140 4 Stroke Johnson Stalls

[Nauticstar2]

I have a 2004 140 4 stroke Johnson that is giving me some trouble. I have already taken it back to the dealer but no luck with those folks. When I prime the bulb at the begining of the day it starts with no problems. Then usually sometime during the day it will stall after leaving a cove/spot that I have been trolling around for a while without the big motor on. My guess is that the bulps valve is broken and that gas is going back towards the tank. It will always start with no faults but then up on plane it will just cut off or stall down to an idle. The dealer replaced the anti syphon valve in the gas tank but the bulb also has one. What do you think? Thanks in advance.

 

[tony_cliffy]

Re: 140 4 Stroke Johnson Stalls

Nauticstar,<br /><br />Possibly similar situation with my 2004 Johnson 115Hp 4-stroke, except mine randomly stalls immediately after starting. It will then start up and run fine after the second restart. Sounds like you are just able to get up on plane before yours stalls.

 

[Nauticstar2]

Re: 140 4 Stroke Johnson Stalls

Just not sure. It usually starts with no problem and im just guessing there is enough gas in the line to the bulb to get up on plane and then it hits an air pocket or something. Good luck with your quest too.

 

[JDA]

Re: 140 4 Stroke Johnson Stalls

I was searching the board to see if anyone else was having the same problem. Bingo! Thought I would bring it to the front. My 140-4-stroke is doing exactly as Nauticstar2 described. It doesn't happen when I initially launch the boat but after I've traveled some distance, shut the engine down and fished for a while. When I start back up, take off and get up on plane it will stall.

I checked the anti-siphon valve at the fuel tank which seemed to be working properly. I can blow air (breath) through from the threaded end but not from the nipple end. I have replaced the fuel line, squeeze bulb and connector. There is a fuel-water separator which has a new filter, no apparent leaks anywhere. I too have the system checker gauge, no warnings or flashing lights. It just seems to run out of gas.

 

[ftltony]

Re: 140 4 Stroke Johnson Stalls

Interesting dilema!

At first, if this were a 2 stroke, I was thinking "low oil" or "oil sender" problems since the motor will usually shut down and force you to low speed when the oil was low in that case but, being a 4 stroke.....

Questions....

1. The next time you took off and the motor stalled, was the bulb "full" or was it empty?

- if the bulb is full, your gas isn't flowing back to the tank and all your check valves are working.

2. Do you have a temperature gage and what is it reading?

- this almost sounds like a "vapor lock" type of situation where the engine is too hot, especially after you shut it down after a hard/long run and it "boils" the gas in the carbs and the next time you take off, you get no power until you get gas back into the carbs and you can only do this after the motor sits for awhile and cools down so the gas doesn't boil in the carbs again....

 

[JDA]

Re: 140 4 Stroke Johnson Stalls

1. Prior to changing out the fuel line, bulb and connector last week the bulb would be empty after the engine stalled. I would have to pump it to fill it with gas in order to restart. I thought maybe the gauge was off and literally running out of gas and sucking air with the fuel being thrown to the rear of the tank during plane-out so I removed the fuel tank sender and checked the level with a wooden "dip stick". The tank was at least half full, gauge showing between 1/4 & 1/2 tank.
Last week I changed out all of the above including fuel/water separator filter.
During 2 test runs it would suck the bulb flat and then stall!
Earlier in the week a mechanic said it sounded like the check valve was sticking. I checked it, seemed fine so I tried it again. It would suck the bulb flat and stall. Yesterday before going out I removed the check valve, punched out the seat, ball and spring then reassembled. I squeezed the bulb at the ramp, it was tight. The engine started fine and ran well to my first honey hole which was about 1 mile from the ramp. I fished for about a half hour. It started up, idled fine but right after planing out it stalled. The squeeze bulb wasn't tight but had gas in it. A couple pumps filled it. The symptoms repeated 2 more times yesterday.

2. I do not have a temperature gauge. When the first instance occurred yesterday (1-mile) I doubt the engine was overheating. There's always a healthy stream of water coming from the pee tube. The engine has EFI. I've already tried Sea Foam.

 

[ftltony]

Re: 140 4 Stroke Johnson Stalls

You've got a blockage in your line, NO doubt about it!

Heres and interesting question:

If you disconnect your fuel line BEFORE the bulb, can you blow thru it and make bubbles in the tank? I don't know if you have a backflow device in your tank but if you don't you should be able to blow air into the tank thru the line. And since you knocked your out, you should REALLY be able to blow thru it back to the tank!

On a different note, I have mentioned this one before, I have a buddy who has a Whaler and he had the same problem, no fuel to the motor, flat bulb, motor dead after running, etc.

Assuming you have an "in floor tank", on the side of the boat, there is an "overflow" fitting which is basically, a "vent" for the tank. A Mud Wasp" made a nest in there. The mud plug only allowed so much airt to flow thru the vent. After the boat would shut down, over time the air would travel past the mud plug, he could pump up the motor and run it again but after a few minutes, same problem!

He took a hanger and cleaned out the mud and after that, things were fine and dandy again! Have you by any chance checked that?

I am betting though that you have some type of obstruction .....

 

[JDA]

Re: 140 4 Stroke Johnson Stalls

Yes its an in-floor fuel tank, Key West 186 Bay Reef. I have been plagued with mud wasps, dirt/mud dobbers or whatever you call the little devils!
I disconnected the fuel line at the tank, got my wife to watch the fuel line where I disconnected it on the inlet side of the fuel/water separator and blew compressed air through, no blockage. I then stuck the air nozzle into the elbow fitting that goes into the tank (fuel line outlet) and gave it a couple shots of air @ (20-30 psi) while my wife put her hand over the fuel vent, said she felt air coming from it with no apparent blockage. With both fuel lines disconnected I blew air through the separator, no restriction noticed.

Thanks for all your good suggestions!

 

[ftltony]

Re: 140 4 Stroke Johnson Stalls

MAN That's Screwy!

Now when you say your wife is feeling the air flow thru the vent, how MUCH air is flowing thru the vent..?!?! If you have the same set up I did on my Key West, there should be an inspection plate where the fuel inlet AND the fuel vent go thru the side of the boat and there should be an inspection plate on the floor where the fuel tank is.

Can you disconnect the vent line from the fitting on the boat and blow air into the tank thru the vent line after you remove it from the overflow fitting?

If you have trouble blowing into the vent line, can you take up the inspection plate on the floor and disconnect the "vent" line and remove it from the boat?

Maybe all you need to do is run a "snake" or some piece of wire thru the vent line.....

Additional questions .... I'm sure you've checked this but ...

1. Is your fuel/water seperator a "one way" unit and do you have it hooked up backwards?

2. Is your primer bulb installed with the "flow arrow" pointing towards the motor?

 

[clemsonfor]

Re: 140 4 Stroke Johnson Stalls

Weak fuel pump maybe?

-nate

 

[ftltony]

Re: 140 4 Stroke Johnson Stalls

That would be the OPPOSITE of a "weak" fuel pump if its flattening the bulb! If your pump was weak, it wouldn't suck the gas out of the tank and the fuel pump is mounted on the motor AFTER the bulb.

I'm betting its GOT to be something in your vent line!

 

[JDA]

Re: 140 4 Stroke Johnson Stalls

1. Is your fuel/water separator a "one way" unit and do you have it hooked up back wards?

2. Is your primer bulb installed with the "flow arrow" pointing to wards the motor?

1. Yes, its directional and correct.
2. Yes, correct.

I disconnected the vent hose from the tank, no blockage from nipple at tank. I blew compressed air in the nipple and the tank expanded. After I stopped and removed the blow nozzle, air came back out the vent nipple unobstructed. I removed the cover from the Attwood external p-trap type vent and blew air @ 80 psi through the vent hose at the tank out through the vent. It was wide open, no blockage.

I disconnected the fuel filter under the cowl, no obstruction. I also removed both hoses from the fuel pump. With my breath, I could blow from the inlet side out through the outlet, no problem. However, I could not blow from the discharge side back through the inlet side, tested good.


The only other thing I can imagine is some foreign object in the tank, randomly clogging the suction tube when I throttle up and slosh gas to the rear of the tank. Man, that will be a fun fix!


ftltony, thanks again for your suggestions! I can tell you have "been there, done that".

 

[CharlieB]

Re: 140 4 Stroke Johnson Stalls

When you say that the primer bulb is flat, do you mean that you can SEE that it is physically flat? OR< that it FEELS flat when you first squeeze it then it pumps up?

I' betting on the last.

Install a clear section of hose just after the fuel pump so you can watch for air bubbles.

A very small air leak sucking into the fuel line before the fuel pump will 'run-out -of-gas symptoms at low speeds, especially if the carbs are a little low from hot evaporation from a recent run.
Yet once up to speed still allows enough fuel flow to stay up to speed.

This is a potentially dangerous condition as the problem begins to worsen you will run too lean and toast a set of pistons.

Find the faulty hose fitting and seal it before it gets expensive.

 

[JDA]

Re: 140 4 Stroke Johnson Stalls

It was physically flat, collapsed, sucked flat, nothing to squeeze.

 

[Rudy Brown]

Re: 140 4 Stroke Johnson Stalls

This may or may not help, but years ago I had a simular problem with my FIL's boat. Turned out to be a piece of celafane in the tank that would suck up to the pick-up. Then when pressure was off would move away. Kind of a shame to have a boat with a built in tank and have to run it on a 6 gal portable one.

 

[BillP]

Re: 140 4 Stroke Johnson Stalls

A flat bulb means the pump is strong and no air leaks. Sounds like an obstruction in the delivery to me. Test with a portable tank with a different hose.

 

[JDA]

Re: 140 4 Stroke Johnson Stalls

Thanks for all the helpful tips and suggestions. I've made sure everything is vented and free from obstructions. I've installed a new check valve, will water test in a few days and give a report.
Quite honestly , I first suspicioned the engine/fuel pump considering the original poster I referenced had the exact same symptoms, identical engine. Considering it will suck the bulb flat (at times) definitely not the fuel pump. I could see an electric fuel pump working intermittently but mine is mechanical. Sounds like there's a gremlin in the gas tank!

 

[JDA]

Re: 140 4 Stroke Johnson Stalls

Water tested the other day, engine stalled, had to pump the bulb. I called KW, tech stated that the fuel pick-up tube in the tank had a fine mesh screen over the tip and that over time the screen could become clogged with debris and create problems. I removed the screen from the tube, will see what happens next time out.

 

[JDA]

Re: 140 4 Stroke Johnson Stalls

Well, that wasn't the problem but I feel I found the cause, so far so good.
Considering it never happened in cool weather I too thought it may be some type of vapor lock. The fuel line (with bulb) was very long, almost serpentine possibly causing a p-trap effect? I shortened both ends of the hose allowing just enough slack for the engine to turn stop to stop without pulling or kinking the hose. I have it zip-tied to the cabling so that the bulb ends are in an almost vertical position rather than lying in the bottom of the splash well. I started the engine several times yesterday after sitting for a half hour or so, the bulb was always tight when I checked it before starting the engine and no stalling problems! Thanks again for everyone's suggestions.