emergency question

[donm]

Long story but I may have inadvertently loosened my crank shaft nut on the front of the engine. What should it be tightened too? I thought I saw somewhere 181 ft lbs but that seems very high. My torque wrench doesn't go that high.

Also, is this nut righty tighty or lefty loosey? And how can I keep the crankshaft from turning when I try to tighten it? Is sticking a piece of rope in one of the cylinders a good idea?

[18Fiatsandcounting]

The torque spec for the crankshaft nut on the 2L engines is pretty high, so 181 ft lbs could be right. I would verify with a shop manual. To loosen or tighten, most people use a 1.5" socket with a long breaker bar, or a pipe stuck over the end of your socket drive. Most torque wrenches go to 150 ft lbs, so I'd go to that level and then some. Don't make the mistake that I did many years ago of under-tightening this nut, as mine fell off while driving down the road. Surprisingly, the engine continued to run although it rapidly overheated because the water pump wasn't spinning. No alternator, either, but that was the least of my worries.

To keep the engine from turning, DO NOT stick a rope in the cylinder head. Usually the clutch will hold, so put the car in 4th gear, have someone press the brake pedal pretty firmly, and have a go with your breaker bar. Some people also make a locking device out of angle iron which then bolts in place of the flywheel inspection plate on the bellhousing and locks the flywheel.

An impact wrench will work although this requires removing the radiator to get access.

The nut is a right hand nut, i.e., counterclockwise to loosen and clockwise to tighten.

-Bryan

[wetminkey]

Per the Fiat Shop Manual, all engines, '75 - '82 proper torque is 181 ft lbs.
I don't measure (too hard) - I just use this setup, and tighten as best as I can (without breaking anything!):

It works.

[Nut124]

My opinion has been that the exact torque here is not as important as in the main and rod brg caps, or head bolts.

The manual provides a torque for just about all bolts, nuts. This one in based on the size of the thread.

I just use an impact wrench and do apply some medium locktite. Never cared to check the torque, but do know my impact wrench does provide 100+ ft-lbs.