Cavitation is a serious problem only in direct injection diesels with 
thin cylinder  walls (think the large displacement Powerstrokes, not 
the original smaller displacement ones). The problem is that the 
cylinder flexes in and out with the pressure pulses of injection, 
causing a vapor bubble to occur in contact with the coolant side as the 
wall "pops" in and out.  When the bubble of water vapor collapses, the 
impact of the water from the liquid side erodes the cast iron of the 
cylinder wall (or liner).   Often shows up as a row of neat, exactly 
the same diameter holes down the liner or cast in place cylinder.  Some 
people are convinced this is electrolysis, by the way, which it is NOT.

MB has always used generous amounts of material in their block 
castings, and has never had a problem with cavitation.  I don't 
remember any instances of coolant passages cracking in use to the 
outside as has become common in Cummins six cylinder truck diesels 
lately, either -- again, the problem is insufficient material, flexing 
due to running vibration causes the very thin cast iron to fatigue and 
crack (also known as stress corrosion these days).

The 60X heads were re-designed a couple times, and most of them, even 
the -14- heads, work fine.  The -14- heads WILL crack if overheated, 
pretty much without exception.  The oil passage problem has been cured 
with a re-enforced head gasket, now containing a metalized section 
across the oil passage.

All of them can warp or collapse if seriously overheated though.

Peter


_______________________________________
http://www.okiebenz.com
For new parts see official list sponsor: http://www.buymbparts.com/
For used parts email [EMAIL PROTECTED]

To Unsubscribe or change delivery options go to:
http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com

Reply via email to