(In a 2001 Mercury Sable sedan) This Ford Vulcan V6 is a 3.0 L with a pushr
od valvetrain arrangement. The common 6g alternator is in the center of mos
t of the vid; however, the sound isn't clearly coming from there. The noise
is loudest shortly after starting and then it subsides somewhat. It doesn'
t subside much.
I initially suspected the alternator, but I removed serpentine belt and han
d-turned the alternator to inspect it. It turned smoothly without noise. No
ne of the other pulleys seemed to be have bearing trouble either (although
I'm not clear how to test them exactly).
The recording is from a simple Samsung Galaxy Centura cellphone, so the aud
io low quality, but it does reveal the noise in question. (I'll try to edit
it to eliminate the video element to reduce size. I apologize for now for
the raw form.)
The car currently functions fine except for the noise, which is audible a l
ittle to me while driving.
I'm guessing the valves are in trouble, but I'm not sure, and I'm not sure
what exactly would be wrong with them. And it still could be the alternator
. Maybe (although it seems to turn silently unattached) the tension of the
belt on the bearing will cause it to misbehave. What's my next step in dia
gnosing this problem?
From my knowlege of the vulcan in that application and the very poor
sound recording I would say you have a bad belt tensioner or idler
pulley. VERY common problem, easy to fix and not too terribly
expensive. I've replaced the bearings themselves, but easier to just
get the kit with the bearing pre-installed in new pulley
I was under time pressure when I had the belt off, and I wasn't thinking ri
ght. I was thinking it was dangerous to start without the water pump turnin
g. That's wrong, of course. For a short period of time, an engine, particul
arly a cold one, can survive without coolant circulation.
Anyway, upon another careful inspection of the sheaves (pulleys), I could s
ee the end plate coming off the AC compressor. This turned out to be the so
urce of the noise. Upon researching the problem, I learned other Vulcan 3L
owners dealt with similar AC compressor problem by bypassing it with a shor
ter belt, and that's what I did.
I used a 82.5 inch 6 rib (825K6) replacement serpentine belt http://www.tau
an-c-bypass-belt-5.html#post1780362 . It rubs a bit, but it's tolerable.
I took some pics during the repair and later discovered Google Photos, *wit
hout my intervention*, had composed a slide show story. Considering I contr
ibuted no editing, it's a testament to the advance of Google's software. ht
(I had trouble getting the old belt off; most of the pics show that.)
On Saturday, July 12, 2014 1:15:44 PM UTC-5, Geoff Welsh wrote:
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