Volvo RWD 700 Forum

INDEX FOR 1/2026(CURRENT) INDEX FOR 5/2007 700 INDEX

[<<]  [>>]


 VIEW    REPLY TO THIS MESSAGE    PRINT   SAVE 

Black oxide coating on T-stat? 700

87 745 B230FT, thermostat failed at 290,000 mi. Looking inside the head, clean aluminum, stainless parts of the T-stat- spotless but the brass body is black, it was brass colored when installed. I change anti-freeze every two years. 50/50 with distilled water.

Inside of the radiator is also black (metal / brass)

I have been using the current Prestone green which I understand may be OAT extended life stuff.

Apparently this is a chemical reaction, just wondering if it may be harmful or is it actually protecting the brass from corrosion?

Until yesterday it had not been overheated since I bought it in 1997!






THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD

New Black oxide coating on T-stat? [700]
posted by  Rolyak  on Wed May 10 08:56 CST 2006 >


<< < > >>



©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.