| Manufacturer | International Harvester |
| Price | 45,000(USD) |
| Model | 3688 |
| Equipment Type | Row-Crop Tractors |
| Factory | Rock Island, Illinois, USA |
VARIANTS
| 3688 Hi-Clear | high-clearance model |
NEBRASKA TRACTOR TEST 1440 2
| Description | Diesel 16-speed 2WD May 26, 1982 - June 7, 1962 Link: Nebraska Tractor Test 1440 file PTO performance Drawbar performance |
| Power at rated engine speed | 113.72hp / 84.8kW |
| Fuel use | 7.5gal/hour / 28.4l/hour |
| Power at rated PTO speed | 112.48hp / 83.9kW |
| Max power | 99.21hp / 74.0kW |
| Max pull | 12250lbs / 5556kg |
INTERNATIONAL HARVESTER 3688 POWER
| Drawbar (claimed) | 100.2hp / 74.7kW |
| PTO (claimed) | 113hp / 84.3kW |
| Drawbar (tested) | 99.21hp / 74.0kW |
| PTO (tested) | 113.72hp / 84.8kW |
ENGINE DETAIL
The International Harvester 3688 features a robust D436 diesel engine with a 7.1L displacement, delivering reliable performance at a rated RPM of 2400. Its dual dry air cleaner system enhances engine longevity, while a high compression ratio of 16:1 supports efficient fuel combustion, providing strong power for demanding agricultural tasks. However, the engine's weight and size might pose challenges in maneuverability and require adequate torque for optimal performance in various terrains.
| Description | International Harvester D436 diesel 6-cylinder liquid-cooled |
| Displacement | 436ci / 7.1L |
| Bore/Stroke | 4.30x5.00inches / 109x 127mm |
| Air cleaner | dual dry elmeent |
| Compression | 16:1 |
| Rated RPM | 2400 |
| Idle RPM | 900-2400 |
| Starter volts | 12 |
| Coolant capacity | 26qts / 24.6L |
ENGINE OIL
The International Harvester 3688 tractor has an oil capacity of 14 quarts (13.2 liters), which is crucial for optimal engine performance and longevity. Maintaining proper oil levels ensures effective lubrication, reducing wear and tear on engine components. However, it requires regular monitoring to prevent potential engine damage due to low or degraded oil levels, particularly in demanding agricultural scenarios.
| Oil capacity | 14qts / 13.2L |
INTERNATIONAL HARVESTER 3688 ENGINE
The International Harvester 3688 is equipped with a robust 7.1L 6-cylinder diesel engine, providing substantial torque and efficiency for heavy-duty applications. Its advanced hydraulic system enhances lift capacity and responsiveness, making it suitable for both field and loader work. However, maintenance can be a challenge due to the age of the model, necessitating careful sourcing of parts and expertise for optimal performance.
| Description | International Harvester 7.1L 6-cyl diesel |
TRANSMISSION
The International Harvester 3688 features a partial power shift transmission, allowing seamless on-the-go shifting between certain gear pairs without engaging the clutch, which enhances operational efficiency. The 16 forward and 8 reverse gears provide versatility, ideal for diverse agricultural tasks, while the 90-quart oil capacity ensures adequate lubrication, reducing wear and maintaining performance. However, synchronized shifting does require the use of a clutch for specific gear pairs, which may limit rapid gear changes during less favorable conditions.
| Type | partial power shift |
| Gears | 16 forward and 8 reverse |
| Clutch | cerametallic disc |
| Oil capacity | 90qts / 85.2L |
| Description | Left lever selects gear, right lever selects high, low, or reverse range. Tractor may be shifted on the move without the clutch between gear pairs (1-2, 3-4, etc). Synchronized shifting, using the clutch, between gear pairs (2 to 3, 4 to 5, etc). The transmission is four-gear with the powershift provided by an electric solenoid actuated Torque Amplifier |
SPEEDS
| Description | With 18.4-34R1 rear tires |
MECHANICAL
The International Harvester 3688 tractor features a robust 4x4 MFWD option, enhancing traction and stability in diverse terrain, beneficial for challenging agricultural tasks. The hydraulic wet disc brakes provide superior stopping power and durability, which is essential for safety and efficiency during operation. Its 16-speed partial power shift transmission allows for smooth gear changes, offering optimal speed control suited for both fieldwork and transport scenarios.
| Chassis | 4x2 2WD/4x4 MFWD 4WD |
| Steering | power |
| Brakes | hydraulic wet disc |
| Cab | Cab standard with heat and A/C. Optional burgundy or western finish interiors |
| Transmission | 16-speed partial power shift |
CAPACITY
| Fuel | 50gal / 189.3L |
| Hydraulic system | 22.5gal / 85.2L |
HYDRAULICS
| Type | closed center |
| Capacity | 22.5gal / 85.2L |
| Valves | 2 to 4 |
| Pump flow | 18gpm / 68.1lpm |
| Total flow | 27gpm / 102.2lpm |
| Steering flow | 12gpm / 45.4lpm |
TRACTOR HITCH
| Rear Type | II |
| Control | draft sensing |
POWER TAKE-OFF (PTO)
| Rear PTO | independent |
| Rear RPM | 540/1000 |
| Engine RPM | 540@2100 / 1000@2100 |
INTERNATIONAL HARVESTER 3688 TIRES
The International Harvester 3688 is equipped with Ag tires, 11L-15 in the front and 18.4-34 in the rear, which provide good traction and stability for various agricultural tasks. The larger rear tires enhance flotation and reduce soil compaction, beneficial for field work on softer terrains. However, the tractor's weight distribution may challenge maneuverability in tight spaces, making it less favorable for smaller operations or specialized crops.
| Ag front | 11L-15 |
| Ag rear | 18.4-34 |
DIMENSIONS
| Wheelbase | 105inches / 266cm |
| Length | 184inches / 467cm |
| Width | 102inches / 259cm *Width at minimum tread |
| Height (cab) | 112inches / 284cm |
| Shipping weight | 11300lbs / 5125kg |
| Operating weight | 13200lbs / 5987kg |
| Ground clearance | 13inches / 33cm |
| Rear axle | 3.25 by 118inches / 82by 2997mm |
| Front tread | 60 to 84inches / 152to 213cm |
| Rear tread | 66 to 128.5inches / 167to 326cm |
DIMENSIONS & TIRES
The International Harvester 3688 features a wheelbase of 105 inches, providing stability for various field applications, but this may limit maneuverability in tighter spaces. Weighing between 11,300 to 13,200 pounds, it offers substantial traction on uneven terrain, yet it could pose challenges in transport efficiency. The front 11L-15 and rear 18.4-34 tire sizes indicate suitability for heavy-duty tasks, allowing for enhanced flotation and reduced soil compaction, making it ideal for agriculture.
| Wheelbase | 105inches / 266cm |
| Weight | 11300 to 13200 pounds |
| Front tire | 11L-15 |
| Rear tire | 18.4-34 |
3688 SERIAL NUMBERS
| Location | Serial number plate on the right side of the tractor frame, ahead of the rear axle |
| 1981 | 501 |
| 1982 | 1743 |
| 1983 | 2482 |
| 1984 | 2695 |
| 1985 | 3068 |
ELECTRICAL
| Ground | negative |
| Battery volts | 12 |