Quote:
Originally Posted by Adriel
Wow! Thank you all for the replies! 
I started right after a long hot drive of 15 miles, so why was a couple cylinders not firing? Or, are you saying that cylinder was about to fire? That makes more sense.
After I posted this, I found my reamer! Did a test on a squeaky one, and we were right: the reamer barely goes in!  Is that normal? |
Yes, this is normal.
It is the reason why MB calls for using a reamer every time the glow plugs are removed / installed.
Breaking up the accumulated carbon is important.
Carbon frequently forms a semi rigid sock around the electrode, this acts as an insulator potentially causing premature (overheat) failure of the glow plug.
At the very least; this semi rigid Carbon sock insulation makes cold starting more difficult.
On my personal vehicles, I actively look for justification to remove, test and ream, at least once per year.
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Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
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Dynamometer.
Heat exchanger durability.
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1983 300D
1984 190D
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2002 Honda Civic
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