Can anyone tell me what would cause a manifold to get so hot that it glows orange? I just bought the 1985 626 and seemed to run fine. I drove home about 20 miles on the freeway, and by the time i got home, i smelled something burning. It was the manifold just super red hot! i could see the 0-2 sensor and it to was glowing. The aluminum flex hose that surounds the pipe leading to the carb housing, was burned to almost ashes! The speedo cable was touching this as well and the plastic on it burned as well, locking the accelerator in place! i checked all fluids: antifreeze, oil, trans and everything was fine. The temerature gauge was at a middle range. So it didn't overheat, but i cant figure out why the manifold got that hot. Does anyone have an idea as to why the manifold would get this hot? I thought that it was going to blow up. HELP ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Please............................................ ......

 

i have no idea. the car is just old i guess.

 

Well the car has 127,000 original miles and runs very strong other than the red hot manifold! Someone suggested that maybe the carb was burning too rich, but i can't see that being the case either when it just passed emmisions with flying colors. Sheesh! I'm really at a loss here..................

 

Carb running too rich should cause the exact oposite. Too much fuel creates a poor combustion that would not only run up you emission level but also tend to cool the exhaust system down. A too lean condition is more likely. Give a very good check to any vacuum leaks that may have been compensated for at idle with the idle mixture screw. If your O2 sensor is not fried already, check the signal voltage at both idle and with rpm raised to 2500 or so. The O2 signal should fluctuate every second or so between approx 0 and 1 volt. 0 to 300mV is a lean condition and the closer you get to 0 the more lean it is. Same with 600mV to 1.0 volts. The closer to 1.0 volts the richer. Give that sensor a check if not cooked and see how the mixture is looking.
127k miles on an 85? where did you get it and do they have another!!

 

also don't use cheap gas. fill up 91 for few times and you'll feel the different after awhile. buy some engine cleaner and fuel tank cleaner...

just some suggestion to do more maintenance

why not try everything??

 

Try taking a look at your cat. conv. see if it is partially clogged.

JMBaggie