Lycoming crankshafts

"Morgans" wrote in message
...

"Capt. Geoffrey Thorpe" The Sea Hawk at wow way d0t com wrote

Same problem in the auto industry. The bigges difference is that broken
cranks or cams or... show up in the warrenty data - not in NTSB accident
reports.

Can you point to a major auto maker's crankshaft recall?
--
Jim in NC

Manufacturer Number Product Reason Country Year

General Motors 150000 Chevrolet, Chevette, PontiacT-1000 Defective
crankshaft U.S.A 0/1986

Mazda 25400 Familia, Laser Danger of crankshaft fracture and engine
damage due to defective bolts WORLD WIDE 7/1990


Suzuki Motor Corporation has determined that the Eiger automatic ATVs were
produced with an internal manufacturing flaw. This flaw could cause the
crankshaft to break during operation. A broken crankshaft will interrupt
power transfer from the engine to the transmission and the drive wheels,
leaving the driver stranded away from his or her base of operation.


My dad had a mid 70's Plymouth that broke 2 cranks in about as many years -
last time he ever bought a Chrysler product. Don't know if there was ever a
recall, or it was just covered under the warrenty.

Plus, if you break, say 0.01% of the crankshafts (1 out of 10,000), would
that trigger a recall for a car? How about for an aircraft? I think the
"threshold" is a lot different.
As suggested by the following:

........ begin quote......
A 'walking' crankshaft is a crankshaft that moves too much inside the
engine. This is also known as excessive thrust bearing play. The movement is
usually due to the crankshaft not fitting inside its bearings correctly.
While not bad for the crankshaft, the movement can place excessive or uneven
loads on the bearings, causing premature failures.

Many 2G owners have suffered from walking crankshafts. It appears that
Mitsubishi built many 2G engines using defective crankshafts, which were
machined out of specification and are thus capable of moving around too much
inside the block. All 2G model years appear to be affected to some degree.

snip

It can be difficult to tell if a particular car is experiencing crankwalk.
Symptoms are usually indirect and difficult to diagnose until major damage
occurs.

snip

Although 2G DSM owners have been anxiously awaiting a recall or TSB on the
crankwalk problem, there is none as yet. According to Paul's second post on
the subject, there may never be a TSB, although some members of DSM Canada
are pushing for one in this thread on their discussion board. As a result,
it is doubly important that affected 2G owners get their bearings (or
blocks, if necessary) replaced before their warranty expires. This might be
difficult for owners of aftermarket clutches, as dealerships often claim the
aftermarket pressure plates are the cause of the problem.

......... end quote ......
--
Geoff
The Sea Hawk at Wow Way d0t Com
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