Northstar Engines and System Technical Discussion Discussion, 2006 Northstar 4.6 overheating in Cadillac Engine Technical Discussion; Couldn't get a cheaper fix than that. Glad to hear you got it straightened out.
Thanks for the update...
purge line is always one of my first things to mention that people check when they have an overheating northstar ... usually they go straight for the worst case scenario but it's good to try a few other things first before thinking the worst
Something is squirly about the 2006 Lucerne CXS Northstars. I own one and it's a total lemon. I'm not sure if they were using up old stock motors or what but they really seem to be crummy compared to the DTS, even though it's essentially the exact same setup.
Don't they use steel in certain areas of the plumbing? Idk about the 06, but my 98 has steel piping, and that nipple on mine is steel. The lower rad hose comes with a steel coil to keep it from collapsing under suction. Pump impeller on mine is steel also.
Different metals in different parts of different engines............. in mine, the W/P impeller is S/S, the thermostat retainer/spigot is cheap "steel", the heater outlet uses a cadmium plated steel quick-connect into a steel pipe, the purge line/nipple bolt is heat treated steel (it also retains an engine lift strap), there is copper, bronze, brass, steel, pot metal, aluminum, plastic, silicone, rubber, who-knows-what-else in contact with coolant - the whole lash-up is a mechanic's nightmare............ but the entire Rube Goldberg arrangement is a LOT more (mechanically) reliable than stuff from 50 years ago (don't get into electrics and electronics).
Here's Rube's (and my) opinion of the Northstar.................