torque specs for 1997 75hp cylinder head

[leorupp]

I've searched this forum for toque specs for a 75hp Force 97 model, didn't see any concrete answers I have a Seloc manual and it's a little confusing. The manual says 70,75,90,120hp with serial #093699 and later 120in lbs. which seems really low to me for a head gasket..? it says up to serial # 093699 225in lbs. which to me sounds more like it. right below those #'s , 85 and 125hp (no serial # or year specified) 225in. lbs. my serial # is OE255798 which is above the number listed , I'm just not comfortable with the 120in.lbs because the 85hp is double that....any solid advise would be great Thanks in advance

 

[Jiggz]

The 75HP has the so called "Torque and Turn" method of torquing the head bolts.
1. Lightly oil the thread of each bolt and its underside
2. Torque all bolts in circular pattern to 120 in-lbs.
3. Then starting from the center in circular pattern, turn each bolt an additional 90 degree and you're done.

If you have a digital or dial type torque wrench, you can verify the final torque when you do the additional 90 degree. But then the final torque value will still not be as accurate due to the lube'd threads and underside.

 

[leorupp]

Thanks Jiggz, that just seems like a really light number...? 120in.lbs is only 12ft. lbs ..roughly...wonder what the reasoning is behind the lube threads....don't recall reading that in the seloc manual...it's kinda sketchy for the 96-98 75hp models...

 

[Jiggz]

With lubed threads, required torque decreases approximately 40% compared to non-lubed threads to achieve the same tension or "clamping force" on fasteners. But it also depends on what kind of lubricant is used. With SAE oil 30~40, torque reduction can be as high as 45 percent and as low as 30 percent with SAE 40. With graphite, it could be as high as 50 percent reduction in torque.

Bottom line, the 120 in-lbs torque is about 55 percent of 225 which I believe is correct as long as you at least use graphite or SAE 30 oil for lube on the threads. Remember the 120 in-lbs is not yet the final torque until you do the additional 90 degree on all bolts.

 

[leorupp]

Thanks.....

 

[jerryjerry05]

If all else fails 225in. # or 20# is what most Chrysler Force use.