I would definitely focus on the radiator. If you have some blocked or clogged tubes it can manifest itself as you describe.
Your IR thermometer will tell you right away if you catch it while it is close to overheating. Look especially close at the center of the radiator. Dan On Aug 17, 2012, at 12:35 PM, Peter Hertzing <phertz...@gmail.com> wrote: > Sorry Curt - coming into this late so I don't mean to be redundent. From > the sound of the description below - you have already done some work. My > first stop is always at the work I have done, making sure you have a fully > bled system with no air pockets. You already have the IR thermometer, so > the next think I would do would be to check the temp across the radiator, > looking for a cool spot. While unlikely, you could hae a colapsing > radiator hose restricting flow. > > Gould luck, I hate these gremlins. I currently have a randomly overheating > limo where the cooling fan doesn't turn on and it over heats - but by the > time you look at it the fan has come on and won't go off and works > perfectly. Definitly annoying. > > Peter > > > > > On Fri, Aug 17, 2012 at 11:21 AM, Curt Raymond <curtlud...@yahoo.com> wrote: > >> So yesterday morning things seemed good, temp stayed below 100C. >> Last night on the way home I got stuck in heavy traffic and the temp hung >> around 110C with trips up to the white line just before the red line. >> >> It was cool out, maybe 65F so outside temp is not much of a factor. >> >> One time it was getting high, I was running the cabin heat which was >> blowing hot air really well but making no difference and in desperation I >> slipped the trans into neutral and revved the engine which brought the temp >> down about 10C degrees really quickly. >> >> I didn't pull over and check the temp with my IR thermometer which I >> should have (looking weird on the side of the road be dammed) but my >> experience thus far shows that the relative position of the temp gauge is >> right, meaning as it rises the temp is really rising, although the gauge >> itself is usually off about 10C. So the car probably wasn't really >> overheating like I was afraid of but in the moment you get nervous... >> >> Anyway the revving thing makes me wonder if I haven't got a defective >> water pump. I can't see where its leaking and the coolant doesn't go down a >> noticeable amount. >> >> I suppose what I really need to do is replace the temp sensor but even a >> sensor not giving me the right temp is still giving me information that >> says the temp of the engine varies rather a lot (confirmed with the IR >> thermometer). >> >> Ideas? >> >> -Curt >> >> _______________________________________ >> http://www.okiebenz.com >> For new and used parts go to www.okiebenz.com >> To search list archives http://www.okiebenz.com/archive/ >> >> To Unsubscribe or change delivery options go to: >> http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com >> > _______________________________________ > http://www.okiebenz.com > For new and used parts go to www.okiebenz.com > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
