8n rookie looking for help

Mackz abbott

New User
Well here goes nothing!
-The Back Story

I received my new to me 8n from a neighbors barn, he says this tractor belonged to my great grandfather and plowed all of my family s Feilds for years. My father stated he dreams of "playing around on the tractor in his retirement". My father is no mechanic by any stretch of the imagination. The running joke is "he will build you a house by hand, but he won t install the door handles" being that it is to "mechanical" for him. I found out first hand how true that is, we built my home together a year ago and I installed all the door handles. Anyway- now that retirement is coming in the spring for him, I m attempting to get this tractor up and running for him as a surprise. He knows nothing about me picking it up or working on it. I m really hoping to fix it up and get it into running condition/ convert it to 12 volt/ repaint it for him to "play around on" in his retirement.


-The issues

So this tractor was plucked from a barn where the neighbor was in fact using the tractor for daily fire wood, brush hogging, snow plowing and general fun 2 years ago. 4 years ago, it was rebuilt top to bottom, the entire motor was gone through, parts replaced and seals redone along with a fresh coat of dripping paint! The tractor was used for 2 years after with what I m told was "no issues". After resting in a barn for 2 years with monthly start ups this is what I found. On the initial startup the tractor would run for 5 min or so and sound as if it was running out of fuel when finally shutting itself down. The tractor refused to stay running during any "load", that being anything from a slight incline to letting the clutch out relatively fast. I was told it was the carb and sense I have never even touched an 8n until now, I just assumed my neighbor who ran this tractor for the last 20+ years knew what he was talking about and I purchased the carb and adjusted to specs with no lengthier run times. All parts replaced are brand new and from my research online they are "quality" and not cheap overseas replicas. This is what I have done/replaced so far with no change in the very short run times and sputtering out to a stall with any movement.
Oil change
Oil filter
Fresh fuel changed out 3-4 times now, roughly 8 gallons each time
Points (x2)-set to spec
Condenser (x2)
Cap
Plugs(437&al216) gapped to a .020
Wires (2 different styles)
Fuel line
Sediment bowl
3 carbs (2 zenith and 1 m&s)
10+ fuel screen filters
Fuel tank has been cleaned thoroughly and coated-no rust/debris
Compression test reads 100psi (dry) on all 4 cylinders
All valves are working properly upon pulling the inspection plate
Fuel pours from the fuel line! No shortage! Will run entire tank dry with speed!
New 6 volt battery
Spark appears to be a bright blue indicating to me it is strong


What I have noticed- being a complete novice to these tracors that appears suspecting is
1)The governor upon inspection does have a few extremely small flat spots on the main large "weights"? Or ball bearings.
2) The electrical system appears to be a complete mess- some new- some old, all was tested and appears to be in operational condition, inspected and repaired where needed
3) The throttle control lever has significant play, I can move the throttle from its lowest idling position to half throttle without the tractor even attempting to adjust its RPM s
4) every so often I have heard the tractor while idling create an ever so quiet "pop pop pop" from the exhaust, it sounds like a misfire but it will come and go with no pattern that I can find


Any and all help/advice is appreciated, for the record I am no mechanic, the term shade tree mechanic comes to mind when my skill level is being determined so do please keep that in mind!.

A month ago I couldn t tell you a darn thing about these tractors, today, I am learning about these tractors just as I will be tomorrow. I couldn t think of a better way to spend some garage time/ quality time with my 5 year old daughter then working on her grandfathers retirement toy.
 
I'd say you're doing pretty well for a rookie.

And buying a lot of "spare parts". :)

6v or 12v?

Front or side distributor?

"Plugs(437&al216) gapped to a .020"

Wrong gap. Set it to .025

As soon as the tractor stops running, not 5 minutes later, check for spark and fuel. (see tip # 13)

You need to answer 2 questions before you do anything else:

With the bolt in the carb bowl removed and the gas on, will the fuel flow fill a pint jar in less than 2 minutes?

Next, get out your adjustable gap spark checker * , open the gap to 1/4", hook it up, turn the key on and crank the engine. Does the spark jump 1/4"? Post back with the answers.

And do not buy another new part for the tractor until you can answer this question: how do I know the part on the tractor is defective?

Once you narrow the problem to spark or fuel, post back and tell us what you found (and how you found it) and you will get plenty of help to get your tractor running.



* Don't own an adjustable gap spark checker? Buy one! Not a test light! Until then, take an old plug, open the gap 1/4" ground it to the head & look for spark. It?s not the color of the spark that counts; it?s the distance it jumps.


https://www.amazon.com/AMPRO-T71240-Energy-Ignition-Tester/dp/B00A8FO87S/ref=sr_1_fkmr1_4?ie=UTF8&qid=1513273147&sr=8-4-fkmr1&keywords=ampro+spark+checker
75 Tips
 

You don't say how you checked the fuel flow. See the pic below? This is the fitting that is screwed into the carb. It has a filter on it. Make sure that filter is clean. Then check for fuel flow as Bruce described above.

cO0u1fm.jpg
 
Yes, what Bruce and Cary said goes. You said it is 12V -how did it run before you switched it and, who switched it out and more importantly was the wiring/changeover done correctly? Replacing parts is not the answer. A systematic, root cause problem solving method is essential to any problem. Until you know a part is defective or worthy of rebuilding (first choice), don't waste time and money on new ones that you may or may not need. All FORD major components were meant to be rebuilt over and over and since they've lasted 80 years, is always the best first choice for these machines. Most aftermarket stuff is made in Cheena and not controlled with any quality so you get a lot of junk parts. Three things are needed to run the engine: SPARK; FUEL; and COMPRESSION. The usual culprit is one or both of the first two so concentrate on those. SPARK: Electrical system is vital to giving life to the engine. Start with known/tested battery. It must sustain a charge under load, defined by specific gravity. Starter shops and auto parts stores will bench test it for you. Follow Bruce's 75 Tips to perform spark test. Know also that 99.98% of all non-starting/non-running tractor issues are due to incorrect wiring whether OEM 6V/POS GRN or a 12V/NEG GRN switch over job. Shadetree mechanics and those that just plain don't know muck up the wiring with their rendition of what they perceive a 12V set up should be. One must also know if they have a front mount distributor or a side mount. FUEL TEST -engine off determine if gas flows out of carb. There are a few reasons why it won't and each process needs to be looked at starting with the fuel tank. Bruce's 75 Tips will also give the details. A good carb cleaning and rebuild can never hurt especially if the last one done is not know. If you replaced the carb with 3 different units and 10 fuel filters (OEM?)and they all did the same thing, what does that tell you? It tells me it ain't the carb BUT most likely upstream to the fuel system. The Fuel Sediment Bulb Assembly has a knurled handle control/shut off valve. Turn it off when tractor isn't running. You are doing too many things all at once and not getting anywhere but frustrated. Do one system at a time. Finally, invest in the essential manuals to learn and know about your machine and how to fix/maintain it correctly. Most importantly is to know what not to do and practice SAFETY FIRST. You don't want to get hurt or do damage to the machine that could cost you a fortune to repair.


KNOW YOUR MACHINE:
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THE FORD 8N TRACTOR ESSENTIAL OWNER/OPERATOR/PARTS/SERVICE MANUALS:
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Tim *PloughNman* Daley(MI)
 

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