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View Full Version : OT : The 523i was a dud ! ? Nikasil



Zeuk in Oz
08-23-2005, 05:44 PM
Half compression on 1 cylinder, corrosion in floor pan seams, leaks from every possible place......... the mechanic didn't bother to do the leakdown test given what a mess it was.


I am still having trouble understanding if what my mechanic is describing is wrong with Nikasil engines in Oz is the Nikasil problem or something else.

"Honing marks in the cylinder wall are meant to retain oil which lubricates the piston.
In Nikasil lined blocks the honing marks are removed by the piston rings and the cylinder walls become too smooth and cannot retain the oil required for lubrication so the piston is running virtually dry.
This then leads to excessive wear of the rings and loss of compression which replacement of rings will not fix for very long as the new rings also wear out very quickly. "

Does this sound like a sulphur issue or something else.
Any learned opinions ?

By the way - discovered that they stopped putting Nikasil cylinder liners into our sixes in March 1998 (Thanks Shogun) so will look for a steel lined engine next time.

Zeuk in Oz
08-25-2005, 12:42 AM
Bill R, Shogun, Whit...... Anyone ?

uscharalph
08-25-2005, 01:15 AM
Half compression on 1 cylinder, corrosion in floor pan seams, leaks from every possible place......... the mechanic didn't bother to do the leakdown test given what a mess it was.


I am still having trouble understanding if what my mechanic is describing is wrong with Nikasil engines in Oz is the Nikasil problem or something else.

"Honing marks in the cylinder wall are meant to retain oil which lubricates the piston.
In Nikasil lined blocks the honing marks are removed by the piston rings and the cylinder walls become too smooth and cannot retain the oil required for lubrication so the piston is running virtually dry.
This then leads to excessive wear of the rings and loss of compression which replacement of rings will not fix for very long as the new rings also wear out very quickly. "

Does this sound like a sulphur issue or something else.
Any learned opinions ?

By the way - discovered that they stopped putting Nikasil cylinder liners into our sixes in March 1998 (Thanks Shogun) so will look for a steel lined engine next time.
I'm having a hard time determining what you're asking. What is your mechanic recommending?

632 Regal
08-25-2005, 11:48 AM
I think what your mechanic is refering to is a worn cylinder or something.

Nikasil is wear that occurs at the tops of the cylinders due to the nikasil plating coming off, nothing to do with honing marks and the such.

Zeuk in Oz
08-25-2005, 04:56 PM
I think what your mechanic is refering to is a worn cylinder or something.

Nikasil is wear that occurs at the tops of the cylinders due to the nikasil plating coming off, nothing to do with honing marks and the such.

Thanks, that is what I thought too, just wanted someone else to say it.