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Bolt Torque Spec's

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Where you get them? I'm from the school that everything has a torque spec, but I've found very few in the FSM or Haynes. Just a random momentary rant!!!

I've found most of them when I rebuilt my '72 motor. Alot of them I found in the 'how to rebuild your nissan/datsun motor' book, some in the FSM, some in the Haynes...

What are you looking for exactly?

There is at least one wrong one in the "How to Rebuild" book..... the 30+fp that is listed for the cam towers is way off. Ask me how I found out.....

John, I'm sure I used that reference for my cam towers... what happened to yours? What torque should I use, and whats the best way to correct what I've done... loosen them a bit then tighten?

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Well, it's nice to see I'm in good company. I've been trying to find bolt torque specs for the thermostat housing/cap, as well as the rocker cover. However, after my melt down I found AutoZones repair guide. Seems to be fairly accurate from what I was able to cross reference. I going with 100 in/lbs for the thermostat housing/cap and 84 in/lbs for the rocker cover. Hope I'm somewhere in the ball park.

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John' date=' I'm sure I used that reference for my cam towers... what happened to yours? What torque should I use, and whats the best way to correct what I've done... loosen them a bit then tighten?[/quote']

"How to Rebuild..." listed torque at 33 ft-lb. One of my cam tower bolts snapped off with that, and I guess I am fortunate that it didn't strip the head. A search here in archives (and I think in the FSM) tells me that 15 ft-lbs would have been much more proper. I guess it would be best to back them off a bit, but I am no expert. I hope someone will chime in with some well founded educated suggestions for you. I have gotten suggestions from "simply back them off and re-torque to the proper setting" to "you've stretched the threads and now it needs re-threaded and new bolts". I ended up using another head and the one I messed up has found a spot in a corner.

John, thats an ugly scenario. Well I have both the FSM and the How to..., and Im certain I got most of the specs from the how to book but I guess I'll unwrap the motor, take the valve cover off, use the torque wrench at 15 and see if it doesnt click... Ill go up from there till I find what I actually did it at. Then I'll ease them off a bit and re-torque if needed. If I have stretched out the threads I think (although I'm no expert) that it would be better to torque a bit more than the 15lbs to 'compensate' if theyre stretched, but not go nearly as high as the 33lbs which may snap a bolt off.

It might stop snowing this weekend - I'll get on my parka and go in the garage and check!

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