I'm doing a project for a Failure Analysis course and I have to come up with a failed sample to analyze.

I'm preferably looking for a part that failed when it shouldn't have. Analyzing a metal that was broken because its yield strength was exceeded is pretty lame.

Does anyone know of a part/component that fails regularly but shouldn't? I'm open to ideas here.

Originally posted by Submariner

Does anyone know of a part/component that fails regularly but shouldn't? I'm open to ideas here.


did my wife ask you to post that?


:eek:

Man, you must be at the postgraduate school. I took a few classes there

This is not a common failure but I had repeated distributor failures on a stock 2.25 motor that had everyone I know stumped for a while. The internals of the distributor were disintegrating. On one occasion it blew the cap and rotor off the top of the distributor and broke one of the advance weights and bent the plate that the points sit on. At the same time the engine had what sounded like excessive valve tap but everything measured out ok repeatedly.

Ended up, the problem was a loose gear on the front of the cam. As each lifter past the peak of the cam lobe at low rpms, the cam would snap forward causing the taping sound and apparently causing some pretty damaging side effects in the distributor.

I've got a 3.9 crank that snapped in two....seems as if a main cap came loose.

David

I am at the postgraduate school. How'd you only take a few classes there?

RR heater core?

-Jeff

tie-rods. i got 4 bent ones in 2 years.
trailing arms- made of LR rubber/ steel compound.
cruise control. nuff said.
ring gear & 10 spliners... yuk.

Interested in the heater core. How did it fail, at a weld/braze?

My turn signal stalk broke...I think you could be granted an honorary PhD if you could mount a convincing thesis linking the ghost of Lucas to this failure.

Oil cooler lines
Power sterring lines

How about a failed connecting rod from a 1949 marine racing engine.

Here is the "bad" one:

here is a good one:

I'm a civilian on the east coast at NAVAIR. We had a set up doing classes over a VTC. My job changed midstream and I couldn't spend enough time to do the program justice so I pulled out.

Do Diff covers count? I had a side gear shoot through the back of mine.

Diff covers don't count, sorry.

The window switch in one of my RRC's burnt its contacts when I was trying to roll it up with DeadLucas' head in the opening. Seems like he has compressed everything in his noggen and it has lost its flexibility.
I have a steering gearbox shaft at the rebuilder that was broken in two. Rock Rash?

JP

I'm still pissed you tried to file a claim with my insurance company over that damn window switch :mad: :mad: :mad:

This was an internal steering gear box shaft right? That might be interesting. I'm going to run some of these things by my prof next week. Thanks for all the replies, keep them coming.

stripped intermediate shaft on the borg/warner 1351 transfer case. seized viscous coupling unit from the same box.

Stock Land Rovers?

Boy am I bad!!!!!

Originally posted by Submariner
Interested in the heater core. How did it fail, at a weld/braze?

I havent actually looked to see where failed, but it is from a 1990 so it is part nylon impregnated plastic and part aluminum. I am looking at replacing it with an all metal core from my 1980 RR. As soon as i compare the two, its fair game.


Come to think of it I have a failed water pump that you can have.

-Jeff