A friend helped me replace my head gasket in December. We also put a new water pump and timing belt on at the same time. The car ran like a top afterward and I drove it for 1200 miles before I heard a roar from under the hood one morning when I accelerated. When I released the gas, the roar slowly went away. I was just starting to pull over when I lost power steering and my battery light came on. When I got pulled over I popped the hood and saw that the crank pulley had come loose. The bolt had snapped off.

We towed the car to my friend's house and went to a junk yard and got another pulley, woodruff key and bolt. We were able to drill out what remained of the bolt and we then started reassembly. This time my friend put loc-tite on the bolt to be sure that it wouldn't back out. I drove the car 300 miles before I heard the familiar noise.

I cut the car off before the pulley came off. We started removing the bolt and damned if the thing didn't break off on us. We had a hell of a time getting the rest of the loc-tited bolt out, but finally we did.

We noticed that the woodruff key slot in the crank is worn a bit, but the pulley seems to be fine. We've gotten a new bolt and woodruff key and are ready to start reassembly again.

I'd like to see if any of you have experienced the same or similar problem and how you fixed it. I found the loc-tite fix and am considering it as a possibility. A local mechanic (who pulled over to offer his help the first time this happened) said that he had seen this before and that sometimes the pulley would have to be spot welded to the crank.

Anybody else have anything to offer as a possible fix?

I can't help but suspect that perhaps my friend is over tightening the belts for the AC compressor, alternator and power steering pump. Would over tightening these put enough strain on the crank pulley to snap the bolt? What is the proper tension for these belts (he says to tighten them until you can twist them a quarter turn).

Thanks in advance for your insight.

 

dude, did you torque that thing back on? from the sound of everything your saying doesnt sound like you dont even own a torque wrench, Or a Helms manual...

 

Twinring,

The bolt was torqued to spec both times. And yes I own both a torque wrench and a Helms manual and have made use of both.

 

install the bolt with an impact!

 

well, sorry for the mal assumption, I know for a fact that honda techs replace the bolt whenever its removed. its an $8 piece. there might be some damage from the first time it came off.

 

I can confirm that they do not. A little trick mechanics do. Anytime your oil is changed, tranny fluid is changed, etc your charged for a replacement drain bolt, just like your charged for a crank pulley bolt. This subracts the part from inventory in the computer system. At the end of the month, inventory is counted by hand, any surplus is added up $ wise, and divided among the techs as a bonus. If it takes 2.5 quarts to change your tranny fluid your charged for 3. They don't throw away the other half a quart.


Anyway I can't beleive the bolt snapped I must of put 300lbs of pressure on one before to get it off, and it didn't snap.

 

Egad. Well, I'm definitely replacing mine when I check for oil leaks very soon. Sounds quite scary actually.

 

We don't change that bolt, there's no need.

Whatever you're talking about splitting up surplus money doesn't happen at dealerships. That's something Bubba's Repair Shop would do.

If the groove for the woodruff key is damaged, you're going to keep having problems until you replace the crank or find some way to fix the original.

 

Any idea how much a typical crank replacement will run me?

 

More then the engine is worth if you're paying someone to do it.