OriginalSterm

Can anybody confirm the stock piston ring material? I have a set of rings (2 actually) from Goetze and I can't tell if the top ring is chrome plated or not. I did a search and saw that chrome should be avoided with an Alusil block.

What is the ring material, and what is the coating?

TIA

Zero10

I have a set of goetze rings beside me, and it does look like the top ring is chrome plated, but I am reasonably confident that goetze wouldn't do something that thoughtless.
Perhaps somebody knows for certain, since now I want to know as well, just for peace of mind.

Tom Carson

we need to find a way to reduce all the wrong information on these forums...maybe we need all footnoted references

the Mahle catalog states

top ring: "R 1.75 IF Cr P"
where...
R = Rectangular faced
in mm
IF = Internal bevel (top)
Cr P = Chrome plated Phosphate

2nd ring: "D 2 IF Cr P"
where...
D = (Dachfasen...or angled) Taper-faced,
in mm
IF = Internal bevel (top)
Cr P = Chrome plated Phosphate

bottom ring: "DSF 3 Cr"
where...
(Dachfasen Mit Schlauchfeder...or angled with spring)
in mm
Cr = Chrome plated

Kolbenschmidt reference states: Use of Cr-coated rings are "not possible" only with Nikasil, Galnikal or Chrome composite cylinders

and says Cr-coated rings are used with Alusil and Silumal composite cylinders

check out:

http://www.msi-motor-service.com/ks/en/main/index.asp

for lots of good info

(and maybe find that other post and reference this one)

OriginalSterm

Thanks Tom!