Hi

Few hours ago, I was driving with AC on. Suddenly battery light came on and some noise started coming from engine bay. I parked the car. I saw both AC and Alternator belts snapped. PS belt was intact.
Now my question is what can cause both belts to snap?

 

Check by hand whether the alternator pulley, compressor pulley, or idler pulley is seized.

 

i have left my car to the mechanic. His thoughts were that crankshaft pulley needs to be replaced.

 

Not sure why you posted on the forum if you are letting your mechanic handle the problem. The crankshaft pulley would only be the problem if it were damaged. Is it?

You would be wise to check the items I mentioned.

 

i posted here because I was doubtful on the diagnostic of the mechanic. I will go and check the above mentioned.
what kind of damage on pulley can cause this?

 

Visibly broken or wobbling with engine running.

 

If you need a new crank pulley i feel like you would have way bigger issues. Even here in the rust belt i never see them fail. Would take some crazy impact on the crank to damage it that badly ide think.

As for why both would snap at once, my best guess is one broke from a worn pulley bearing and that broke the other. I suspect the ac idler those things always go bad.

 

I guess HT-tech section is done here....

 

I don't think so because I take opinion from here and tell the mechanic to follow it.

 

 

Why no mention of possible seized alternator, compressor or idler pulley?

How much were you charged for removal of what appears to be an undamaged crank pulley?

 

I had tested all pulleys by my own hands. They are all moving freely. Also please check the lock in the pics. Its badly damaged

 

Here is the real damage on the crank shaft end. Now I have to get this part welded and machined

 

Also I paid nothing to him as I towed my car to other mechanic who has expertise in doing machine work. Now please tell me should the pulley needed to be replaced or can be reused? Also does crank bolt be reused?

 

My engine is D15Z6 which came in Europe.
I have 2 questions:
Will any d series pulley is compatible on my engine?
And are all the crank bolts with different part number like in the pic below will work?
@tony_2018 @muellersfan

 

oh wow it almost sheared the key, that key (little metal tab) will 100% need replaced. The crank pulley looks fine to me its where it mates to the engine that im scared of. Hopefully after some welding it can still key that pulley in place. Bolt should be fine to reuse as long as the mechanic didnt mangle the head of it getting it out. Couldn't hurt to replace it tho either.

Did you test the idler pulley while spinning them? its kind of hidden from view. Spin all pulleys and listen for any grinding noises, try and wobble the pulleys side to side. Something isnt right somewhere to cause that much damage. From the way the key sheared it kind of looks like the crank pulley was working its way off?

 

Something had to have seized in order for the key to shear off the crank like that. This is assuming the correct key was used and not something pulled out of someone's treasure chest of honda parts.

 

I think I had spin the hidden idler pulley down there. But for confirmation I will try again.
Secondly, there is another theory for all this mess by some fellows here. Maybe the thread was not fully tightened when the engine was swapped in 2015. But till now it is driven only 25K kms. Here is a video I made 1 year ago and after that car is only driven almost 1K kms.
@tony_2018

 

That also I cannot guarantee off. Because here mechanics usually uses there treasure chests 😀

and they don't use torque wrench also