12 chane over 8n

[1956 chevy]

12 volt alt has a small v pully do i use or find big v pully

 

[Non-farmer]

You need to get a pulley for a 5/8" belt.

 

[Jim.ME]

You need to get a pulley for a 5/8" belt.

He needs a small diameter pulley for a 5/8" wide vee belt.

 

[YosmiteSam]

I would use an A cross section belt. There is no such thing as a 5/8 wide belt, a B cross section belt is 21/32 wide, that is 1/32 more than 5/8.

If an A cross section belt fits the alternator use it. Old engine pulleys tended to have wider vees than the belts actually need so that the belt fit down well into the groves. Newer pulleys are visually a bit smaller in the vee because it turned out that extra bit of diameter didn't help keep belts on. By trimming down the design they save a bit of steel when they make them.

A cross section belts are often labeled as 4L belts, both are 1/2 inch wide. Use them interchangeably. The difference to pay attention to is that A belts are measured by inside diameter, and the 4L system uses outside diameter, or vise versa. So mind the length. The difference between inside to outside measurement of length amounts to about an inch.

In the A and B system the length in inches is the number which follows the A, or B. For the 4L system the length of the belt are the two center numbers of 4 numbers which follow the 4L.

 

[Jim.ME]

I would use an A cross section belt. There is no such thing as a 5/8 wide belt, a B cross section belt is 21/32 wide, that is 1/32 more than 5/8.

If an A cross section belt fits the alternator use it. Old engine pulleys tended to have wider vees than the belts actually need so that the belt fit down well into the groves. Newer pulleys are visually a bit smaller in the vee because it turned out that extra bit of diameter didn't help keep belts on. By trimming down the design they save a bit of steel when they make them.

A cross section belts are often labeled as 4L belts, both are 1/2 inch wide. Use them interchangeably. The difference to pay attention to is that A belts are measured by inside diameter, and the 4L system uses outside diameter, or vise versa. So mind the length. The difference between inside to outside measurement of length amounts to about an inch.

In the A and B system the length in inches is the number which follows the A, or B. For the 4L system the length of the belt are the two center numbers of 4 numbers which follow the 4L.

It would be best to use the proper automotive belt to fit the crank and water pump pulleys. The OEM part numbers (9N8620B (5/8" x 45-1/2") and 8N8620 (5/8" x 41-5/8") cross to Gates belts that have a top width of 5/8". The angles will be different from letter series belts. Running a narrow belt in wide pulleys lead to wear, the belts bottoming out in the OEM pulleys and slipping. JMHO

 

[Non-farmer]

N tr

I would use an A cross section belt. There is no such thing as a 5/8 wide belt, a B cross section belt is 21/32 wide, that is 1/32 more than 5/8.

If an A cross section belt fits the alternator use it. Old engine pulleys tended to have wider vees than the belts actually need so that the belt fit down well into the groves. Newer pulleys are visually a bit smaller in the vee because it turned out that extra bit of diameter didn't help keep belts on. By trimming down the design they save a bit of steel when they make them.

A cross section belts are often labeled as 4L belts, both are 1/2 inch wide. Use them interchangeably. The difference to pay attention to is that A belts are measured by inside diameter, and the 4L system uses outside diameter, or vise versa. So mind the length. The difference between inside to outside measurement of length amounts to about an inch.

In the A and B system the length in inches is the number which follows the A, or B. For the 4L system the length of the belt are the two center numbers of 4 numbers which follow the 4L.

N tractors use a B belt. What you accurately describe as 21/32nds is standardly referred to as 5/8". I can produce countless citations from both manufacturers and vendors to support that reference. A half inch belt - your A belt - is wrong for an N tractor because it is too narrow for the pulleys on the N crank and water pump. He needs a B belt - the length of which will vary depending on the specific conversion kit he gets, because of the variety of alternator mounts. I ended up replacing the belt that came with my kit due to length issues. The one supplied forced me to remove all alternator bolts, including the pivot bolt, put the belt on and then bolt up the alternator. When that was done, the alternator was in physical contact with the manifold, something I didn't care for. So I got a longer belt. An A belt is wrong, every time. It is too narrow for the N pulleys and will bottom out in them.

 

[Non-farmer]

It would be best to use the proper automotive belt to fit the crank and water pump pulleys. The OEM part numbers (9N8620B (5/8" x 45-1/2") and 8N8620 (5/8" x 41-5/8") cross to Gates belts that have a top width of 5/8". The angles will be different from letter series belts. Running a narrow belt in wide pulleys lead to wear, the belts bottoming out in the OEM pulleys and slipping. JMHO

I'm running a Gates B42 now. Never slips.

PS: don't want to get into a hair-splitting contest in terms of B belts versus the ones you described. I just know a B belt works fine and an A belt is simply wrong

It doesn't matter if the A belt fits the alternator pulley, it will NOT fit the engine pulleys. That's why you replace the alternator pulley. (Jim, I know you know this already)

 

[YosmiteSam]

It would be best to use the proper automotive belt to fit the crank and water pump pulleys. The OEM part numbers (9N8620B (5/8" x 45-1/2") and 8N8620 (5/8" x 41-5/8") cross to Gates belts that have a top width of 5/8". The angles will be different from letter series belts. Running a narrow belt in wide pulleys lead to wear, the belts bottoming out in the OEM pulleys and slipping. JMHO

I guess I've been doing it all wrong for the last 50 years. I've been pulling A cross section V-belts off of my service trucks stock, or getting them at a bearing supply when I needed an automotive belt for all of my working life.

Saved a lot of money over the years because I could buy an industrial A belt for a 1/3 or less than a dealer or retail parts store automotive belt. When belts cost about 6 dollars retail I could buy them for about 2 dollars. Hardware stores tend to carry the 4L belts and they usually cost less than say a NAPA parts house. They last just as well as the others.

The bottom of Ford pulleys, all I have ever seen have a very deep and narrow vee, and A or 4L belt will not bottom out, not even close. And the angles are not different, not enough to notice anyway if there is a very slight difference in angle. I don't think there is a difference in angle.

Considering the limited use a tractor gets from anyone but a farmer, compared to the hours a car gets, no vee bilt is ever going to wear out on a hobby tractor. When one needs replacement it's because it was weathered and it rotted over the years.

 

[wore out]

I guess I've been doing it all wrong for the last 50 years. I've been pulling A cross section V-belts off of my service trucks stock, or getting them at a bearing supply when I needed an automotive belt for all of my working life.

Saved a lot of money over the years because I could buy an industrial A belt for a 1/3 or less than a dealer or retail parts store automotive belt. When belts cost about 6 dollars retail I could buy them for about 2 dollars. Hardware stores tend to carry the 4L belts and they usually cost less than say a NAPA parts house. They last just as well as the others.

The bottom of Ford pulleys, all I have ever seen have a very deep and narrow vee, and A or 4L belt will not bottom out, not even close. And the angles are not different, not enough to notice anyway if there is a very slight difference in angle. I don't think there is a difference in angle.

Considering the limited use a tractor gets from anyone but a farmer, compared to the hours a car gets, no vee bilt is ever going to wear out on a hobby tractor. When one needs replacement it's because it was weathered and it rotted over the years.

There's a LOT of difference between an automotive belt and a cheap FHP belt, but, what the heck, if what you've been doing works for you GO FOR IT!

 

[YosmiteSam]

There's a LOT of difference between an automotive belt and a cheap FHP belt, but, what the heck, if what you've been doing works for you GO FOR IT!

I said would use an industrial A belt, I said FHP belts would fit, and would work. Both are up to the task, a tractors fan and alternator is a fraction HP load. A cross section belts are just a durable, or more durable. They are used on equipment which runs 24/7 for the life ot the machine.

4L belts are a bit lighter than an A, but even they meet the load. a 3L would be a bit overloaded but a 4L fine. Both 3L and 4L are fractional HP belts but the fan and alternator of an 8N is a fractional load as well, so it is fine.

I asked Twitters artificial intelligence about that, and this is the AI's take on that, I asked it how much hp does the fan and generator draw from the engine of a ford 8N tractor? This is it's answer:






The Ford 8N tractor, produced from 1947 to 1952, is equipped with a 2.0L 4-cylinder gasoline or distillate engine. To determine how much horsepower (HP) the fan and generator draw from the engine, we need to consider their mechanical and electrical loads. Here’s the analysis based on available information and reasonable estimates:
Ford 8N Engine Horsepower

• Engine Output: The Ford 8N's engine produces approximately 27.4 HP at 2000 RPM (rated engine horsepower).
  
  
• PTO Horsepower: The claimed PTO horsepower is 27.32 HP, with tested figures around 23.24 HP.
  
  
• Drawbar Horsepower: The claimed drawbar horsepower is 23.16 HP, with tested figures around 21.95 HP.
  
  These figures indicate that the engine's total output is partially consumed by parasitic loads (like the fan and generator) before delivering power to the PTO or drawbar.

Fan Horsepower Draw
The cooling fan on the Ford 8N is a 6-blade fan driven by a belt connected to the engine's crankshaft. The horsepower required to drive a cooling fan depends on its size, speed, and the airflow it needs to produce. For small tractors like the 8N:

• Typical cooling fans for engines of this size (120 cubic inches, ~2.0L) require 0.5 to 2 HP to operate, depending on engine RPM and load conditions.
• The Ford 8N fan, being relatively simple and designed for a low-RPM engine (max 2000 RPM), likely consumes ~0.5 to 1 HP under normal operating conditions. This estimate is based on general engineering data for belt-driven cooling fans in similar-sized engines, as specific data for the 8N fan is unavailable in the provided references.

Generator Horsepower Draw
The Ford 8N typically uses a 6-volt generator (e.g., models like 8N10001 or FAC10002A) to charge the battery and power electrical components. The generator's power draw depends on its electrical output and mechanical efficiency:

• Electrical Output: A typical 6-volt generator for the 8N produces around 20-30 amps at 6 volts, equating to approximately 120-180 watts (0.16-0.24 HP, since 1 HP = 746 watts).
• Mechanical Efficiency: Generators are not 100% efficient due to mechanical and electrical losses (friction, heat, etc.). Assuming an efficiency of ~70-80%, the mechanical power required to drive the generator is roughly 0.2-0.35 HP.
• Additional Considerations: The generator only draws significant power when charging the battery or powering electrical loads (e.g., lights). At idle or low electrical demand, the draw is minimal, closer to 0.1-0.2 HP. Issues like a short in the generator can increase the load, but this is not typical operation.

Total Horsepower Draw

• Fan: ~0.5 to 1 HP
• Generator: ~0.2 to 0.35 HP
• Combined Draw: Approximately 0.7 to 1.35 HP under typical operating conditions.

 

[YosmiteSam]

This AI thing is fun. I asked it to tell me what I would need to do what I did about a month ago, something I know the solution to, I want to see how well the AI will do. It's 1/3 the topic of this thread. I asked Grok:

Grok since you answered that last question so thoroughly I will now ask you to figure out what voltage regulator, and ballast resistor applied to the field winding I could use to convert a 6 volt positive ground generator (e.g., models like 8N10001 or FAC10002A) to a 12 volt negative ground?

Grok replies:


Understanding the request

• The request is about converting a 6-volt positive ground generator to a 12-volt negative ground system. They're looking at models like 8N10001 or FAC10002A.

Searching for "convert 6 volt generator to 12 volt"


Converting 6 volt to 12v without replacing generator using 6 volt generator - YouTube
www.youtube.com

Convert 6 Volt Generator to 12 Volt - Restoration and Repair Tips Forum - Yesterday's Tractors
forums.yesterdaystractors.com

• Web search shows forums and videos discussing 6-volt to 12-volt generator conversions. It's helpful to see practical advice and step-by-step guides.
• Converting involves replacing field coils with 12-volt ones and using a 12-volt voltage regulator. This seems like a key step to get the system working.
• I'm considering how a ballast resistor fits into this, especially for the field winding. It might limit current, but let's explore more.
• Changing polarity from positive to negative ground means reversing connections. The generator needs repolarizing for this to work right.

Searching for "ballast resistor in generator conversion from 6v to 12v"

• Ballast resistors are often discussed for ignition systems, like reducing voltage for a 6-volt coil in a 12-volt setup. For instance, hotrodwires.com mentions using a 12V ignition ballast resistor specific to the vehicle brand HotRodWires.
• Yesterday's Tractors forums also talk about using a ballast resistor with a 6-volt coil to prevent burning points. It's interesting how it applies there, but not directly for the generator's field winding.

• Search results don't directly address using a resistor in the field winding for generator conversion. Most focus on ignition systems or general

Browsing forums.yesterdaystractors.com for "how to convert 6v generator to 12v with resistor"

• Using a resistor for the field winding isn't standard for converting a 6V generator to 12V. The generator needs rewinding for 12V or replacing, as applying 12V can damage it with excessive current and heat Yesterday's Tractors.
• The user's idea might be to limit current with a ballast resistor when operating at 12V. If the field winding is for 6V, 12V would double the current, risking overheating.

Evaluating resistor use

• To prevent overheating, add a resistor in series with the field winding. This reduces the voltage across it to 6V from a 12V supply.
• The series resistor should match the field winding's resistance. For the 8N10001, that's around 3.2-3.8 Ohms, based on typical values.
• I'm checking if this approach is correct. For a 3.5 Ohm field winding, a 3.5 Ohm resistor at 1.71A would drop 6V, which seems right.
• Applying 12V to a 6V field winding doubles the current and quadruples the heat. This can damage the insulation, so it's risky without proper conversion.

Considering voltage regulator

• The voltage regulator controls field current to regulate output voltage. For 12V, it needs to maintain 12V, not 6V like the original.
• Earlier searches mention replacing the voltage regulator with a 12V unit for conversions. For example, restore-an-old-car.com says you need a 12V regulator Restore.

Searching for "voltage regulator for Ford 8N 12v conversion"

• Voltage regulators are available for Ford 8N tractors, both for 6V and likely for 12V conversions. I'm finding options like Steiner Tractor Parts, but they mostly list 6V regulators with mounting plates.
• Most conversion kits replace the generator with an alternator, which has an internal regulator. This isn't what the user wants, though.
• I'm looking into 12 volt voltage regulators for generators used with Ford 8N. Generators typically use external regulators, unlike alternators with internal ones.
• For a converted generator, we need a 12-volt external voltage regulator that fits the generator's specs. I'm thinking about whether it's an A-circuit or B-circuit generator.

Clarifying circuit type

• Ford N-series tractors likely use A-circuit generators, where the regulator grounds the field. The Brillman Company listing confirms this for positive ground systems Brillman.
• I'm checking if this changes for 12-volt conversions. It seems the circuit type stays the same, just the voltage rating differs.

Searching for "voltage regulator for Ford tractor 12 volt"

Ford Tractor Voltage Regulator - Yesterday's Tractors
www.yesterdaystractors.com

Ford 3000 Voltage Regulator - 12 Volt - D0NN10505A
www.yesterdaystractors.com

• From these results, I can see that there are voltage regulators specifically for Ford tractors with 12-volt systems, such as the Ford 3000, 4000, etc.
• Steiner Tractor Parts mentions a "12 Volt Voltage Regulator" for models like NAA, 600, 700, likely with 12-volt systems. This could fit the user's needs.

Searching for "using resistor for field winding in generator conversion 6v to 12v

• From these results, there's still no direct mention of using a resistor for the field winding in generator conversions. Most results are about general voltage conversion or other topics.

Calculating resistor value

• The user might want to avoid rewinding and use a ballast resistor. I'm figuring out how to calculate the resistor value for this.
• For a 3.5 Ohm field winding, a 3.5 Ohm resistor drops the voltage to 6V with 12V supply. This seems like it could work, but let's see.

Searching for "12 volt A-circuit voltage regulator for generator"

• From this search, Amazon lists a "12 Volt Generator Voltage Regulator Compatible With Delco Agricultural 1118981 1118988," and it's A-circuit.
• This regulator could work for the converted Ford 8N, assuming connections match. It's for Delco, but the circuit type fits.
• Ford NAA tractors from 1953-1954 were 6-volt, but later models like 600 and 800 series from 1955 used 12-volt systems. These likely used A-circuit regulators, fitting the user's needs.

Researching compatible regulators

• Yesterday's Tractors lists part numbers like C5NF10505B for 12-volt regulators. These are for Ford models from 1955 to 1964, likely matching the user's needs.
• Ford switched to 12-volt negative ground systems with the Hundred series in 1955. Regulators for those models should work for the converted 8N.
• Standard conversion involves rewinding the generator and using a 12-volt regulator, so a ballast resistor isn't necessary. Still, I can calculate it if needed.
• Perhaps they are considering using the resistor as part of the conversion. I'm thinking about explaining both options to cover all bases.
• First, have the generator rewound for 12 volts and use a 12-volt negative ground A-circuit regulator, like those for Ford 600, 800 series.
• Steiner Tractor Parts has a "12 Volt Voltage Regulator" for Ford, part number FDS1500, for models like 600, 800. This could be a good fit for the user's conversion.
• Amazon and eBay also offer voltage regulators for Ford tractors. I'm suggesting they look for ones designed for 600 or 800 series with generators.
• Using a 12-volt regulator for negative ground means polarizing the generator correctly. You can do this by momentarily connecting the battery to the armature terminal.
• Changing to negative ground involves updating the battery and other components, like lights and the ignition coil. This ensures everything works with the new system..
• Therefore, I can recommend using a voltage regulator like the FDS1500 or equivalent.
• For the ballast resistor, if needed, it's not standard, but they can use a 3.5 Ohm, 10W resistor.

Completed


I chose and used that same voltage regulator, FDS1 500

I calculated for and used a 1.8 Ohm ballast resistor, that's also the same value resistor I used on the 12 volt coil. Its a standard part.

I did that conversion on the Ford 600 about a month ago, it has 14 hours on it so far and seems to be working fine.

I will analyze Grok's work and figure out why it chose a 3.5 Ohm resistor.

I might find that Grok is right and I am wrong even though I've got an apparent working 12 volt negative ground system on that Ford 600.
BTW GroK used our forum extensively in creating that workup.

 

[OldBlue61]

Man, I hate all this AI crap.

 

[Mad Farmer]

I said would use an industrial A belt, I said FHP belts would fit, and would work. Both are up to the task, a tractors fan and alternator is a fraction HP load. A cross section belts are just a durable, or more durable. They are used on equipment which runs 24/7 for the life ot the machine.

4L belts are a bit lighter than an A, but even they meet the load. a 3L would be a bit overloaded but a 4L fine. Both 3L and 4L are fractional HP belts but the fan and alternator of an 8N is a fractional load as well, so it is fine.

I asked Twitters artificial intelligence about that, and this is the AI's take on that, I asked it how much hp does the fan and generator draw from the engine of a ford 8N tractor? This is it's answer:






The Ford 8N tractor, produced from 1947 to 1952, is equipped with a 2.0L 4-cylinder gasoline or distillate engine. To determine how much horsepower (HP) the fan and generator draw from the engine, we need to consider their mechanical and electrical loads. Here’s the analysis based on available information and reasonable estimates:
Ford 8N Engine Horsepower

• Engine Output: The Ford 8N's engine produces approximately 27.4 HP at 2000 RPM (rated engine horsepower).
  
  
• PTO Horsepower: The claimed PTO horsepower is 27.32 HP, with tested figures around 23.24 HP.
  
  
• Drawbar Horsepower: The claimed drawbar horsepower is 23.16 HP, with tested figures around 21.95 HP.
  
  These figures indicate that the engine's total output is partially consumed by parasitic loads (like the fan and generator) before delivering power to the PTO or drawbar.

Fan Horsepower Draw
The cooling fan on the Ford 8N is a 6-blade fan driven by a belt connected to the engine's crankshaft. The horsepower required to drive a cooling fan depends on its size, speed, and the airflow it needs to produce. For small tractors like the 8N:

• Typical cooling fans for engines of this size (120 cubic inches, ~2.0L) require 0.5 to 2 HP to operate, depending on engine RPM and load conditions.
• The Ford 8N fan, being relatively simple and designed for a low-RPM engine (max 2000 RPM), likely consumes ~0.5 to 1 HP under normal operating conditions. This estimate is based on general engineering data for belt-driven cooling fans in similar-sized engines, as specific data for the 8N fan is unavailable in the provided references.

Generator Horsepower Draw
The Ford 8N typically uses a 6-volt generator (e.g., models like 8N10001 or FAC10002A) to charge the battery and power electrical components. The generator's power draw depends on its electrical output and mechanical efficiency:

• Electrical Output: A typical 6-volt generator for the 8N produces around 20-30 amps at 6 volts, equating to approximately 120-180 watts (0.16-0.24 HP, since 1 HP = 746 watts).
• Mechanical Efficiency: Generators are not 100% efficient due to mechanical and electrical losses (friction, heat, etc.). Assuming an efficiency of ~70-80%, the mechanical power required to drive the generator is roughly 0.2-0.35 HP.
• Additional Considerations: The generator only draws significant power when charging the battery or powering electrical loads (e.g., lights). At idle or low electrical demand, the draw is minimal, closer to 0.1-0.2 HP. Issues like a short in the generator can increase the load, but this is not typical operation.

Total Horsepower Draw

• Fan: ~0.5 to 1 HP
• Generator: ~0.2 to 0.35 HP
• Combined Draw: Approximately 0.7 to 1.35 HP under typical operating conditions.

I don't trust any AI. Humans are on the way to The Terminator secnario........

I get kevlar belts from industrial supply store. Same type of belts my lawn mower decks use.

 

[wore out]

Man, I hate all this AI crap.

It's quickly ruining a once great site, IMHO.

Many of us are attracted to these old machines because of their simplicity and the feeling of going back to an older, simpler time.

Henry Ford was able to build these tractors without AI and, surely we can keep them running without it?

On the other hand if AI can pull me up a wiring diagram of a John Deere 9420 tractor and explain in detail what to look for when the canbus system goes down I;d be more than interested!