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Engine Mount (3/4" Stud) Dimensions

Determining Engine Mount Weight Capacity


Below are the formulas to use to determine the required pounds per engine mount.

Formulas

Front Engine Mount

(W x 0.4) x 0.5 = lbs per mount

Back Engine Mount

(W x 0.6) x 0.5 = lbs per mount

W = weight of engine and gearbox

Example:

Total weight of engine and gearbox = 1,200 lbs.

Front Engine Mount

(1,200 x 0.4) x 0.5 = 240 lbs per mount

Back Engine Mount

(1,200 x 0.6) x 0.5 = 360 lbs per mount


General Weight Distribution
R&D Marine Engine Mount weight distribution
  1. Find the center of gravity by balancing on a roller (If possible)
  2. If the center of gravity cannot be found, assume a weight distribution of 60% on the rear engine mounts, with 40% on the front engine mounts (if the rear engine mount is in line with the flywheel)

Technical Specifications


Part # Stud Size Capacity Per Mount Foot Print Mount Pre-Loaded Deflection Minimum Height Maximum Height
800-020 3/4 UNF 80-231 lbs 4" 0.09" 0.09"-0.21" 3.05" 5.38"
800-021 3/4 UNF 120-411 lbs 4" 0.09" 0.09"-0.21" 3.05" 5.38"
800-022 3/4 UNF 250-561 lbs 4" 0.09" 0.09"-0.21" 3.05" 5.38"
800-023 3/4 UNF 300-681 lbs 4" 0.09" 0.09"-0.21" 3.05" 5.38"
800-035 3/4 UNF 340-761 lbs 4" 0.09" 0.09"-0.19" 2.81" 6"
800-051 3/4 UNF 80-235 lbs 4" 0.09" 0.09"-0.21" 3.47" 5.45"
800-052 3/4 UNF 120-415 lbs 4" 0.09" 0.09"-0.21" 3.47" 5.45"
800-053 3/4 UNF 250-565 lbs 4" 0.09" 0.09"-0.21" 3.47" 5.45"
800-054 3/4 UNF 300-685 lbs 4" 0.09" 0.09"-0.21" 3.47" 5.45"
800-042 3/4 UNF 160-671 lbs 4"-5.5" 0.19" 0.19"-0.30" 3.39" 6"
800-028 3/4 UNF 80-233 lbs 5"-5.5" 0.09" 0.09"-0.21" 2.93" 6.5"
800-029 3/4 UNF 120-413 lbs 5"-5.5" 0.09" 0.09"-0.21" 2.93" 6.5"
800-030 3/4 UNF 250-563 lbs 5"-5.5" 0.09" 0.09"-0.21" 2.93" 6.5"
800-031 3/4 UNF 300-683 lbs 5"-5.5" 0.09" 0.09"-0.21" 2.93" 6.5"
800-063 3/4 UNF 500-1,300 lbs 5.5" 0.12" 0.12"-0.25" 3.97" 7.16"
800-064 3/4 UNF 650-1,700 lbs 5.5" 0.12" 0.12"-0.25" 3.97" 7.16"
800-065 3/4 UNF 1,100-2,101 lbs 5.5" 0.12" 0.12"-0.25" 3.97" 7.16"
800-015 3/4 UNF 500-1,200 lbs 5.5" 0.12" 0.12"-0.25" 4.04" 7.22"
800-016 3/4 UNF 650-1,500 lbs 5.5" 0.12" 0.12"-0.25" 4.04" 7.22"
800-017 3/4 UNF 880-2,00 lbs 5.5" 0.12" 0.12"-0.25" 4.04" 7.22"