about a month ago the crankshaft bolt came loose and the pulley came off the shaft. i put everything back together and its been fine till today. i put it all back together again and by the time i got it back home (1 1/2 miles) it came loose again. what could be making the bolt come loose? any ideas please!
thanks, mike

 

I've never heard of this problem. Most have problem loosening the crankshaft pulley retaining bolt.

How are you torquing the bolt to rated torque spec?

BTW, if the crankshaft timing belt drive sprocket becomes disengaged from the woodruff key (it could fall out if pulley is loose), the crankshaft and camshaft can slip timing and valves will be damaged, and perhaps valves damage pistons.

good luck

 

i'm using a torque wrench and torquing to honda specs.

the woodruff key stays in place all the time, don't know how or why but it does. the bolt doesn't come out all the way but just enough for the pulley to come off. now i have to get a new pulley this time because of it wobbling around between the bolt and the shaft before i could shut it down.
it doesn't look like it messed up the shaft or woodruff key just the pulley.

i guess i'm gonna try using thread locker on the bolt. if you have any other ideas please let me know.

thanks

 

Describe your torque wrench 3/8" or 1/2" drive and rated for what torque.

Is it possible you are tightening to 180 in-lbs instead of 180 ft-lbs?

Any possibility the threads on bolt or crankshaft are damaged? It should tighten by fingers in/out easily.

Finally, I would retighten and use some thread lock.

good luck

 

Did you remove the pulley before the pulley came off ? Usually it won't just come off, i took mine off when i changed the timing belt with an 700ft/lb gun and it didn't even budge until i used some propane heat on it. When you install the pulley back on, use some loctite on it.

 

do you have the pulley hold down tool . I don't think you can get 180 lbs of torque with out a good way of stopping the engine from turning .

 

that is strange usually with the ccw rotation will cause the nut to tighten . I broke one free at my job and tightened it till the engine started to turn when I got it home about 25 miles my 1/2 inch IR worked a little to get it off again. the new pulley might solve your problem

 

Are you sure your torque wrench is working? Serious question, 180ft lbs is all your weight pressed on the end of a standard 1/2 ratchet. I used a breaker bar inside of a 5 ft pipe clamp and pretty much put all my weight 175lbs at about 3 ft out on the bar.

You shouldnt need thread locker if its coming lose something is wrong.