Alternator Noise

[btcman]

My 2001 Sport has 4.0L engine 100,530 miles and last week I had mechanic install Motorcraft spark plugs and wires to hopefully make it idle better when cold and warm - first since new. Mechanic said scanner showed MAF, IAC valve, etc. working within specs and thought new plugs and wire would help.
Still idles poorly. He checked vacuum hoses and no apparent problems. Probably need to do smoke test next- may be upper manifold gasket leak, but runs worse when warm than cool. Any other suggestions? I am planning on fixing truck up and selling, so trying to get it in good shape for sale.
Yesterday, I decided to clean the engine and covered the alternator with Saran wrap and sprayed engine good with Dawn/water mixture and washed engine off with light hose spray. I then blew water off engine with electric blower. I then cranked engine and unfortunately had forgotten to remove the Saran wrap and heard a loud whining sound and quickly removed the wrap about 5-10 seconds after starting engine. Then after engine ran for a few minutes, loud clicking sound started coming from alternator, as well as faint electrical smell. The clicking sound has not gone away after driving it around block. Have I fried the alternator either by still getting some water inside or with wrap covering it for maybe 10 seconds max? I should mention that I had let the truck sit for a week or so last week and on real cold day the battery was totally dead, but jumped it off and it has cranked with no problems since. Maybe the alternator was already going bad and had little or nothing to do with my cleaning engine. Sorry for long post, but wanted to give all of the gory details.

 

[geoph1986]

I don't think a little water would kill your alternator. maybe some of the saran wrap got sucked into it, or is attached to the pulley and is making the clicking. Long story as to how I know this, but melted saran wrap smells alot like burnt electronics.

 

[96eb96]

Remove the belt by tilting the tensioner with a 3/8" square ratchet, and spin the alternator by hand. Do this for the other pulleys as well. The saran wrap may have ended up around another pulley, I had this happen with a paper towel that blew up from the road. It made a terrible noise too. There may be a piece of saran wrap that got caught somewhere else.