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Discussion Starter #1
I have a pieced together 8n with a rebuilt 2n motor I recently picked up, has been converted to 12v. ran great for a while then started having issues. The po had rewired it horribly and left out the resistor so it burned the points. I have redone all wiring, new resistor, changed to electronic ignition, new 12v coil, new plugs, wires, rotor, cap, etc. Replace the old cut up fuel line with aftermarket filter for an original. has new fuel tank, and sediment bowl, cleaned the filter in the 90 on the carb. Cleaned carb out and put new float, float needle, needle seat, and gaskets.

problem I have now is that it seems to be starving for fuel when you put a load on it. Sometimes that is a box blade that gets overloaded or sometimes it is as little as letting the clutch out. It just loses all power and spits and sputters, usually dieing. Giving more throttle makes it worse. Give it a few minutes and it will start right back up and idle great but as soon as you put a load on the motor it sputters and dies again. Will throttle up when no load is on it.

any ideas or suggestions?
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You've done a nice job. It looks great! The things that first come to my mind are the carb. needing to be adjusted, needing to be cleaned (something partially clogging it up), or the governor needing to be adjusted (if it has one).
 

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Discussion Starter #3
adjustments are possible, it is possible I missed some crud in the carb but I really put the effort in to make sure I got it all. Gov has not been touched but it was working flawless before I had issue with the points, all gov linkage moves freely and when it starts to stumble it seems the gov is trying to give more throttle. It seems to me that it is acting like the carb bowl is running out of fuel faster under load than what the fuel line can flow. I disconnected the fuel line from the carb 90 and it flows a nice steady stream. there was trash in the 90 filter but it has been cleaned. Not sure where to look next.
 

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I've got a 9n that does the same thing. I haven't got around to messing with it, as it's been sitting for over a year while I've been busy with other stuff. Hopefully I get around to it sooner or later.
Anyays, when I engage the brush hog or get into the thick stuff, I have to pull out the choke briefly until it stabilizes. I also think it's getting starved for fuel.
 

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I thought that this might be of some help:



FUEL FLOW ISSUES:

The Ford 8N Tractor fuel system has three (3) screens. All three of those screens need to be clean for proper fuel flow. A good way to test the system is to put a can under the carb, remove the large plug at the bottom of the carb, and then open the fuel valve on the tank. You should get a good steady stream of fuel after the carb drains. If the flow of fuel slows down significantly after what is in the carb is gone, start looking for the problem.

As mentioned above, one screen is in the tank. You have to completely drain the fuel and remove the fuel shutoff valve assembly to clean that one. Don't forget to also drain the reserve fuel supply by screwing the fuel shutoff knob all the way out. If you don't, or that screen is badly clogged, you will still have about a gallon of fuel in the tank when you remove the fuel valve assembly. Ask me how I figured that out. Before starting this repair it might be a good idea to have a replacement fuel valve assembly. The old one can probably be cleaned, but a replacement will have your tractor ready to go again much faster. You can always rebuild the old one, and keep it as a spare.

A second screen is located just above the glass sediment bowl at the bottom of the fuel shutoff valve. Loosten the bottom nut, remove the glass jar, and the screen is above the seal. Before removing the glass bowl, it is a good idea to have a replacement gasket and filter to put in there. It might not be a bad idea to have a replacement glass bowl in case the old one gets dropped on your concrete floor.

The third screen is attached to the fuel inlet elbow on the carb. Remove the fuel line and unscrew the brass elbow to get to that one. It is made right on the end of the brass fuel line elbow adapter.

If any of the screens is clogged, look immediately upstream to find the source of the problem. Usually the problem will be a dirty or badly corroded tank. Flushing and cleaning the tank may help, but if the problem is corrosion, you need to fix it or get a new tank. There are several tank repair products available that coat and seal the inside of the tank and may fix the problem. Make sure the coating is suitable for ethanol fuel if you run pump gas with ethanol.
 

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Discussion Starter #6 (Edited)
The fuel tank is brand new and shiny clean inside, the sediment bowl is brand new, the fuel line is brand new, and the 90 in the carb was removed and cleaned thoroughly. New float, needle, and needle seat in the carb. Fuel has been drained and replaced with fresh non ethanol just in case (I only run non eth in it). From stone cold the tractor will start perfectly, I can increase throttle with good response, and will run great for anywhere from 2 to 5 minutes, when this problem started I would get 20-30 minutes of use before sputtering started. After that it will start to act like it is starving for fuel when under load, spitting and surging, rpm dropping and then coming back to life just before it stalls, after another minute or so just the load of letting out the clutch in 1st gear causes sputtering and engine dies. Once this happens it is slightly harder to start but will start, sometimes once restarted you can't even move it because any load will cause it to die other times it will run and drive but is weak and sputters and surges. Let it sit for a bit and it gets better. Longer it sits, the better it runs for a longer duration. Entirely new electrical system except the 12v 1 wire alternator (coil, wiring, plugs, cap, rotor, everything), swapped over to PerTronix electronic ignition. I know coil issues can cause some of the same symptoms but it has been replaced with a new 12v one. Is there a testing procedure/resistance value for them?

p.s. I've tried loosening the fuel cap in case of vacuum, no change.
 

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Could be the float level setting also, if all else is clean up to that point. To check proper level in the bowl, first you need to find a, normally 1/8" pipe thread barbed fitting, and about 12"-18" of clear plastic tubing. With fuel off, remove the bottom drain plug, then replace it with the barbed fitting. Slip the tubing on the barbed fitting, then turn upwards 180º in a gentle curve, so as not to pinch the tubing off. Turn the fuel on, and you should see fuel come into the tubing. Holding it along side the carb. bowl, will show you the fuel level inside the carb. bowl. It should be approx. 1/4" from the top of the fuel bowl.
 

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Sounds like you are doing a lot of guessing here. The next time it dies IMMEDIATELY get off the tractor and check for a good hot spark, then pull the plug at the bottom of the carb and check fuel flow. Will it fill a pint jar in less than 2 minutes. Until you find out if its a spark or fuel problem you will just be chasing your tail.
 

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When it starts to fail loosen the gas cap to be sure it is venting enough and second get rid of aftermarket in line fuel filter you installed. Make sure the 3 screens are in place and clean, they are all you need.
 

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Discussion Starter #12
Waiting on new plug wires at the moment, One got caught and pulled into the belt while l was trying to test spark when hot. I appreciate the help and ideas but If people would look at the work that has been done in the posts above it would cut down on my post wasting your time. I have not been guessing and throwing parts at it, some of these were replaced by the previous owner and some were replaced by me for good reason, such as the electronic ignition added due to the PO leaving out the resistor and the points toasting. The pictures are when I brought it home, that's why I made sure to list above things like me already replacing the fuel line back to original to get rid of the aftermarket fuel filter. Not trying to be ungrateful for the help and suggestions, I'm just trying to keep from wasting your time and cluttering the thread as at least one other member has expressed having the same problem and a tidy thread will be easier to follow along with.
 

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I had the same problem. The carb kit was a joke to me. I went to Ebay and bought a rebuilt carb...put it on...ended my problem
 

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Did you put the old coil back on and try it? (Yes you may have bought a brand new bad one)
Did you put a hose on to see where the fuel level is in the bowl?
Did you test for a hot spark the last time it died?
Several things can cause your problems. Need to nail down if it is spark or fuel.

Educated guess is that you need to clean the carb, but at this point its hard to say if its a fuel problem.
 

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Discussion Starter #16
Well, put new plugs wires on it, throws a good hot spark, do not have the old coil anymore. I had tossed it because of weak spark. Splurged and got a $50 Amazon carb and it seems like it fixed the problem, runs better than it ever has for me. I won't know for sure until I run it a few more times and work it hard but hopefully this solves the problem. I appreciate everyone's help and feedback.

Sent from my SM-N950U using Tapatalk
 
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