower carb on this engine;

http://www.boats.net/parts/search/Ya...TOR/parts.html

As noted above, its looking like your issue may be something/blockage in the fuel pump or lines to it.

[Jason2tpa]

Hey guys just wanted to update you. After the rain cleared up here in Tampa yesterday I went to work on engine. Pulled the plugs. Here was the issue. Wet and smelled of fuel. Even a brown oil color residue. Instead of clean and re-gapping I just bought new ones. They're only $4/plug. Installed new plugs and she started first pull. Ran on flush about 20min. Dropped in the water and ran her for at least a half hour. No issues.

I want to thank all of you for your support. This forum rocks!! Here is my next question:

I need to dial-in the idle speed and mixture. Just got a rpm gauge that wraps around spark plug. Tried it last night. I can't get the engine to idle at or around 700 rpm (indicated in service manual 650+/- 50). The lowest I can get her to idle before conking out is 1200. I read so many articles about fine tuning the carbs but seems like there is no one way. Can anyone recommend a website/article that provides a sequence in tuning in carbs.

For example....do I dial in mix first then speed, vice versa, ect.

1993 Yamaha 25 HP 2 stroke.

Thanks again guys!

[zenoahphobic]

Jason2tpa, so we now take it fuel is in the carb bowls (because it runs) - what did you do that changed that??
Oily plugs probably suggests that you may have been too liberal with the WD 40 spray. BTW it contains alcohol so if run immediately after you sprayed it, it would contribute to combustion.
Your high idle requirement still suggests fuel issue.
Hence check your fuel flow out of carb drain plugs when pumping primer bulb.
Mixture screw is for idle mixture. i.e. basically you turn down idle to obtain minimum running speed then adjust mixture for maximum idling; do the process again until stable lowest idle is achieved.
Someone will advise, I'm sure, how to specifically to do this with your multi carb motor.

[99yam40]

Yamaha service manual comes in handy if you own a motor of your size and vintage which I do not, but do have one for mine

[Jason2tpa]

Jason2tpa, so we now take it fuel is in the carb bowls (because it runs) - what did you do that changed that??
Oily plugs probably suggests that you may have been too liberal with the WD 40 spray. BTW it contains alcohol so if run immediately after you sprayed it, it would contribute to combustion.
Your high idle requirement still suggests fuel issue.
Hence check your fuel flow out of carb drain plugs when pumping primer bulb.
Mixture screw is for idle mixture. i.e. basically you turn down idle to obtain minimum running speed then adjust mixture for maximum idling; do the process again until stable lowest idle is achieved.
Someone will advise, I'm sure, how to specifically to do this with your multi carb motor.

Replaced the plugs. I suppose the WD40 could have caused the oily plugs but i didnt spray much. I forgot to mention the threads nearest the gap were brown burn. So the combination of oil and burn does that suggest the mix is too rich? How does the high idle suggest fuel issue. Or are you saying mix issue?