I'm jumping in here late with a thought. I had a similar experience with a portable generator. The issue I found was a faulty oil pressure sensor. It ran perfectly after replacing. Jim G.
9n sat for a couple of weeks and now won't start
Guys, hi, and thanks in advance for any advice.
So, I am a real noob when it comes to tractors and the internal combustion engine, in general.
I needed something to haul logs from the woods, so a neighbor sold me a 1945ish Ford 9n 6 volt
It ran well enough when I was testing her out. Drove it home. The carb was leaking, I knew this, but was keen to get stuck in and learn a thing or 2. I was busy with house repair, and let the tractor sit for a couple of weeks. Yesterday I took the carb off, gave it a good clean. The float needle seemed a little sticky. I have a new one on order, but reseated it as best I could and so far, the leaking is drastically reduced/addressed
However, when I went to run her, she just wouldn't bite. Starter works, belt drives the shaft, but no spark or explosion, best as I can determine. I put in new 437, and then 216 plugs, for less resistance and a smaller gap. When I hit the ignition with the new plugs, I hear a loud electrical whine the first time, but no crank. It cranks after that first try however.
On 2 occasions, once today and once yesterday it almost coughed into life, very briefly.
I drained the carb, took the plugs out, added some oil to the plug holes, I can feel compressed air coming out of the holes when I turn the ignition on. I even tried warming the plugs with a lighter.
Battery reads at 6.3, so seems fine. It was a new one too, I am told.
So, where do I go from here? What is next on the list of things to try?
I have already looked over one or two threads related to engine flooding and hard starting and tried all I could find from those.
Thanks again guys. Really hoping to get her operational soon. I have many logs to haul!
Benson
So, I am a real noob when it comes to tractors and the internal combustion engine, in general.
I needed something to haul logs from the woods, so a neighbor sold me a 1945ish Ford 9n 6 volt
It ran well enough when I was testing her out. Drove it home. The carb was leaking, I knew this, but was keen to get stuck in and learn a thing or 2. I was busy with house repair, and let the tractor sit for a couple of weeks. Yesterday I took the carb off, gave it a good clean. The float needle seemed a little sticky. I have a new one on order, but reseated it as best I could and so far, the leaking is drastically reduced/addressed
However, when I went to run her, she just wouldn't bite. Starter works, belt drives the shaft, but no spark or explosion, best as I can determine. I put in new 437, and then 216 plugs, for less resistance and a smaller gap. When I hit the ignition with the new plugs, I hear a loud electrical whine the first time, but no crank. It cranks after that first try however.
On 2 occasions, once today and once yesterday it almost coughed into life, very briefly.
I drained the carb, took the plugs out, added some oil to the plug holes, I can feel compressed air coming out of the holes when I turn the ignition on. I even tried warming the plugs with a lighter.
Battery reads at 6.3, so seems fine. It was a new one too, I am told.
So, where do I go from here? What is next on the list of things to try?
I have already looked over one or two threads related to engine flooding and hard starting and tried all I could find from those.
Thanks again guys. Really hoping to get her operational soon. I have many logs to haul!
Benson
41 - 60 of 72 Posts
9N doesn’t have one. It has an ammeter and an oil pressure gauge. That’s all. We are talking 1939 technology here.I'm jumping in here late with a thought. I had a similar experience with a portable generator. The issue I found was a faulty oil pressure sensor. It ran perfectly after replacing. Jim G.
Update!
Put in a new battery, and a new float needle and seat. She wanted to start pretty much right away, but I had do to some dicking with the idle mixture and main adjustment before she fired into life. Drove her about briefly, brought her a stop. Kept fiddling with the adjustments. Managed to keep her running with choke in this time.
There was some back firing it seemed
However, when I let all the throttle off, she eventually sputtered and now won't start again
Put in a new battery, and a new float needle and seat. She wanted to start pretty much right away, but I had do to some dicking with the idle mixture and main adjustment before she fired into life. Drove her about briefly, brought her a stop. Kept fiddling with the adjustments. Managed to keep her running with choke in this time.
There was some back firing it seemed
However, when I let all the throttle off, she eventually sputtered and now won't start again
I also replaced the resistor and cleaned up all the electrical contacts that ran to it.
Do I need to mess with the idle adjustment more do you think? I just set as per recommendations, and did not touch it after that
The idle jet works bass ackwards. In reality it is an air bleed. Turning it in reduces air flow and makes the idle mixture richer. One rule of thumb is to start 1 to 1&1/2 turns out and turn it in until you get a smooth idle without pop-pop-popping in the exhaust. The popping is indicative of too lean a mixture.Do I need to mess with the idle adjustment more do you think? I just set as per recommendations, and did not touch it after that
Sometimes you turn the screw all the way in and you still can’t can’t get rid of the popping entirely. People have been known to drill the hole in the idle jet slightly larger, but I don’t recommend this to the average owner unless you have a machine shop handy to extract a broken drill bit.
The main jet is a simpler proposition. Turn it in until the motor slow as down, then turn it out until the motor slows down. Then turn it halfway between the two settings.
What resistor did you replace?Do I need to mess with the idle adjustment more do you think? I just set as per recommendations, and did not touch it after that
It’s starting to sound to me like there are seriously plugged up passages in that carburetor. Once again, I’d swap it for a rebuilt. When I rebuild one I soak it in carb cleaner for a couple of days, back all of the jets (3 of them) out with screwdrivers ground to fit, rod all of the passages out (welding tip cleaning rods work - cheap at Harbor freight. Then replace everything in the carb except the float. That means new jets and the little brass cylinder that bleeds gasoline into the air stream. I also replace take the flappers off the throttle and choke shafts and inspect the shafts. If worn, I replace them and use new shaft seals, not forgetting to Locktite the screws.Do I need to mess with the idle adjustment more do you think? I just set as per recommendations, and did not touch it after that
It’s starting to sound to me like there are seriously plugged up passages in that carburetor. Once again, I’d swap it for a rebuilt. When I rebuild one I soak it in carb cleaner for a couple of days, back all of the jets (3 of them) out with screwdrivers ground to fit, rod all of the passages out (welding tip cleaning rods work - cheap at Harbor freight. Then replace everything in the carb except the float. That means new jets and the little brass cylinder that bleeds gasoline into the air stream. I also replace take the flappers off the throttle and choke shafts and inspect the shafts. If worn, I replace them and use new shaft seals, not forgetting to Locktite the screws.
OK, I'll be back with updates eventually
Great. 12 volt conversions usually have an aftermarket second resistor. That’s why I’m asking.
make sure that you’re getting a good fuel flow to the carb also. When you take the fuel line off is should pour out, not drip drip drip. Sometimes people cut the line and put in a cheap plastic lawnmower fuel filter that plugs up and restricts the flow. For that matter the screen in the fuel bowl can plug up with rust, too.
fuel flow seems fine.Great. 12 volt conversions usually have an aftermarket second resistor. That’s why I’m asking.
make sure that you’re getting a good fuel flow to the carb also. When you take the fuel line off is should pour out, not drip drip drip. Sometimes people cut the line and put in a cheap plastic lawnmower fuel filter that plugs up and restricts the flow. For that matter the screen in the fuel bowl can plug up with rust, too.
I just replaced the bowl gasket and screen also.
New carb going on today. The old one was leaking like a sieve again. I will report back.
Does anyone have a pic of what a bad coil looks like?
Does anyone have a pic of what a bad coil looks like?
I doubt it is a bad coil if you say that it runs OK choked.
A bad coil is not usually an issue that can be determined via a visual inspection. It is the thin insulation of the individual windings inside the coil that break down over time which causes shorting from one winding to the next, thereby reducing the actual numbers of complete turns of the wire that the current passes through. It is the ratio of the number of windings on the primary of the coil to the number of windings on the secondary that creates the increase in voltage that in turn creates the spark that can jump the gap on the spark plug. Most coils that go bad do so gradually over time, and they work fine at first when cold, and then exhibit problems once they heat up after running for a while. Over time the amount of time that thy will run properly after a cold start decreases until it finally will no longer work even when cold.
In the past, some coils have the windings immersed in an oil or tarry substance, and those can sometimes be determined to be bad when the oil or tar begins to leak, but I don't think that many automotive/tractor coils are built that way thes days, as the oil/tar that was used was usually a PCB, which is now banned due to its carciniogenic properties.
In the past, some coils have the windings immersed in an oil or tarry substance, and those can sometimes be determined to be bad when the oil or tar begins to leak, but I don't think that many automotive/tractor coils are built that way thes days, as the oil/tar that was used was usually a PCB, which is now banned due to its carciniogenic properties.
New carb has made no difference. Same story. I can get her to run more or less first time, under load. Letting off the throttle kills the engine. After that first run, she won't start at all, till the next day, or hours later. A lot of carb valve leakage while trying to turn over the engine also.
New idle adjustment screw is a pain to reach. The old one was finger turnable.
There was a big backfire this morning too.
🤷♂️
New idle adjustment screw is a pain to reach. The old one was finger turnable.
There was a big backfire this morning too.
🤷♂️
I'm gonna take the fuel line off and see if I have a clog, but it does seem to flow well enough. Not convinced this is the problem.
Are these screens replaceable or do I need a whole new valve?
Backfiring is due to unburned fuel in the exhaust system. The only way that unburned fuel can get there is if there is no spark and no ignition in one or more cylinders. The failure to spark can be intermittent - just enough to get raw gasoline vapor into the exhaust manifold and down to the muffler.New carb has made no difference. Same story. I can get her to run more or less first time, under load. Letting off the throttle kills the engine. After that first run, she won't start at all, till the next day, or hours later. A lot of carb valve leakage while trying to turn over the engine also.
New idle adjustment screw is a pain to reach. The old one was finger turnable.
There was a big backfire this morning too.
🤷♂️
I hate to think that the carb issues have been barking up the wrong tree, but ignition failure can be:
badly burned points ( replace points and condenser - cheap fix)
worn out and fouled spark plugs (again, a cheap fix)
very weak coil ($29 on the just8Ns.com website, Tractor Supply may be cheaper)
it’s really easy to flood the system on these tractors by heavy use of the choke, then nearly impossible to restart them unless the tractor sits for a while, but the failure once things warm up points to the coil. There is no easy way of testing the coil. I remember seeing on another website a testing arrangement that someone built using an extra distributor and four spark plugs mounted in a frame but it’s much simpler just to buy a new coil.
when you take the cap off the distributor be sure to wiggle the shaft. I’m serious. There should be no play. I recall someone who had strange operating problems due to badly worn shaft bearings and 8 thousandths side to side play in the shaft.
41 - 60 of 72 Posts
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