B&S Intek V-Twin flooding only one cylinder ( John Deere)

[1Johnny]

Greetings... any help or direction sure would be appreciated..

I am working with a John Deere L-120 Lawn Tractor with the Briggs & Stratton INTEK 2.0 Twin engine
Model-406777
Type-0139 E1
Code- 050606 YC

Here is the situation:
One cylinder is flooding with fuel and the same cylinder each time..I have replaced the carburetor so the needle and seat can be ruled out as a cause...I have replaced the head gasket and adjusted the valves properly and the compression is equal in both cylinders.....A visual inspection provided no answers and the valves and seats looked good..

I have good spark to each cylinder

Where would you turn next? .. Thank you

 

[don45640]

Is the spark arriving in the one cyl. at the right time? Check timing of spark to flooding cylinder. don-ohio ^)

 

[tcartwri]

How do you know it's flooding? Black smoke? Fouled plug?

 

[1Johnny]

Thanks for your reply Don.. We have checked timing and that is right on

 

[1Johnny]

Hi Tim....Black smoke and the cylinder is filled with fuel....same cylinder each time

 

[ptgdigger]

Have you checked the intake runner and exhaust on the non-flooding cylinder , if that cylinder isn't breathing properly the excess would go to the other side. could be either plugged by a nest or something or have a serious vacuum leak on intake.

Ray

 

[don45640]

I'll be interested to know the end of this one.LOL! Gotta be pulling excess fuel into that cyl. it seems,or just enough air to give compression.Of course,cyl. full of fuel will give false compression reading,just as if you'd put oil into it to check blow-by of the rings.
Check your motor oil......it's probably diluted with fuel really bad. don-ohio

 

[tcartwri]

Hi Tim....Black smoke and the cylinder is filled with fuel....same cylinder each time

When my twin B&S did this, it was the intake valve sticking open in the cyl head. This caused severe reversion in the intake manifold and produced huge amounts of black smoke. As the head heats up the valve sticks in it's guide and by the time you take everything apart it has cooled down and released it's grip. Any valve ticking when this happens?

 

[1Johnny]

Thanks Ray...Yes that was all cleaned during the head gasket replacement.

Thanks Don...Compression test was performed just after the head gasket replacement... and no the oil was not diluted..

Thanks Tim.. Good point.. I will probably have to look closer into the intake valve for that flooding cylinder

Thank you guys for your help.

 

[don45640]

If the intake is sticking open,compression will not be good. Make sure to let us know what you find out? don-ohio ^)

 

[1Johnny]

OK, so I went out into the shop and looked over things once again this time being more critical and what I found was that YES my oil is diluted with fuel AND I have a much weaker spark with the cylinder that is flooding.. so now I have turned to the secondary electrical system as the cause of the motors malfunction and cause of the flooding condition....

I have searched the Briggs & Stratton site for the manual for this motor so that I can trouble shoot and it appears there is not one available..

Thank you all once again for your replies

....Johnny

 

[alchemysa]

Had the same problem today in a single cylinder B&S Intek in my ride-on. Engine wouldn't turn over, so I removed the sparkplug, and petrol flooded out. (This was only about 30 minutes after having used the mower.)

I may be wrong but i figure the only way that much petrol can get into the cylinder is if the needle and seat is not closing correctly. The gas tank is partially above the carby, so if the needle doesn't close properly then gravity will simply drain petrol from the tank, into the cylinder via the carby, and ultimately into the sump or out the exhaust valve until theres almost no juice left in the tank.

The needle should close the seat simply by having an efficient float, but this Intek also has a solenoid activated fuel shut-off attached to the fuel bowl. (Perhaps thats an indication that this engine has a design problem when used in conjunction with high fuel tanks.)

Anyway, to get to the point, are you sure your needle and seat, and solenoid fuel shut-off is working correctly? (If you have a solenoid fuel shut-off you should be able to hear it click when the key is turned on.)

 

[RandyT]

Had the same problem today in a single cylinder B&S Intek in my ride-on. Engine wouldn't turn over, so I removed the sparkplug, and petrol flooded out. (This was only about 30 minutes after having used the mower.)

I may be wrong but i figure the only way that much petrol can get into the cylinder is if the needle and seat is not closing correctly. The gas tank is partially above the carby, so if the needle doesn't close properly then gravity will simply drain petrol from the tank, into the cylinder via the carby, and ultimately into the sump or out the exhaust valve until theres almost no juice left in the tank.

The needle should close the seat simply by having an efficient float, but this Intek also has a solenoid activated fuel shut-off attached to the fuel bowl. (Perhaps thats an indication that this engine has a design problem when used in conjunction with high fuel tanks.)

Anyway, to get to the point, are you sure your needle and seat, and solenoid fuel shut-off is working correctly? (If you have a solenoid fuel shut-off you should be able to hear it click when the key is turned on.)

The fuel shutoff solenoid on the carb has one purpose and one purpose only. To help prevent it going bang when you shut if off. Had absolutely no effect on fuel flow with a flooding carb.

 

[1Johnny]

Thanks for your reply alchemysa....yes the needle and seat can be ruled out as the cause because I replaced the carb.....

 

[alchemysa]

The fuel shutoff solenoid on the carb has one purpose and one purpose only. To help prevent it going bang when you shut if off. Had absolutely no effect on fuel flow with a flooding carb.

OK. Looks like you might be an expert on this. So why is the cylinder flooding with petrol? Seems to me it must be a needle/seat/float problem even though 1Johnny believes it can't be.

 

[Heavy Junk]

Hello,and hope I can shed some light on your carburetor problem while you still need it. I have personally experienced the 25 hp B&S carburetor flooding which is so extreme, it would flood one cylinder and dilute the crankcase oil with gasoline. Not to worry, the cure is simple and easy to do. The cause is a small simple "O" ring damaged by what I suspect to be the ethanol now added to all pump gas. This problem has happened to my mower twice. Looking at the parts illustration from Briggs & Stratton web site the "O" ring is item number 1123 and is placed over item 160 retainer, solenoid having the groove for its seating position. This ring seals gas in the float bowl from passing the inner walls of item 135 tube, fuel transfer and 160 solenoid retainer which holds the high speed jet in its side. To sum it up, a carburetor repair kit is needed in order to get the small simple "O" ring, one hour or so of labor and you will be back in action. Thanks, Heavy Junk.

 

[linenlad]

I have same sort of problem, one cylinder fouls up with black soot.

 

[DonaldS]

When my twin B&S did this, it was the intake valve sticking open in the cyl head. This caused severe reversion in the intake manifold and produced huge amounts of black smoke. As the head heats up the valve sticks in it's guide and by the time you take everything apart it has cooled down and released it's grip. Any valve ticking when this happens?

..
I use a little Pennzoil 2 stroke oil in all of my 4 stroke engines. It acts as an upper lube. Never had sticky valves or nasty carbon build up in 30 years! Used it in my in my 99 Frontier V-6 since it was new and it still has the original spark plugs. I use half an ounce per gallon in the mowers and half that much in the cars and trucks.

Good Luck.. Don S..

 

[milozano]

Greetings... any help or direction sure would be appreciated..

I am working with a John Deere L-120 Lawn Tractor with the Briggs & Stratton INTEK 2.0 Twin engine
Model-406777
Type-0139 E1
Code- 050606 YC

Here is the situation:
One cylinder is flooding with fuel and the same cylinder each time..I have replaced the carburetor so the needle and seat can be ruled out as a cause...I have replaced the head gasket and adjusted the valves properly and the compression is equal in both cylinders.....A visual inspection provided no answers and the valves and seats looked good..

I have good spark to each cylinder

Where would you turn next? .. Thank you

 

[milozano]

Greetings... any help or direction sure would be appreciated..

I am working with a John Deere L-120 Lawn Tractor with the Briggs & Stratton INTEK 2.0 Twin engine
Model-406777
Type-0139 E1
Code- 050606 YC

Here is the situation:
One cylinder is flooding with fuel and the same cylinder each time..I have replaced the carburetor so the needle and seat can be ruled out as a cause...I have replaced the head gasket and adjusted the valves properly and the compression is equal in both cylinders.....A visual inspection provided no answers and the valves and seats looked good..

I have good spark to each cylinder

Where would you turn next? .. Thank you

Hello 1Johnny,
Did ever find a solution for your John Deere L-120 as I am having the same exact problem?