International Harvester 686
The International Harvester 686 is a tractor produced by International Harvester. It is equipped with a 291 ci 4.8 L engine. The rated power output is 66.36 hp 49.5 kW. Transmission: Torque Amplifier. Operating weight: 7770 lbs 3524 kg.
Engine Power
66.36 hp
49.5 kW
Fuel & Capacities
31 gal
117.3 L
Transmission
Torque Amplifier
Operating Weight
7770 lbs
3524 kg
International Harvester 686 Serial Number & Year Decoder
Find the exact manufacture year of your tractor by checking your chassis serial number below.
Where to Find the Serial NumberThe serial number plate is commonly located on the front frame, tractor transmission housing (right side), or instrument panel badge.
Overview
![]() | 1976 - 1980 | 1976 - 1980 |
|---|
Production | |
|---|---|
Manufacturer | International Harvester |
Total built | 6,000 |
Original price was $14,700 in 1980 | |
The International Harvester 686 is nearly identical to the IH 666, it was simply renamed when the 86 series arrived in 1976. One major change did occur in 1979, when the 310 diesel replaced the 312. | |
International Harvester 686 Transmission | |
|---|---|
10-speed two-speed power shift | |
Transmission details ... |
International Harvester 686 Power | |
|---|---|
Drawbar (tested) | 58.01 hp
43.3 kW |
PTO (tested) | 66.36 hp
49.5 kW |
Performance test details ... | |
Mechanical | |
|---|---|
Two-wheel drive | |
Power steering | |
Disc brakes | |
Two-post fixed ROPS. |
Capacity | |
|---|---|
Fuel | 31 gal
117.3 L |
Hydraulic system | 16 gal
60.6 L |
Hydraulics | |
|---|---|
Type | open center |
Capacity | 16 gal
60.6 L |
Total flow | 12 gpm
45.4 lpm |
Tractor hitch | |
|---|---|
Rear Type | II |
Power Take-off (PTO) | |
|---|---|
Rear PTO | independent |
Rear PTO Type | 540 (1.375) |
Dimensions & Tires | |
|---|---|
Wheelbase | 103 inches
261 cm |
Weight | 7770 lbs
3524 kg |
Front tire | 7.50-16 |
Rear tire | 15.5-38 |
Full dimensions and tires ... | |
References | |
|---|---|
![]() | |
1979 Buyer's Guide published by International Harvester | |
Agricultural Equipment Reference Catalog published in 1980, by International Harvester |
Engine
Engine options | |
|---|---|
International Harvester 5.1L 6-cyl diesel | |
International Harvester 4.8L 6-cyl gasoline |
Engine Detail — 310 ci / 5.1 L Diesel
Manufacturer | International Harvester D310 |
Fuel Type | Diesel |
Configuration | 6-cylinder, liquid-cooled |
German (Nuess) built diesel that replaced the 312 diesel in 1979. | |
Displacement | 310 ci
5.1 L |
Bore/Stroke | 3.875x4.375 inches
98 x 111 mm |
Rated RPM | 2000 |
Starter volts | 12 |
Engine Detail — 312 ci / 5.1 L Diesel
Manufacturer | International Harvester D-312 |
Fuel Type | Diesel |
Configuration | 6-cylinder, liquid-cooled |
Displacement | 312 ci
5.1 L |
Bore/Stroke | 3.875x4.410 inches
98 x 112 mm |
Air cleaner | dry |
Rated RPM | 2000 |
Idle RPM | 900-2000 |
Oil capacity | 12 qts
11.4 L |
Coolant capacity | 21 qts
19.9 L |
Engine Detail — 291 ci / 4.8 L Gasoline
Manufacturer | International Harvester C291 |
Fuel Type | Gasoline |
Configuration | 6-cylinder, liquid-cooled |
Displacement | 291 ci
4.8 L |
Bore/Stroke | 3.75x4.39 inches
95 x 112 mm |
Rated RPM | 2000 |
Transmission
Transmission — Torque Amplifier
Transmission | Torque Amplifier |
Type | two-speed power shift |
Gears | 10 forward and 2 reverse |
Oil capacity | 64 qts
60.6 L |
With 15.5-38 rear tires. | |
![]() | |
Dimensions
International Harvester 686 Tires | |
|---|---|
Ag front | 7.50-16 |
Ag rear | 15.5-38 |
Dimensions | |
|---|---|
Wheelbase | 103 inches
261 cm |
Length | 162 inches*Overall length with 3-point hitch
411 cm |
Width | 89.4 inches*Minimum width
227 cm |
Height (exhaust) | 105 inches
266 cm |
Diesel Shipping weight | 7770 lbs
3524 kg |
Ballasted weight | 10340 lbs
4690 kg |
Front tread | 58 to 82 inches
147 to 208 cm |
Rear tread | 56 to 96 inches
142 to 243 cm |
Tests
Tractor Tests | |
|---|---|
NTTL 1151: 312 diesel Torque Amplifier 2WD | |
NTTL 1152: gasoline Torque Amplifier 2WD | |
NTTL 1336: 310 diesel Torque Amplifier 2WD |
Nebraska Tractor Test 1151 | |
|---|---|
312 diesel Torque Amplifier 2WD
November 3 - 14, 1973
Link: Nebraska Tractor Test 1151 file | |
PTO performance | |
Power at rated engine speed | 66.29 hp
49.4 kW |
Fuel use | 4.7 gal/hour
17.8 l/hour |
Drawbar performance | |
Max power | 58.01 hp
43.3 kW |
Fuel use | 4.6 gal/hour
17.4 l/hour |
Gear 3-Direct used for power test. | |
Max pull | 8,012 lbs
3634 kg |
Gear 2-TA used for pull test. | |
Nebraska Tractor Test 1152 | |
|---|---|
Gasoline Torque Amplifier 2WD
November 5 - December 3, 1973
Link: Nebraska Tractor Test 1152 file | |
PTO performance | |
Power at rated engine speed | 66.30 hp
49.4 kW |
Fuel use | 12.0 gal/hour
45.4 l/hour |
Drawbar performance | |
Max power | 57.29 hp
42.7 kW |
Fuel use | 5.7 gal/hour
21.6 l/hour |
Gear 3-Direct used for power test. | |
Max pull | 7,981 lbs
3620 kg |
Gear 2-TA used for pull test. | |
Nebraska Tractor Test 1336 | |
|---|---|
310 diesel Torque Amplifier 2WD
March 26 - April 16, 1980
Link: Nebraska Tractor Test 1336 file | |
PTO performance | |
Power at rated engine speed | 66.36 hp
49.5 kW |
Fuel use | 4.1 gal/hour
15.5 l/hour |
Drawbar performance | |
Max power | 57.71 hp
43.0 kW |
Fuel use | 4.1 gal/hour
15.5 l/hour |
Gear 3-Direct used for power test. | |
Max pull | 8,013 lbs
3634 kg |
Gear 1-Direct used for pull test. | |
Photos
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