1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

[whitejd12]

I'm re-installing a new head assy and not sure what torque and sequence to tighten bolts. Also, is there a torque for the 3 thermostat bolts? Thanks a lot!!

 

[boobie]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

96-120 in. lbs. for the head. Start in the center and work your way out in a spiral pattern. 60-80 in. lbs. for the thermo bolts.

 

[HighTrim]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

Like so.

 

[whitejd12]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

My torque wrench reads foot pounds. How does that convert?

 

[nwcove]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

divide inch lbs by 12

 

[whitejd12]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

So 8-10 ft lbs, right?

 

[HighTrim]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

yes

 

[whitejd12]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

What about the torque on the spark plugs?

 

[HighTrim]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

20 ft/lbs, never actually torqued a plug though. Snug em up, then about 1/4 turn more. Just by feel. Seen a few on here that stripped the threads using a torque wrench on them.

 

[whitejd12]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

Haha. Yeah that's why I had to replace the head. Oops. Thanks for your help. Got it all back together.

 

[boobie]

Re: 1972 18hp evinrude, Model# 18202R/ head bolt torque specs & sequence

1/4 turn is what I use also. An old aircraft mechanic told me that years ago.