Written by: Bruce Haynes

Don’t you just hate it when one of your favorite mechanical tips is poofed into myth status? It’s like the stages of death…….. denial, anger, bargaining, depression and acceptance……..when that cherished belief is taken away. Ever since childhood, you had been told time & again never to place a car battery on a concrete floor because it would drain the current out of it. Well, that was true of the early wet cell batteries with wooden cases used as late as 1925. Putting an automotive battery on a concrete floor won’t hurt it a bit.

So here it is again.

Here are a few more N Ford tractor myths we can assign to the “dustbin of history”:

MYTH: Because zinc has been removed from engine oil, you must add it to protect the flat tappets in an N engine.

The current level of phosphorous (the anti-wear element is not zinc – it is the phosphorus that comes with the zinc in the ZDDP additive) is more than adequate for the valve train on a 23HP low RPM flat tappet engine with 30# valve spring pressures. It is also a little higher than the levels you would have found in the vast majority of 1940-1960 engine oil formulations. The truth is most “old school” flat tappet production engines are perfectly happy at 600-800 PPM phosphorous. And if you have a “high performance” engine that actually needs a higher level of phosphorous you don’t have to go to diesel oils to get it. The SL/SM service class limits on zinc/phosphorous only apply to viscosity grades SAE xxW20 and xxW30. An SAE xxW40 grade SL or SM service class oil can have as much as 1400 PPM. Anything much more than that and the zinc and phosphorous will start to chemically eat the metal away accelerating camshaft and tappet wear. So make sure you understand the chemistry and be mighty careful what you are adding to your oil.

MYTH: If you convert your side distributor 8N to 12 volts, make sure you get a 12 volt coil with an internal resistor.

FACT: No automotive coil has an “internal resistor”. Internal coil resistance is determined by wire gauge and the number of turns. Higher resistance is provided by smaller gauge wire with greater turns. If the coil is marked or sold with a notice “requires an external resistor” that simply means it has a low internal resistance and will be damaged by excessive voltage. It does not mean the coil has an internal resistor.

MYTH: If your engine is overheating, remove the t-stat.

FACT: The purpose of the t-stat is to quickly get the engine to it’s optimum operating temp and keep it there. The most common reason for an N to “over heat” is over filling the radiator. Only add enough fluid to cover the core. Do use a thermostat. If you don’t the engine heats unevenly, which means it wears unevenly. A cool-running engine does not heat the oil sufficiently and you will get sludge build-up in the pan as a result. Further, water will remain in the oil because the oil never gets hot enough to evaporate the water; that creates acids in the oil leading to bearing corrosion. N tractors came from the factory in 1939 with a 160-degree thermostat. Ford added t-stats to cars in 1933.

MYTH: The t-stat lows the coolant down so that the radiator has time to remove the heat from the coolant. If it passes at too high a rate it does not have time to cool.

FACT: There are a number of perfectly valid reasons to use a t-stat; slowing the flow of the coolant isn’t one of them. Unfortunately it is one of those pervasive internet myths that survive and grow because it makes some sort of intuitive sense to many people. Newton’s basic Law of Cooling and how it works in an automotive engine is a bit less intuitive.

The rate of heat transfer into and out of the coolant is independent of flow rate. Factors like cavitation and turbulence caused by higher flow rates can affect that but in general rate of heat transfer is independent of coolant velocity. The amount of heat transferred in any single round trip is proportional to the time the coolant takes to traverse the system. Faster moving coolant transfers less heat per trip but makes more trips per unit time so “cooling” is the same.

In simple words the rateof heat transfer is proportional to the difference in surface temperatures of the coolant and the object being cooled/heated. The longer the objects stay in contact the closer their temperatures become and the rate of heat transfer between them is reduced. Speed up the coolant flow and the rateof heat transfer increases. Add to that the beneficial effects of turbulence (fast) versus laminar (slow) coolant flow and the physics of engine heat transfer gets even less intuitive.

MYTH: I think the solenoid on my 9N is defective.

FACT: 2 and 9N’s did not come from the factory with solenoids. They all had mechanical starter switches. When you press the starter switch, it pushes a piece of linkage into the switch which manually closes the contacts and completes the circuit. Unlike a solenoid which electrically closes the contacts and completes the circuit.

MYTH: Use 30 weight non-detergent oil in your engine because that’s what the owner’s manual recommends.

FACT. The owner’s manual was written in the early 1950’s. Much has changed for the better in petroleum products in the past 60 years. Pick the weight of the engine oil by the condition of the engine (oil pressure) & the outside temperature. A straight weight oil is probably ok in a hot climate, but you will get excessive engine wear on startup in cold climates. (That’s one reason multi-vis oil was invented) A worn engine is going to need a heavier weight oil to maintain oil pressure at operating speed & temp. Switching to detergent oil is not going to loosen up the sludge in the engine. Stirring up the sludge is chemically impossible. The detergent in the oil is going to pick up the pollutants in the oil and deposit them in the filter. HD oil is not an engine flush or cleaner. Further, if there was any danger of the HD oil causing problems in engines having previously used ND oil, that warning would be all over the oil container.

MYTH: The 60+ year old engine in an N requires lead in the gas.

FACT: It is not necessary to add lead to the gas or use hi-test gas. Or to use ethanol free gas. This is a low compression (6.5:1) low hp (23 hp) engine with hardened valve seats. Regular gas with no additives works just fine. But, if you leave gas in the tank for more than 30 days, a fuel stabilizer is a good idea. Stabil is a good product as is Star Tron.

MYTH: If your shifter boot is worn or missing, water will get into the hydraulic sump.

FACT: Contrary to conventional wisdom, not a lot of water gets in the oil from the shifter boot. Of course, if it’s bad, replace it, but you get water from the draft control spring & the dipstick. But, most water is just a byproduct of the heating/cooling cycle of the oil. The oil never gets hot enough (like engine oil) to boil off the water and it condenses inside the case. And, even when you aren’t operating the tractor, the oil and case heat and cool at different rates, also creating condensation. The purpose of the shifter boot is to keep dirt out of the hydraulic sump.

MYTH: Installing the dust boot on the gear shift can be a real chore.

FACT: Yes it can if you get the wrong boot. One size does NOT fit the 9/2N as well as the 8N. The part number for the 2/9N boot is 9N7277. The part number for the 8N boot is 8N7277 .

MYTH: On a hot day, your engine can vapor lock.

FACT: In order to vapor lock in a fuel line, the engine must have a fuel pump. Without a fuel pump and having the carb exposed to outside air, vapor lock on an N just isn’t going to happen. However, if the tank vent gets clogged, the engine can vacuum lock. And, if you are using winter blend ethanol gasoline on a very hot summer day, it is possible to boil the fuel in the tank.

MYTH: The freeze or frost plugs in an engine are there to pop out and protect the block from cracking if the coolant freezes.

FACT: Core plugs are used to fill the sand casting core holes found on water-cooled internal combustion engines. They are also commonly called frost plugs, casting plugs, freeze plugs, or engine block expansion plugs. Sand cores are used to form the internal cavities when the engine block or cylinder head is cast. These cavities are usually the coolant passages. Holes are designed into the casting to support internal sand forms, and to facilitate the removal of the sand after the casting has cooled. Core plugs are usually thin metal cups press fitted into the casting holes, but may be made of rubber or other materials. They are not designed to protect the engine block from cracking if the coolant freezes.

MYTH: My test light comes on and my starter turns, so my battery must be ok.

FACT: You can string flashlight batteries together and get 12 volts; will that start your tractor? This is where a digital volt meter and a hydrometer comes in handy. A fully charged battery should read 6.32 volts with specific gravity at 1.265 in each cell. A battery at 50% charge will read 6.12 volts with a specific gravity of 1.190. And, at 6.03 volts and a specific gravity of 1.155, you only have a 25% charged battery. You need a strong battery to close the solenoid, spin the starter, engage the Bendix and provide voltage to the coil. As the battery gets weaker, the first thing to fail is your spark. If the battery is almost totally dead, all you will hear is the solenoid clicking. The more current you use to spin the starter, the less you have for the ignition.

MYTH: If you reverse the battery cables, the starter will turn backwards.

FACT: No, it won’t turn backwards. The design is such that reversing the applied voltage reverses the magnetic fields of BOTH the armature AND the field coils, thus it still turns in same direction. It would need to be internally re-wired so as to reverse the magnetic field of EITHER the armature OR the field coils in order to reverse the rotation. However, if you reverse the battery cables on your alternator or EI, you will end up with door stops.

MYTH: Always use 90w mineral oil in your hydraulics because that is what was recommended in the owner’s manual.

FACT: The owner’s manual was written in the early 1950’s. Just like with engine oil, much has changed for the better in petroleum products in the past 60 years. The original recommendation was EP Gear Oil conforming to Ford specification M-4864-A and B, SAE 80 below +32 degrees F, and SAE 90 above +32 degrees F. (Do you want to change your hydraulic fluid every spring and fall? ) However, the new recommendation from the local Ford-New Holland dealer now recommends Ambra Multi-G 134 (NH-410B) synthetic fluid. Some people stick with the original spec and use 90w mineral oil. The modern equivalent of 90w mineral oil is TSC Traveler brand GL-1 or NAPA part number 65-205. Those may be less expensive, but the Multi-G 134 synthetic is good from -5 to 120 degrees F! CNH sells a product called Ambra 134D that conforms to that specification. The equivalent product (and less expensive) from TSC that meets Ford spec M2C-134d is their Universal Tractor Fluid. Neither of these products are SAE 90 gear oil – they are multi-purpose oils with an exceptionally high viscosity index engineered specifically for this type of application. The TSC product labeled “Ford Tractor Oil” is a plain SAE 90 gear oil. The M2C-134D type product has a slightly lower viscosity when hot – about the same as SAE 80 gear oil – so if your 8N hydraulic system is worn it may reduce lift capacity somewhat. On the other hand because of its much higher viscosity index it doesn’t thicken nearly as much when cold which makes it a better performer in winter conditions. Personally I use the TSC UTF product year round in the common sump systems on all my tractors. They all lift strong and hold without leak down. And the hydraulic system is nice and responsive even when the oil is dead cold – especially important on the 8N with front loader.

MYTH: If you try to jump start a 6 volt tractor with a 12 volt battery, you will burn up the points and condenser.

FACT: No you won’t. Points and condensers in these tractors operate just fine on 6 or 12 volts. If they did not, there would be separate part numbers for points and condensers based upon ignition voltage.

MYTH: If your tractor won’t start and the plugs are dry, that means gas isn’t getting to the cylinders; put a few tablespoons of gasoline in each cylinder.

FACT: All that accomplishes is washing the oil off of the cylinder walls thereby reducing compression, And while the gas will probably evaporate before you can get the plugs reinstalled, if it doesn’t, raw gasoline will foul the plugs. Spark plugs are supposed to be dry; if they are wet, you have flooded the engine. And fouled the plugs. If you have reason to believe that fuel is not getting to the cylinders, use starting fluid. No, starting fluid used correctly will not blow up your low hp, low compression gasoline engine.

MYTH: If you can’t find your feeler gauge, use a dime to set the point gap.

FACT: The point gap on a front distributor is .015; it’s .025 on a side distributor. A dime is .053. Do the math. Do you want your points open more than 3 times greater than spec on the front distributor, or just twice as far on the side distributor?

MYTH: If your tractor won’t start on 6 volts, install an 8 volt battery.

FACT: You need 9.5 volts to charge an 8 volt battery; your generator puts out 7.5 volts to charge the 6 volt battery. Trying to charge an 8 volt battery with 7.5 volts gets you a perpetually discharged 8 volt battery operating at about 50% capacity. Adjusting the 8N voltage regulator to put out 9.5 volts requires special tools and expertise to do it correctly. Or, you can try it yourself as long as you are prepared for the consequences of failure: a boiled battery, a burned up v/r or no charge at all. Cranking up the output on a 2 or 9N generator will increase the charging voltage but at the cost of overheating the generator. Having a partially discharged 8 volt battery in your tractor is no better than having a fully charged 6 volt battery. At 8.43 volts, your 8v battery is fully charged. And it needed 9.4 volts to get there. But, at 8.04 volts, your 8v battery is only 25% charged. In other words, it’s no better than a 6v battery at that point. If you already have an 8v battery and the v/r was adjusted to put out 9.5 volts, chances are very good that it is no longer doing that. Because the adjustment was made by bending the points arm. Is that how ignition points are adjusted? You will also need to keep checking your voltage output every few months because it will change with both time and temperature. Remember, it’s only about 2 volts that makes the difference between no charge and a boiled battery.

IMHO……cleaning up the grounds, replacing the cables and buying a new 6v battery is a lot easier.

MYTH: You can tell the year of your tractor by the serial number. The numbers are lightly stamped (not raised) on the left side of the block, below the head & behind the oil filter canister.

FACT: You can tell the year of your ENGINE by the serial number. Engines are interchangeable between the 2, 9 & 8N’s. Many replacement engines do not have serial numbers. To better ID the year of the tractor, check out this website: http://www.oldfordtractors.com/idhistory.htm

MYTH: Make sure your hydraulic fluid is “yellow metal safe” because your pump has yellow metal in it.

FACT: The yellow metal issue arose decades ago with GL-5 oil in synchro-mesh transmissions where the high level of EP additives combined with the high operating temperatures on the surface of the synchronizers caused accelerated erosion of the brass. That problem has been blown up into a general problem with yellow metals which it never was. And even the synchronizer problem is pretty much old news.

Most modern GL-5 formulations use buffered sulfur compounds that have much higher activation temperature, contain no chlorine, and are safe in many synchro-mesh transmissions. They even pass the GL-4 yellow metal corrosion test that is designed to ensure the oil is safe for use in synchro-mesh transmissions.

There is no problem with most GL-5 oil in an N-series. The only yellow metal in the N-series sump is the PTO cam blocks and the surface temperature on them doesn’t begin to approach the activation temperature of either the old or new EP additives. The yellow metalissue with regard to N-series hydraulics is simply a myth that won’t die.

MYTH: All 6 volt vehicle batteries are manufactured positive ground. If you hook it up negative ground, you will damage the plates.

FACT: Yet another internet myth propagated by folks who have never worked on or owned pre-1956 vehicles when nearly all were 6 volt, but the battery polarity was unique to the manufacturer. And no 6 volt battery was or is sold based upon its use polarity. For example, 6 volt negative ground cars were Chevy’s, Buick’s and Pontiac’s. 6 volt positive ground vehicles were Fords, Dodges & Chrysler’s. No battery is built positive or negative ground. All batteries have positive and negative posts; it’s the INSTALLATION of the battery in the vehicle which makes the circuit positive or negative ground. Just look at the battery; find the positive post (it’s larger and marked POS or +) Trace the cable. If the cable goes to the chassis, the vehicle is positive ground. If it goes to the starter switch or solenoid, it’s negative ground. Do NOT rely on the color of the cable. Because electrons are color blind.

MYTH: No spark? It’s the coil.

FACT: Odds are pretty good it’s not. The number one cause of a weak or no spark is a weak battery. And there are a few more likely causes than a failed coil. For starters, round coils are pretty robust & square coils aren’t (because of the difference in insulation used), but neither one will hold up to a poorly done 12v conversion that allows too much current to the coil or leaving the key on. Too much current creates heat which melts the insulation. Insufficient resistance in a 12v conversion will do the same thing. Rarely do coils just “go bad.”

I’ll venture a guess that 75% of new N coils sold today are sold to folks who do not understand how to diagnose a poor spark problem or how a coil works. So, for those who don’t know any better, in a no spark situation the first suspect is usually the coil……and, more often than not, it isn’t the problem. Or as a friend humorously suggested: “Well, it is like this…I don’t know or really understand what that black thing does & I am suspicious of the unknown, so I think the problem is the black thing.”

About 5 years ago, my neighbor proudly told me about fixing his 8N. Seems like it wouldn’t start, so he replaced the coil. Tractor started, problem solved. I asked him if I could have the old coil. He gave it to me. I put it on one of my 8N’s where it has been ever since.

I do not know why his tractor would not start. I do not know why it did start and ran fine after he put a new coil on it. Sure, I can make a lot of guesses, but we will never know for sure.

But I do know he did not have a bad coil.

MYTH: If your tractor serial number is preceded by a diamond, that means the engine has cast iron sleeves. If it’s a star, it has steel sleeves.

FACT: No, those symbols will not tell you what sleeves (if any) are CURRENTLY in your engine. They tell you what sleeves were in the engine when it left the factory……prior to 1953!

MYTH: Check your sediment bowl to see if you have any gas in the tank.

FACT: Nope, it doesn’t work like that. The sediment bowl will be completely full and the tractor can be out of gas. Next time you go to turn your tractor off, turn the fuel off while the engine is running. When it sputters to a stop, look at the sediment bowl. It will be full. Remember, this is a gravity fuel system!

MYTH: If your tractor is hard to start, put electronic ignition (EI) on it.

FACT: Many times a tractor that’s hard to start on points will be just as hard to start on EI if the hard starting problem wasn’t the points. All EI does is replace the points and condenser. EI does not give you higher spark voltage, eliminate all maintenance on your ignition system or give enough of a horsepower boost to cause the tractor to do wheelies. It replaces the points. That’s it. It will not correct or overcome other major problems in the ignition system. While it may give you more HP or improve fuel economy, both would be so insignificant as to be hardly noticeable on a 23 hp engine. As the analogy goes, putting EI on a 65+ year old tractor is like putting 12” woofers on your grandfathers 78 rpm Victrola and expecting it to sound like surround sound. While it is certainly true that EI is superior when compared to points ignition systems, that’s beside the point. The question is the practical applicability of EI on a 65+ year old 23 hp, low compression, low rpm tractor engine. The key advantage to EI is that you do not need to gap & lube the points every year & replace them every 4 or 5 years or. If you perform annual maintenance on the points & change them every 4 years or so using quality parts, you will see no difference whatsoever between a points ignition system & EI on an N. The key disadvantages to EI on an N are initial cost, nearly impossible for the average N owner to repair, will not work w/ low battery voltage, & easily damaged beyond repair by polarity reversal & other common mistakes If you have a well running tractor & just don’t care to fool w/ points anymore, EI is a perfect alternative. If you expect EI to cure any significant ignition problem you may have other than bad points, it won’t. Bottom line……….this is the question you need to answer: “If tens of thousands of other N’s operate just fine on 6v and points, why can’t mine?”

MYTH: No need to buy new oil for your N tractor; just save the oil from your vehicle oil change and use that in your N.

FACT: No, this isn’t a joke. When I first saw this on a tractor board, I thought the poster was trolling us. He was dead serious and got in quite a huff when more than one person told him that this was a really, really stupid idea.

MYTH: No spark at the plugs on your tractor? Polarize the generator.

FACT: Nope. If your tractor isn’t showing a charge on the ammeter, polarize the generator. The generator and v/r have nothing to do with spark at the plugs.

MYTH: “An old farmer told me………”

FACT: Consider any thing you hear beginning with that phrase the same as “ Once upon a time”. If age and turning dirt resulted in wisdom, I’d be a genius. There is a difference between 50 years of experience and 1 year of experience repeated 50 times.

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