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Fuel problem

2440 Views 17 Replies 7 Participants Last post by  blackj
For about the last month I have been fighting a fuel problem on my 8N. The tractor will start and run, but occasionally it will die, no special time or reason. I tracked the problem down to fuel not coming into the carburetor in a constant flow. I finally got to the point that I replaced the sediment bowl assembly, fuel line and the elbow to the carburetor. I also just got the fuel tank back about a month ago from a repair shop that cleaned the tank and coated the inside. Could my problem be that the vent hole in the tank is plugged up with the coating? Other then that I could not think of any reason why the flow of gas is so inconsistent. I am open to any suggestions, most of you have more experience then I do.
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For about the last month I have been fighting a fuel problem on my 8N. The tractor will start and run, but occasionally it will die, no special time or reason. I tracked the problem down to fuel not coming into the carburetor in a constant flow. I finally got to the point that I replaced the sediment bowl assembly, fuel line and the elbow to the carburetor. I also just got the fuel tank back about a month ago from a repair shop that cleaned the tank and coated the inside. Could my problem be that the vent hole in the tank is plugged up with the coating? Other then that I could not think of any reason why the flow of gas is so inconsistent. I am open to any suggestions, most of you have more experience then I do.
When and if it happens again, remove the gas cap to see if the vent hole could be clogged..If it quit, get a vented gas cap.

How did you determine its not getting enough fuel ??
When and if it happens again, remove the gas cap to see if the vent hole could be clogged..If it quit, get a vented gas cap.

How did you determine its not getting enough fuel ??

I first undid the drain bolt to the carburetor. At first it drained pretty constant and then it quit, then it would start to drain again. I then undid the gas line from the elbow going into the carburetor. It would shoot a stream of gas out then it would almost stop and then it would shoot out gas again. Do you think I made the right diagnosis? I am new to this so I may not be troubleshooting the problem right.
when she starts to die again, add some choke.. that should keep her going, then reach up and loosen the gas cap.. might ge a 'whoosh' sound.. if that then lets you drop the choke and get her running you found the problem.

soundguy
I first undid the drain bolt to the carburetor. At first it drained pretty constant and then it quit, then it would start to drain again. I then undid the gas line from the elbow going into the carburetor. It would shoot a stream of gas out then it would almost stop and then it would shoot out gas again. Do you think I made the right diagnosis? I am new to this so I may not be troubleshooting the problem right.
That "pulsing" stream sounds like a clogged vent, to me. When the fuel stops flowing... air is headed back up the fuel line to equalize the pressure... then fuel starts to flow again.

Like Soundguy and Ken said... try removing the cap to confirm... then replace it with a vented cap.
I first undid the drain bolt to the carburetor. At first it drained pretty constant and then it quit, then it would start to drain again. I then undid the gas line from the elbow going into the carburetor. It would shoot a stream of gas out then it would almost stop and then it would shoot out gas again. Do you think I made the right diagnosis? I am new to this so I may not be troubleshooting the problem right.
Did you remove the elbow ?? There is a filter in there..
Did you remove the elbow ?? There is a filter in there..


Yep, I put new elbow and filter on. I have a new filter in the sediment bowl and in the gas tank as well. Hopefully when I get home I will try the gas cap to see if that will make a difference.
I did a quick internet search but where do most people get 8N vented gas caps. Is there something special about an 8N gas cap?
I did a quick internet search but where do most people get 8N vented gas caps. Is there something special about an 8N gas cap?
Take the old one to any auto store and match it..
Go to NAPA for a good one, last one I got from the auto parts place would not vent all the time and would starve the engine one day and not the next.
For about the last month I have been fighting a fuel problem on my 8N. The tractor will start and run, but occasionally it will die, no special time or reason. I tracked the problem down to fuel not coming into the carburetor in a constant flow. I finally got to the point that I replaced the sediment bowl assembly, fuel line and the elbow to the carburetor. I also just got the fuel tank back about a month ago from a repair shop that cleaned the tank and coated the inside. Could my problem be that the vent hole in the tank is plugged up with the coating? Other then that I could not think of any reason why the flow of gas is so inconsistent. I am open to any suggestions, most of you have more experience then I do.
How many times do you turn the knob out at the bowl? Turn the knob out two times to run normal. Turn the knob out all the way to run on reserve. If I turn mine out all the way it will run for about an hour and shut down. I seen the same thing on a 8N that a friend sold. He turned it all the way out and it died after it had run for a while, I turned the knob all the way in and backed it out two times and it started and ran fine same thing mine did. I have not seen a cutaway of the fuel tank so I can't explain why it happens. I just know it happens. It runs out of gas when I turn knob to reserve when it has gas in the tank.
knap-sack - I normally turn the sediment bowl valve two or three turns.

I was not able to get home early enough to work on it tonight. Hopefully tomorrow my wife will let me work on it.
Rusty tank??

Maybe thats plugging the line.
Hopefully tomorrow my wife will let me work on it.
Tell her you got permission...

I told my wife that if she works in the kitchen, I will work in the barn..

(Doc says the scare will not show...:trink40:)
Ingersoll444 - I just had the tank cleaned and coated a little over a month ago. I think that it is the coating that is clogging the vent hole in the tank. This whole fuel thing started when the lines got clogged with rust. I worked on the fuel lines and filters while someone else cleaned and coated my tank.

Ken - I have already been overruled on my desire to work on the tractor today. My wife already called to tell me what we would be doing after work. With Halloween coming up I do not see any quiet time with me and the tractor any time soon.
I wanted to thank everyone who replied to my problem. I did get a chance yesterday to work on it. I am almost sure it was a venting problem. Fuel runs constant now. I let it run and drove it for about 45 minutes without a hiccup. Now I can move on to another problem. I noticed my exhaust is about ready to rust off. When I first got the tractor a few months ago the exhaust pipe looked pretty rusty but seemed solid, but not now. It looks like it should be an somewhat easy fix.

Thanks again everybody.:thanku:
I wanted to thank everyone who replied to my problem. I did get a chance yesterday to work on it. I am almost sure it was a venting problem. Fuel runs constant now. I let it run and drove it for about 45 minutes without a hiccup. Now I can move on to another problem. I noticed my exhaust is about ready to rust off. When I first got the tractor a few months ago the exhaust pipe looked pretty rusty but seemed solid, but not now. It looks like it should be an somewhat easy fix.

Thanks again everybody.:thanku:
Exhaust pipe or manifold ??
Good point, Both the manifold and exhaust pipe are pretty rusted and I am not sure what exactly is rusted through enough to cause the exhaust pipe to be loose. The exhaust pipe seems to be loose at the clamp that attaches it to the manifold. I hope it is the pipe that is the problem because that seem relatively easy to fix. If it is the manifold, I might be asking you all a lot of questions because I have never replaced something like that before.
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