I'll say it once again. What a great list we have here. I've had
probably 15 replies already about my belt squealing issue, on and off
the list. I now know more about fan belts and how they work than I ever
thought I would ever want to know! Thanks to everyone!!
Here's a summary of ideas from the group, and what I found out this
morning while loosening and tightening both belts.
Ed Esslinger, who also has an A/C'd Tiger, points out again what I think
he had told me years previously, that for a start, the way my belts are
routed is not good, and that having the A/C compressor work just off the
water pump pulley puts too much torque on the belt, if I understand
correctly. Ultimately, I know I will need to figure a way to change the
routing and add an "idler" pulley or two, but that will have to wait a
while, at least until the radiator is out again. I'll have to somehow
bring the alternator (which sits about where the stock oil filter setup
used to be) forward about 3/4 of an inch to line up the the crank
pulley, and as we know there's not much room there already. I don't know
if that's feasible to do yet. Is there any such thing as a double pulley
for an alternator?
Several of you suggested I look at the belts to see if they are glazed,
or shiny on the side and, if so, this could cause slipping and squealing
under a load.. I just compared them to a couple of new belts I bought
and the sides of the old belts do look somewhat shinier than the new
belts. I'm going to install the new belts tonight, just to see what happens.
I also notice that the brand new fan belts toward their bottom (that
faces the pulley grooves) have a different material of some sort. The
sides of the belts there have what looks like a cloth "stitching" on
them. It looks like this may be designed to help grip on the sides of
the pulley grooves. My old belts on the car now do not have this, even
though they're exactly the same brand. It looks like that stitching has
been worn off, maybe from slipping on the side of the pulley grooves. If
that's the case, I'm hoping new belts will help.
A couple of other suggestions were to check to see if the "v" belts sit
all the way in the pulley grooves. This seems like it may also be an
issue. The belt fits deeply into the A/C compressor pulley, but I notice
that the water pump pulley has deeper grooves in it, and the fan belt
does not seem to press all the way into the groove. KIs there a brand of
"V" belts that actually are shaped like a V? My current belts have a
flat edge to them facing the bottom of the pulley grooves.
The consensus of the comments so far is that my water pump itself is
probably OK. That will be a relief if that ends up to be the case. I
think (I hope???) this is true and it makes sense. At higher RPMs
(3-4000) "goosing" the gas pedal with the A/C on doesn't cause the
squeal (or rarely does). I would think if the pump is going bad I would
get the squeal at high RPMSs too, or maybe all the time. Also, when the
engine is cold and I turn on the A/C, I often get the squeal, even at
idle. Once the engine is warm (and the belts maybe a bit more flexible
from the heat?) that one annoyance doesn't happen, until I nail the pedal.
I'll report back to the list after I get the new belts on, in a lot more
concise manner. I just wanted to adress all the excellent comments you
have sent back from my question.
Thanks again!!
Steve Sage
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