| Starting Serial Number: | Six (Model 55)... 5120001 - 5133400 |
| Dictator Eight (Model 62)... 9015001 - up | |
| Commander Eight (Model 71)... 8036001 - 8040000 | |
| President Eight (Model 91)... 6025001 - 6027400 |
Location: On frame under left front fender.
Jump to:
General Specs | General Engine Specs | Engine Tune Up Specs | Engine Clearances | Lube Chart
General Specifications:
| Model | Wheelbase (In.) | Shipping Weight (lb.) | Tire Size (In.) |
| 55 | 117 | n/a | 5.50-18 |
| 62 | 117 | n/a | 5.50-18 |
| 71 | 125 | n/a | 6.00-18 |
| 91 | 135 | n/a | 6.50-18 |
General Engine Specifications:
| Model | # of Cyl - Bore & Stroke | Displacement | Compression | Max Brake H.P. | H.P. per Cubic In. | # of Main Bearings |
| 55 | 6 - 3 1/4 x 4 5/8 | 230.0 | 5.00 | 80@3200 | .348 | 4 |
| 62 | 8 - 3 1/16 x 3 3/4 | 221.0 | 5.00 | 81@3200 | .366 | 9 |
| 71 | 8 - 3 1/16 x 4 1/4 | 250.4 | 5.15 | 101@3200 | .403 | 9 |
| 91 | 6 - 3 1/2 x 4 3/8 | 337.0 | 5.10 | 122@3200 | .363 | 9 |
Engine Tune-Up Specifications:
| Model | Plug Type | Plug Gap | Point Gap | Dwell | Ign. Timing | Ign. Timing Mark | Compression | Inlet Tappet | Exhaust Tappet |
| 55 | Champ - 2 | .025 | .018-.024 | 36 | M-15 A-23 |
Note1 | 100@1200 | .004C | .007C |
| 62, 71 | Champ - 2 | .025 | .018-.024 | 34 | M-25 A-27 |
Note2 | 105@1200 | .003C | .007C |
| 91 | Champ - 2 | .025 | .018-.024 | 34 | M-25 A-21 |
Note3 | n/a | .004C | .007C |
Note1: With spark control button pushed in for full advance, breaker points open when the punch mark 1/2" ahead of the DC1-6 (or UDC1-6) mark aligns with the peep hole pointer.
Note2: With spark control fully advanced, stationary breaker points open when the punch mark 3/4" ahead of the UDC1-8 mark on the flywheel aligns with the peep hole pointer.
Note3: With spark control fully advanced, stationary breaker points open when the punch mark 1" ahead of the UDC1-8 mark on the flywheel aligns with the peep hole pointer.
topEngine Clearances:
| Model | Piston Top | Piston Bottom | Ring Gap Oil | Ring Gap Comp. | Wristpin | Rod Clearance | Rod Endplay | Thrust on # | Main Endplay | Main Clearance |
| 55 | .012 | .002 | .013 | .013 | .0001 | .0008 | .005 | 3 | .003 | .005 |
| 62 | .012 | .002 | .013 | .013 | .0003 | .0008 | .005 | 1 | .003 | .001 |
| 71 | .013 | .0015 | .013 | .013 | .0001 | .0008 | .005 | 1 | .003 | .001 |
| 91 | .022 | .0015 | .013 | .013 | .0001 | .0008 | .003 | 1 | .003 | .001 |
Lubrication Chart:
| Engine | Transmission | Rear Axle | ||||||||||
| Model | Temp | SAE # | Temp | SAE # | Temp | SAE # | Rear Wheel Bearings | Front Wheel Bearings | Steering Gear | Clutch Release Bearing | Water Pump & Fan | |
| 55, 62 | Above 90 | 40 | Summer | 110FW | Summer | 110 | Pack w/Cup Grease | Pack w/Cup Grease | Chassis Lube | 160 Oil | Cup Grease & 30 Oil | |
| 45 - 90 | 30 | Winter | 90FW | Winter | 90 | |||||||
| 10 - 45 | 20 | Below 15 | 80FW | |||||||||
| Below 10 | 10 | |||||||||||
| 71 | Above 90 | 40 | Summer | 110FW | Summer | 110 | Pack w/Cup Grease | Pack w/Cup Grease | Chassis Lube | 160 Oil | Fan: 30 Oil | |
| 45 - 90 | 30 | Winter | 90FW | Winter | 90 | |||||||
| 10 - 45 | 20 | Below 15 | 80FW | |||||||||
| Below 10 | 10 | |||||||||||
| 91 | Above 90 | 40 | Above 35 | 110FW | Summer | 110 | Pack w/Cup Grease | Pack w/Cup Grease | Chassis Lube | 160 Oil | Fan: 30 Oil | |
| 45 - 90 | 30 | 15 to 35 | 90FW | Winter | 90 | |||||||
| 10 - 45 | 20 | -15 to 15 | 80FW | |||||||||
| Below 10 | 10 | |||||||||||
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