[TheForge] costs of ownership question

[Bruce .]

Sounds unlikely to me, but what do I know?  Try moving a toy magnetic
compass near the engine.  Any mass of steel or iron will deflect a
compass, but a magnetized one will deflect it differently than an
unmagnetized one.

With steel parts, you can demagnetize by lightly hammering on them;
but I'd be real careful about trying that on cast iron parts. However,
the "hammering" they get during use just suggests to me that this is
an unlikely idea in the first place.

On Tue, Sep 11, 2012 at 6:45 AM, terry l. ridder <terrylr at blauedonau.com> wrote:
<snip>
>
> the oddest suggestion that i have heard so far was from an old marine
> mechanic; that the auxilary diesel engines are located in a higher
> than normal magnetic field perhaps due to parts of the ship being
> magnetized over the years.
>
> the piston moving in the magnetic field is generating it's own magnetic
> field and currents. which is causing the piston rods to bow ever so
> slightly. this slight bow in the piston rods is causing the cast iron
> sleeves to wear out-of-round. the old marine mechanic suggested that i
> have the entire ship degaussed. needless to say that is not going to
> happen anytime soon. degaussing a ship is not cheap by any standard.
>
> the longer the piston rod the more the rod would have the ability to
> bow.
>
> this old marine mechanic suggested that if possible rotate the mounting
> of just one of the engines 90 degrees and see if the wear on the cast
> iron sleeve also rotates 90 degrees. he said that would point to
> external magnetic fields causing the excessive wear on the engines.
><snip>
-- 
Bruce
NJ