Recently my 2013 buick verano stopped running. It would start but there wasn't enough power going to the battery. First thing I thought was the alternator. I opened the hood to find the serpentine belt had melted and the area is complelty covered in this black gunk. Can't really confirm what it is. Doesn't seem to be oil but it's everywhere. Anyone seen this before? Pics below.

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  • Welcome to Motor Vehicle Maintenance & Repair! I cannot see your image at work, but would bet you've shredded the serpentine belt. Check your different pulleys to see if any of them are bound up or frozen. If it's not the alternator, it could be any of the other ones (water pump, idler, tensioner, power steering pump, or A/C ... not going to be the crank shaft pulley which is bound up ;-) – Pᴀᴜʟsᴛᴇʀ2 May 29 '18 at 19:43
  • Remove the belt and find which pulley is frozen. – Moab May 29 '18 at 20:08

It looks like you have a long-term oil leak, perhaps from the timing cover or crankshaft seal.

This probably got on to the serpentine belt in sufficient quantities to cause slipping, overheating, and eventual failure.

If a serpentine belt fails due to wear or a bound tensioner, you will end up with dry black strands, powder, and chunks everywhere. However, the pictures provided make it seem like there is a lot of oil in the area as well.

Thourough cleaning, new belt, check the tensioner, and locate any oil leaks.

Best wishes.


Thanks everyone. It was the front crank shaft seal. It was leaking oil and the powder from the shredded serpentine belt made it the "gunk" substance.

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