Head torque and sequence.

[Tinman]

I have mainly 5.5- 30 hp omc motors from the 50’s. Is there a chart that shows the sequence and inch pounds of torque required for the different horse powers? Thanks!

[bobw]

These should be what you need.

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."

• This reply was modified 4 years, 8 months ago by Mumbles.

[Mumbles]

Here ya go. When torquing the cylinder head, start in the middle and work your way out in a circle so the head gets tightened down evenly. I usually start with 50% of the given value the first time around and increase it to 75% the second time and 100% the third time around. Tightening it down in stages will help prevent warping the head.

Note: This chart shows 5-7 and 8-10 Ft Lbs for the smaller motors. A torque wrench calibrated in inch pounds should be used for these motors as it will give greater accuracy. So that would be 60-84 and 96-120 Inch Lbs.

[Tinman]

Thank you bobw and mumbles, answered my question perfectly! Always appreciate the help!

[Tinman]

When reusing head bolts should I go with the lower value in inch pounds? Thanks.

[Mumbles]

I just torque them to the middle somewhere of the given values and it seems to work fine. As long as the threads are clean and lubricated, torquing to the lower end will give similar clamping results if the threads are dry and torqued to the higher end of the given values.

[Tinman]

Thanks once again!

[Author]

Posts