I am rebuilding a 4.2 for a customer and the book tells me betweem 85 and 91 lbs for the number 1 2 and 3 crankshaft main cap bolts, and the rear main, between 81 and 88 lbs. well one problem, they never torque and i know if i keep pulling on them they will brake, so i go get 8 new ones, they take 75lbs and break, does anyone know if maybe the book i have is telling me wrong info? can anyone help me out? thanks, and just incase anyone may wonder, i have 16 diffrent torque bars in the shop, it definitely isnt the torque wrench thats bad, thanks for any help. (1997 F150 is what this came out of)

 

well i looked it up in Alldata, and for the main bearing stud bolts it should be 81-88 ft. lbs of torque. For the main bearing brace nuts (whatever those are) should be 30 - 40 ft. lbs. of torque. Let me know if you have anymore questions and i will look it up for you. Hope this helps.

 

Alien, what did you find out? Anything?

Tom

 

OK first of all, appreciate the help chump, and i hope my experience helps everyone here, and Tom, to answer your question, I learnt alot, I dont know what ford was thinking, i bought 4, yes, 4 sets of bolts, 240$ worth of main cap bolts, and broke a whole lot of them, reason ebing, according to my book here, and chump, 6 of the 8 bolts claim to need 81 to 88lbs, well guys, that aint happening, at 70lbs some broke, and at 75lbs others broke, some wouldnt even take the 75 and they wouldnt torque at all until, snap, they were gone, eventually i them to 65, with clean wholes, no oil and used heaviest thread lock i had, i know they will work, but I just want everyone to learn from my experience, dont even attempt the 81 to 88lbs, because youll just end up snaping them and frustrating the hell out of yourself, if you guys have any otehr questions I could answer Id be glad to, appreciate the help once again, and good luck.

 

Thanks Alien. Glad you got it worked out.

Do you have a racing team or something, hence the "AlienMotorsports"?? Website too?

Tom

 

Yea, race stock cars, circle track and build them too, no website, considering one, but none as yet.

 

where did u buy the main cap studs? I cant find them anywhere

 

Had the same issue snapping bolts I called the ford dealership to get torque specs, the tech had informed me that the specs have been revised to 37 foot pounds of torque with an additional 115-125°turn. And the plate is 40 pounds of torque. Just thought I'd let everyone know for future reference. Thank you alien motorsports for your post otherwise I would have snapped more bolts.

 

This depends on what bolts are use.
The bolts with a shoulder are torque to yield
And need 37ft lbs then plus 115-125 degrees.
I learned by breaking bolts as well.