Engine stalling problem
 

Hi Folks,

Have a engine stalling problem which just can't seem to be resolved?

Problem is engine runs fine 'in the yard' with 'muffs' attached. I've run for more than 30 min. even up to 2500RPM without issues.

However,when I run boat in the water, it coughs, sputtters and stalls just about immediately, attempting to go more than wake-speed. Doesn't seem to run under a 'load', but appears to run fine idleing in the yard
'on the motor-muffs'.

I am using ethanol gas, which still has Sta-Bil and ValviTech treatment from
last season. I checked samples of gas, and all looks ok, doesn't look like any water in gas. Gas looks clear, no bubbles, or any type of foreign particles. The fuel/water separating filter has been changed-out twice. I changed spark plugs. Dealer has performed a coplete Carb rebuild. No difference in engine behavior? Dealer still thinks there's some water in the system. They have ruled out this being 'fuel pump related.

OK, if there still s some water in the gas it doesn't seem prevalent or obvious? I have 35 gal of gas in the tank now. If I have to drain it out and start with fresh, any siuggestions how I would go about doing this?
I'd have to have 7-8 five-gal cans, which is inpractical. Secondly, what am I suppose to do with this gas once drained? Dealer has not been very much help, and is not setup to handle this situation.

Would appreciate any suggestions about the gas question, or maybe comments about the engine behavior not being gas related.

At 'wits end' !!

My snowmobile and PWC, which tend to sit for long periods of time in the off-season, run like crap at the beginning of the year. The gas with Sta-bil, ethanol and the other stuff just does not want to run well. I found that the ethanol + stabilizer combo just does not burn well at all. The ethanol has been murder on engines from what I have seen, especially the older gas.

If it were me, I would find a way to safely siphon out as much of that old gas as I could. Put in a nice batch of fresh gas...just gas, no additives (unless you need to mix in oil). Fire it up and rev it up a bit. After it runs for a little while, change your spark plugs as they may have fouled.

As for disposal of the old gas, I can't help you there. I have heard of people using that old gas in lawn mowers, and even in their cars. Not sure I would recommend that...

The best way to rule out the gas as an issue is to rig up an auxilliary tank of gas and run it on that temporarily to see if the problem persists. Something like this: http://willardssmallengines.com/shop...-gas-tank.html would work. If you have a generator, roto-tiller, or some other small 4-stroke, engine powered device, with an easy to remove fuel tank, borrow it for the test.

Cheap fix....a one dollar bottle of Wal-Mart carb/injector cleaner. Expensive fix....a six dollar bottle of Chevron Techron carb/injector cleaner. And keep your fingers crossed?

One reason an engine will run poorly under load, but ok under no load is because it is not getting the extra fuel it needs. You said they checked the fuel pump but what about the fuel filter or some other restriction?

The timing also becomes more critical under load. If you don't have electronic ignition the timing could be off or not advancing as you accelerate.

Dave R's idea of using a seperate tank is a good one.

Sounds to me like the octane rating in your gas has gone south. If your gas is really bad it should have a distinctive odor.

You're going to have to eliminate one thing at a time and Dave's suggestion is the best way to start. I am assuming it runs fine in neutral in the water and just starts acting up when under load. I once had a similar problem that turned out to be ignition related. If the fresh gas doesn't solve it look there. Good luck.

Kind of the same
 

I had a trouble like yours and as FLL suggested in previous message try running fuel system cleaner through. I the dealer look at it and I alos cleaned the carbs and jets. That cured the trouble for a short time only to have it return. I added a bottle of fuel system cleaner and ran the motor and it slowly came back to life..

Also try the spare gas tank trick to rule out bad fuel.

GOOD LUCK!

Engine stalling problem
 

You didn't mention the age of your motor, but I would check coils and wires for cracks. Running the engine in your driveway with muffs, is a lot drier environment, than when the boat is in the water. Putting a load on the engine under damp conditions might be just enough to cause a short to ground. I've had a similar problems in the past.

Check this out: http://www.bostonherald.com/business...ome&position=2

The problem could be different tjings depending upon engine? carb or inj.? age? if inj.could be as simple as a cable binding,carb a float stuck. Doesn't sound like fouled plugs because as you bring up the idle should hear and feel a missfire.Need more info on engine

I vote with Bear....change the filter.

maybe
 

SAMIAM...maybe the good folks over at Whining Butcher could take a look at it???

Is the fuel line pinched?

(Occam's Razor). :D

I feel your frustration. I had the exact same problem with an older mercury outboard. I spent a lot of money on diagnostics, electronic ignition components, water impeller, primer bulb and flexible fuel line. Ultimately the problem was a seven dollar piece of copper tubing that came out of the fuel tank, and ran through the side of the transom where it was attached to the flex line and bulb. There was a ninety degree elbow where the line came through the hull and it had cracked there. It was a simple as that. I hope you find the cheap fix first!!

Engine stalling problem
 

Thanks for all the suggestions, much appreciated !

FYI as follows:
1995 4.3LX Mercruiser 220HP
Not electronic ignition

Again... engine runs fine 'out of water' even revving....

Marine mechanic performed following checks:
- Carb kit just installed (new jets, needles, springs, accel pump, etc)
- Carb float is metal not plaastic type.
This was not replaced with as part of rebuild kit. Tech said it was OK.
- Distributor cap and rotor OK
- Fuel pump, they said was OK, but not sure if tet performed?
- New plugs installed (by myself)
- Fuel/water filter replaced twice
- Coil cable looks good, but did no check perfomed on coil

Using an Aux. gas tank to test is a great idea, but doesn't look like it would be a simple adaptation hookup, between tank and gas line feed?

Going to siphon out as much gas as I can, and replace with fresh gas.
Adding some more Gas line water remover treatment, and maybe some octane booster. Can't hurt at this point !

If this fails, going to contact another marine dealer to see if they can perform gas removal and discard old gas ? TBD?

My guess is that all systems are OK, and the 'ethanol' gas is the culprit !

Thanks again!
Bigdog

A FANTASTIC product to try....
 

Bigdog:

Go to any NAPA and ask for "Seafoam." This stuff is beyond belief. Developed over 50 years ago for tha marine industry, it's now available at the retail level. To quote the manager of NAPA: "I could get rid of every other product in here and just keep Seafoam...I always keep half dozen bottles at home." It's even better than the Lucas products...hope it's helpful

You'd want it just upstream of the fuel pump. This will eliminate the entire fuel tank/lines and the fuel filter, and feed known-good fuel directly to the carburetor.

Fuel hose replacement is conspicuously absent form your list of things done. It's cheap and easy.

not a mechanic but...
 

When running your engine out of water, are you running water through the engine to cool it?
Is is running long enough that you see it spitting out of your exhaust?

Maybe someone more mechanically inclined could comment on this thought...

If you had a crack in your exhaust manifold jacket, you would not necessarily see it and it might cause problems where water could get into the engine. If you are running your engine out of water, not hooked up to water or it is not being run long enough for the water to run through the system or to build up adequate pressure to cause a problem it would always run good out of water, (if that was the problem)

I had a crack in my exhaust manifold on the exterior and it would leak water when under way, I replaced it at not much cost or trouble myself, I was told a crack on the inside of the jacket would have been worse.

Or it could be some other cooling system related issue where there is a leak, where water is going somewhere it should not.

read your post too quickly...
 

not sure my idea still applies unless out of water at 2500 rpms is very different than in the water at 2500 rpms...:confused:

When exactly did this problem start??

Essentially your motor starts breaking down under load. This would tell me that there is an ignition or fuel delivery problem somewhere.

I seriously doubt a 95 V6 has points & condenser, so to clarify... you do have an electronic ignition.

The fuel side is an easy test.... attach a pressure gauge in-line before the carb.... splash boat, check fuel pressure!

The ignition side is a bit trickier. But I have my suspicions!

Step 1: You said YOU changed the spark plugs. I would check them to make sure you didnt crack one installing them. Pull each one out one at a time and thoroughly inspect the plug. Note the color of the electrode on each plug. Any plug that looks signifigantly different from the rest might indicate a problem with that cylinder....


Step 2: When was the last time your ignition wires were replaced? I think these are the most likely culprit! The insulation on those breaks down over time, especially in a moist marine environment. You might have inadvertantly cracked a wire when you installed the spark plugs.... Replace each wire individually so as not to screw up the firing order. Double check that you didnt screw up the firing order when you changed the plugs the first time.


Hope this helps...

Woodsy

Engine stalling problem
 

OK, here's the latest update.

Marine dealer can pump out old gas, but has no means to dispose of fuel.
Consequently, I would have to supply enough containers to hold 35 gal of fuel. Went to local automotive repair shop with same question, got same answer.

As I may not be able to remove old gas, I may just have to keep running until the level gets down to where I can add new fresh gas.

In the meantime I'm going to remove water seaparating filter and keep dumping fuel after running for 15 min each time. Again, after already doing this several times there is no apparent inidcation of water in the fuel.
Also have added gas additive to remove any water (HEAT), and also added an octane booster. I suspect gas looses it's properties when sitting over long periods of time.

To answer a previous comment, I am running plenty of water through the engine, and can see it coming out the ports of outdrive where it should be.
Engine temp.reamins to stay low.

Going to purchase a new fuel line hose, to connect from tank to fuel pump,
BTW is electric. Should be a inexpensive replacement.

To answer another question about the plug/coil ignition wires, not sure if these have ever been changed. Boat is 13 yrs old and engine only has 160hrs believe it or not.... Wires look like new, but I guess youcan't tell the inside condition of wires from outside appearances. Will see if NAPA dealer
has a replacement. Can't hurt to replace... Right?

Also, I believe engine only has a rotor, no condensor or points.

Suggestion to perform a fuel pump check presure check, I would have to bring back to marine mechanic. Surprised they didn't do this as SOP. Sound like it was too much trouble for them ?

One last question which nobody suggested.... Could I have a bad Coil, and would that exhibit this type of engine behavior?

Thanks again.
Bigdog

BigDog...


DEFINITELY replace the cap, rotor, wires & check the plugs you put in. 13 year old wires (regardless of usage) are pretty much junk! If you inspect the Cap, rotor & wires closely you will prob see signs of carbon scoring... Make sure you do this one at a time and double check the firing order BEFORE and AFTER you finish.... I cant stress that enough!

Its possible you have a bad coil.... similar symptoms. but change the wires first. I think the wires are arcing out...

I wouldnt worry too much about the gas.... when you change your fuel water separator, dump the gas into a clear glass container and cover. Let it sit for a few days... if there is water in the gas you will see it.

Just keep adding new gas to the current gas. Go to Y-Landing and spend the $$$ on the Hi-test... Hi-test mixed with Junk usually yields a decent enough mixture.

Woodsy

A set of wires 12 years old worked, but a year later, won't? I don't think it's the wires, because the engine would misfire at an idle, which isn't your problem. But here's a test anyway.

The easiest way to check plug wires is to run the engine in complete darkness and watch.

Throw an opaque tarp over the engine area at night to get rid of any extra light, and allow lots of time for your eyes to adjust to the darkness. This test is not effective if there's ANY light around. Tonight there will be no moonlight.

Failing wires will provide a real light show, sending sparks out to anything nearby, even the other plug wires! Watch the area at the coil for sparks there. You can vary the speed, but any sparks indicative of wire failure will be apparent even at an idle. Note the location of nearby turning or hot accessories which could present a hazard in darkness.

Ignition manufacturers once marketed a transparent distributor cap. It might have been boring to watch the sparks after a time, but it was an interesting idea.

2BlackDogs...

You might have a point if the wires were undisturbed.... However he changed the spark plugs. In order to change the plugs the wires need to be removed and flexed around.... this will cause cracks to form in the 13yr old silicone allowing the wires to ground out. Its also quite possible the firing order was screwed up as well when he put it back together.

The firing order is 1-6-5-4-3-2

As far as the wires causing a misfire at idle or unloaded... the misfire is probably still there, however the motor isnt under load, so it is alot less noticable. If you really want to get into specifics you can take an ohm meter to each wire and measure the resistance... You are looking for approximately 600 ohms/ft resistance. Less resistance is better! If the wire is bad you will usually see a reading ALOT higher.

No need for the tarp/dark weather voodoo testing method!

There isnt really any great test for the coil... when idling (unloaded) on the hose its going to take along time for a coil to get hot & malfunction vs. an almost immeadiate malfunction under load. If the motor runs great for 20 -30 minutes or so on the hose, then misfires & dies.... its quite possibly the coil


Woodsy

Two Black Dogs, great idea to check the ignition wires, will do tonight!

However.....
Woodsy you may have unravelled this mystery when you stated
'If the motor runs great for 20 -30 minutes or so on the hose, then misfires & dies.... its quite possibly the coil'

I have been running the engine on the hose for 20-30 and seems to run fine, real smooth, even rev-it to 2200RPM without issues...... Then about the 25-30 minute mark, it starts to mis-fire & dies !!!! Exactly as Woodsy stated !

Could it be the coil heating up, then mal-functioning ? One could only hope !
Could be just the coil wire, and not the coil, or maybe both?

As a few have stated, there's no real way to tell if the coil is bad?
How much do these little buggers cost ?

Still going to try wire night-test to check wires.

All comments appreciated !

Thanks,
Bigdog

The plugs were changed in response to poor performance, or, to put it another way, the problem appeared *before* the plugs were changed.

Except in air-cooled applications, silicone wires have exceptional longevity. The wires may be 13 years old, but the engine has 160 hours on it. I put that many hours on the lake in one summer.

And actually, there is a way to check a coil. Snap-On and MAC sell relatively inexpensive coil testers, and there are probably far cheaper testers on the market today. You just dial in the suspect coil to the point of spark failure, and the analog dial will advise if the coil is marginal or not. I'm not advising that bigdog go buy one, however. Use of darkness to pinpoint an ignition problem IS worthwhile and costs nothing. Humidity, like we had yesterday, increases the effects.

As for the old gas, it can be put in proper containers and sold to those who would mix it with fresh gas. The cost of new containers can be recouped when the old gas is sold. With those additives, I doubt that the gas is so bad that it can't be used as normal. Even then, it can be added in increments to a near-full tank on a truck, lawn mower or the older 2-stroke outboards, which have a great tolerance for old gas mixes.

2BlackDogs...

There is a big difference between "poor performance" and outright not running! BigDog did not state that he changed the plugs as a result of this problem occurring. I was under the assumption that he changed the plugs due to routine maintenance and the not running problem appeared right after.

Woodsy

You can check the coil with an ohm meter and a toaster oven. Measure the resistance from - terminal to the high voltage output cold, then heat the coil up to 200 degrees and measure again. Should be little difference. That said, a new one is like 28 bucks from Napa (Sierra part number L47-5433 is liekly what you need).

Did you ever figure this out? Just currious what it was!! I hope so!!

Jon

gas problems
 

I use gas with ethanol in it and last year I put that Stabil stuff in the tank. I had probems with it this year. I have an 115 Evinerude and use two six gallon tanks. I took one tank of fresh gas/oil mix and it worked great, so after it got running I switched back to the old gas. I finally burnt the old gas up, but it would not start good on that tank. Till I put fresh gas in it. Waste not want not With a built in tank you would have to find a way to do this.

Did you ever find the problem. I have a 92 four winns, OMC, 5.0, Carb. My boat will run perfectly for hours, then just stall out at cruising speed. 1st time, we were running for about 2 hours, and boat seemed to run out of gas, restarted it, and it would only idle. Then died completely. I played around with the upper fuel filter and she re-started and ran perfectly for another hour.

I got home, changed seperator, cleaned upper filter (it is only a screen) and added some stabilizer to the gas.

Took the boat our Sunday. (we run on the Hudson River down here in New Jersey). We did a 60 Mile Run up the river. About 55 miles into the ride, less than 5 miles from the marina (right in front of the Indian Point Nuclear Reactor for anybody that knows the area) running along at about 25 knots and same thing. Just died, like it was runnning out of gas. This is after almost 3 hours of running. Started it up, and it would only run up to about 1400 - 1500 RPM, but then after about 5 - 7 minutes, Died Out again. I took a wrench and tapped the fuel line by the upper filter (screen) and she started up and ran like a champ. However at that point, the water was getting rough and I did not want to chance another stall.

So, any thoughts ? Could it be dirt in the tank that gets sucked up after a few hours of running? Could the float in the carb be hanging up, then when I fool around it drops back. Why would it run flawlessly for hours and hours, then die?

I am at a loss. Anybody want to buy the boat, it is getting that frustrating.

Condensation?
 

Did you check the carb for condensation? I ran into that issue a couple years back on my old boat. The condensation would build up and it would run fine for a while but then stall out.

No, but I will try anything. We put the boat away for the winter, and before so I had my mechanic look it over. He could not come up with anything. Only thing he suggested was the coil, perhaps after a very long run, the coil begins to fail ? But I think it is more fuel related. Oh well, the wrap is on and we will start over again in the spring.

Thanks for the reply

Hate to beat a dead horse but I think checking the simple things will always be more eficient and cost affective that tossing darts at the problem.I would purchase a spark test lead ( most prts stores for less than $ 10.00 ) put it on a plug then plug the wire for that cylinder and run the engine till it stalls. You will then be able to safely crank the engine and verify wether or not you have spark and go from there.

engine stall
 

u may want to check your fuel lines the gas with ethanol will eat the rubber lines from the in side. on boats older than 2000. also fuel pump diaphragm gets weak and this will cause the boat to stall as fuel line closes up because it gets weak

Engine stalling problem 'AGAIN'
 

Hi....

My engine stalling problem, has reared it's ugly head again today !
Thought I had this problem cured, guess not.

At the beginning of the season, at the advise of 'JST_4_KIKS', I completely drained my gas tank, all 35 gallons. (BTW, I used all this gas in 3 different cars, without any issues).

I then filled tank with 89 Octane, and added a can of 'Seafoam'. Because of the lousy weather this summer I've only been able to get boat on water a couple of times. On each occasion, we only ran the boat out for about 30 minutes, during which we usually take a swim, have lunch, then return to
to the boat ramp. Only ran the boat around half-speed, but seemed to run smooth w/o stalling, coughing, or backfiring.

Well, today I took boat out for a short run. We ran boat for only about
15 min did our routine (lunch and swim), then pulled anchor to take a short ride. After a couple minutes the boat started to cough sputter, and backfire, and I started to loose power. Turned boat around and headed back to boat ramp. Got back to ramp ok, but stalled twice in lesss than 1/4 mile.
Pulled boat out and parked boat back in yard.

I immediately got on the phone to the marine techs, the same which just replaced all my bellows and trim senders. Just picked up the boat Saturday !

Anyway, they had performed a complete Carb rebuild last season, because I had this same stalling problem back then. They said to me at the time that this was the problem, and probably caused by the ethanol gas, and have seen this issue many times with other customers. BTW, they didn't at the time test for any other causes, they just did the Card rebuild. Trusting their experience and knowledge I let them go ahead with the job, $300 !

After this was done, I only had one opportunity to use the boat before the end of last season. Again we probably only used for 30 minutes, 15 mi to get to our destination and 15 back ! It seemed to run OK, at least it didn't stall.

Today the marine techs, said it sounded to be spark related issue, and may be Distributor Cap, Rotor and/or Timing? Sounds like at this point they may just be guessing?

Again, I can run the engine in my yard on the motor-muffs forever, without the engine stalling, or backfiring. And rev-it without hesitation.

Very Frustrated and just want to get to the bottom of the problem, so I can spend some quality time boating with what's left of the summer.

Your comments and suggestions are appreciated.

Thanks,
Bigdog

From your symptoms I'd say it's a fuel issue. Check your fuel pump.

After this happens again, check for fuel pressure (find the schrader valve and depress it. Does fuel spurt out?

I'm thinking something might also be wrong with your float valve. Give the top of the carb a good whack the next time you stall out.

Winnipesaukee is right about the float value, I had that problem with our I/O and it got it running again, although if you had the carb rebuilt last year I wouldn't think it should be a problem this soon...but give it a shot.

The other thing it could be is the water separator needs to be changed out. When they become full of water or sludge the engine tends to bog down and die. Cleaning out a fuel tank is not an easy thing to do and you could have easily missed some sludge or water.

The other thing to do with ethanol in the fuel is to keep your tank full. If you run for a half hour or so you've probably burned several gallons of fuel and that will leave room for condensation to form. I have read it only takes a couple of weeks for the phase separation to begin and once that happens there is water/sludge in the tank again. (If you put it away last fall and it wasn't completely topped off then it attracted moisture over the winter)

I have never tried Seafoam, Startron got my engine at least running again and this year I am running StaBil formulated for ethanol on the recommendation of the marina. It claims to prevent corrosion of aluminum fuel tanks as well as everthing else ethanol related.

Replace the fuel filter as well.

As far as being able to run it in your yard okay that wouldn't be unusual since the fuel problem will show up when you try operate it under load. It uses more fuel then and sucks in the bad stuff in greater quantities.

If all you paid for the carb rebuild was $300 you got off cheap! I had to have the 4 carbs on my 115 Merc Outboard rebuilt and it was just under $740!

Good luck

It sounds to me to be an ignition related issue. Carb would be a constant happening where as ignition can come on with added heat from running and will tend to be intermittant. I would start by taking a spray bottle while running the engine on muffs and misting the cap and then the wires looking for the engine to stumble. If nothing changes then remove the cap and check for corosion on the contacts and rotor as well as the pick up. Hope that gives you a little help,keep us informed.

Engine Stalling Problem continued
 

Here's the latest update....

Spoke with marine mechanic about my engine stalling, backfiring problem
and he thought 'ignition problem'. This is the same marine tech who performed Carb rebuild last July to supposedly correct this issue.
The Carb rebuild was definitely needed, however never really corrected the initial problem.

I personally don't think it's a engine fuel problem, because of the 'back-firing'.
I don't think fuel starvation would cause this type of behavior? A bad fuel pump, would stop fuel delivery, but I don't believe would cause 'back-firing'
Maybe someone can comment on this !

Mechanic said bring boat back to him and he'll work with me to correct.
Now thinking he'll replace Distributor Cap and Rotor. He has had several boats come into shop recently with same symptoms, and after checking
Distributor cap and Rotor, found corrosion in all cases.

I have never replaced same myself, and the second owner. Have had boat
3 seasons, but only put maybe 100 hrs on boat. Not sure when previous owner replaced these parts before or ever ? Could potentially be the culprit for this issue, but bad Coil could also be the problem. Right now it's
basically the process of elimination, starting with the least expensive items first, and working up from there !

'2BlackDogs' suggested checking the ignition wires in darkness and that if the ignit. wires, Coil, etc were arcing this would definitely be obvious, and provide a light-show ! Well, tonight in complete darkness, I mean I couldn't see my hand in front of my face, I started up the engine, and could not see any spark arcing coming from ignition wires, Distributor, or Coil.
Nada, zip, nothing ! If anything was spark/arcing it was not visible.

Will keep Forum informaed about progress. IT WILL BE FIXED !
But my wallet may be empty........:(

Bigdog