A/C Pulley seperation

[jokoza57]

Take a look at the attached picture and give me your thoughts on why this would have occured.

Background:

Engine rebuilt last september. No noticeable flaws while putting on both pulley's, (crankshaft). All was fine until one day I had taken a 60 mile trip.
As I pulled into my destination I noticed a slight clicking sound coming from the engine compartment. I got out and lifted the hood and looked around but noticed nothing unusuall. As I got back on the road for my return, (I had driven about 35 miles), when all of the sudden I started to
hear a loud clicking and then a loud clanging like the engine was coming apart. I quickly pulled off to the shoulder and opened the hood and looked around to find this pulley had broken loose. This particular pulley runs the a/c, (which I was not running at the time). I checked the a/c compressor
to see if the clutch was free-wheeling and it was. In over fourty years of working on cars I have never seen one do this. I had hit nothing that might have come up under the car...so I ruled that out as a possibility. The tension on the belt was normal....there just seems to be no explanation for this to have happened. I purchased the car from a guy that had literally toasted the engine. Maybe the pulley had minute fractures in it that were undetectable at the time of assembly. The guy I had bought the car from had run the engine w/o oil, but never told me he had. Once I started the rebuild I took the oil pan off and it had that strong burnt odor and of course very little black oil. Has any one had one do this or heard of this happening? Your imput is appreciated......

By the way all the bolts still remain on the crank as well as the main crackshaft bolt. Replacement is to be done soon.....

Thanks,

jokoza57

[Pu241]

Never heard of the AC pully failing, but we have had similar issues with the water pump pulleys. One of which is documented below.

See bottom of page #1 and Page #2 of the link below:

http://www.fordfestiva.com/forums/showthread.php?t=9137&highlight=pulley

[AKZack]

Hey, everybody, first post here, been registered for a while, just lurking in the shadows sort of 'casing the joint' to see if I really would enjoy this fray. Seems like for most of the time at least, most of the members are civilized and those who aren't are at least good for a laugh. Humor is good. Jokoza57, I have seen a similar problem occur in my wife's little car, a Chevy Sprint years ago. What happened in it, was that the engine flex plate had flexed past its fatigue point and cracked and broke in a rough circle, slipping when the car was driven, squealing like a stuck pig; about two or three times louder than a slipping fan belt.

In your case, I would surmise that since the engine was run almost to seizure, that this pully had been overheated, softened some and actually flexed some, due to the pressure of the belt and fatigued and separated. Any other ideas?

So, you are curious about me, I guess. My wife and I live in south central Alaska in a little unincorporated town called Willow. (Doesn't every state in the union have a, 'Willow?') We are about 70 road miles north of Anchorage which we visit often since we are both mature, retired individuals and have doctor appointments from time to time. We live just off the Parks Highway about mile marker 70, behind the Post Office and we can see our local Alaska State Trooper's house from our driveway. (We have a nice, quiet, safe neighborhood and great neighbors.)

I try to maintain our 89 E-350 Ford RV which is a Fleetwood Jamboree; a 1995 Honda Civic that needs tranny attention; a 2004 Honda Element that needs a valve adjustment; my 2004 Ford Ranger XLT which needs an oil change; my 1988 and 1990two Festivas that need to be combined to make one good driver. And, oh, yeah, my 6X6Argo needs general service and adjustments done--just changed the starter and fuel pump, need to clean and adjust the drive chains. Just had a thought (as rare as that may sound) that with Argo wheels and huge tires at 3 psi, a Festiva would be hard to beat in the snow. One Festivas is black 1988, used to be yellow; the other a 1990, beautiful blue-green.

My wife worked as a nurse for years, and I am a retired Special Ed public school teacher and 'Zack of all trades.' We are here in God's beautiful creation on perpetual vacation. Come see us sometime.

[bravekozak]

deep draw

The deeper you draw, the weaker the steel is at the radius point.
You probably can't guess how many of these pulleys were thrown out at the factory where they were made, due to cracks.

You have to have a good progressive die set (drawing a little at a time) + patient toolmakers.

I am certain they never xrayed any of them.

They have to xray scan every aluminum wheel because it is considered a safety item.

[AlaskaFestivaGuy]

I once heard of a case in CA where the generator pulley on a bug fractured and flew off the engine in pieces. Unfortunately, one departing piece pierced the engine lid and continued on to hit a kid on the sidewalk in the head, killing him instantly. There's a lot of kinetic energy in a rotating mass.