Got back yesterday from another "Grapevine" road-test...and the results are indeed "very telling"! Bottomline is: my radiator needs an old fashion boil-out, rodding...or core replacement. The block and head water passages might need some "descaling" as well. It's my intention to stick with the copper/brass original style 4 core, which is why I'm going to a friend recommended shop, as they actually work with your radiator instead of the quick "scrap and replace with new junk" approach. I hear a lot of pros and cons regarding aluminum radiators...but I'm not sold on that idea (yet).
Temperature gauge results:
Photos one and two: my normal around town and freeway temps when fully warmed-up.
Photos three and four: my "new" normal freeway temp with just a slight grade.
Photos five and six: Going up the Grapevine!!! Truth is, right before I hit the summit, the gauge was kissing 250 (no photo), but over the summit on the down side, it did back off to the 230ish range!
Photo seven: The recovery tank was doing it's part on this drive, where it wasn't needed on the last one (without knowing the numbers). My fresh green coolant is now a rusty brown color, but I still didn't lose any coolant and the motor did not "act" as though it was over-heating...but I can tell things are going in the wrong direction!
I stopped at the bottom of the grade and had a "Dave's Double" at Wendy's...and sat for a while. When I finally started it back up, the radiator started guzzling up the coolant from the recovery tank...but no more than it expelled into it (as far as I can tell?). Nothing significant to report on the way home, but of course, my "new" normal freeway temp stayed in the 230 range. I stopped for a while at my best friend's house when I was about an hour from home...and got stuck in traffic (an accident) when I left, but things stayed pretty much the same at the slower speeds. Off the freeway and in beach city driving conditions, the "new" normal stayed around 220ish, so a stop at my friend's repair shop confirmed what I already suspected...dirt/rust/debris clogging the radiator is the prime suspect. A flushing will be the first step, but it's doubtful that this will be a cure...but when it's all sorted out, I will once again compare the readings between the Stewart Warner mechanical gauge and the factory gauge utilizing both of the electrical sending units (TS6S and American Autowire). Report will be coming...but don't hold your breath...it's going to take me a while!
Woody
