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How to adjust alternator belt on 1999 Lexus ES300?

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condo...@yahoo.com

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Feb 17, 2010, 7:01:34 PM2/17/10
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Dear Experts,


I have a 1999 ES300, V6. Very similar to the Camry V6.

I'm visiting Canada now (with the car), and it's really cold.

For those of you who don't know, rubber is contrarian;
rubber actually expands in the cold.

So, my timing belt has stretched. When I press
my finger beside the alternator, the belt has a lot
of movement and give. It needs to be tightened.
(Tires need to filled with more air too, and readjusted
in the spring.)

On the two Fords that I used to own, there were two
different ways to adjust the belt.

One had the old style, with a belt dedicated to the
alternator. To tighten the belt, you loosed an alternator
bolt, levered the alternator to make the tension high,
and then tightened the bolt down. Similar to this:
http://forums.motivemag.com/zerothread?id=3490925

Another Ford had a big serpentine belt. To make
more tension, you first loosened the lock bolt,
turned a screw assembly to push a pulley into the
serpentine belt, creating tension, and then
tightened the lock bolt.

Questions:

1)
on the 1999 Lexus es300, the belt for the alternator is
actually a serpentine belt, correct? Meaning, that it
connects multiple components.


2)
How do I create more tension on the 1999 Lexus alternator belt?
- move the alternator, or
- move a pulley into tension, or
- something else? what's the secret?


Thanks a lot!

jim beam

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Feb 17, 2010, 7:22:35 PM2/17/10
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On 02/17/2010 04:01 PM, condo...@yahoo.com wrote:
> Dear Experts,
>
>
> I have a 1999 ES300, V6. Very similar to the Camry V6.
>
> I'm visiting Canada now (with the car), and it's really cold.
>
> For those of you who don't know, rubber is contrarian;
> rubber actually expands in the cold.

incorrect on two counts:

1. rubber has a positive linear thermal expansion coefficient, not negative.

2. belts are not simply rubber - they have longitudinal aramid/glass
fiber reinforcing that dominates their linear properties.


>
> So, my timing belt has stretched.

1. the alternator belt is not a timing belt.

2. your belt has not stretched [see #2 above], it has simply worn. this
is common in cold climates where alternator loads are higher, especially
on startup. simply adjust or replace.


> When I press
> my finger beside the alternator, the belt has a lot
> of movement and give. It needs to be tightened.
> (Tires need to filled with more air too, and readjusted
> in the spring.)
>
> On the two Fords that I used to own, there were two
> different ways to adjust the belt.
>
> One had the old style, with a belt dedicated to the
> alternator. To tighten the belt, you loosed an alternator
> bolt, levered the alternator to make the tension high,
> and then tightened the bolt down. Similar to this:
> http://forums.motivemag.com/zerothread?id=3490925
>
> Another Ford had a big serpentine belt. To make
> more tension, you first loosened the lock bolt,
> turned a screw assembly to push a pulley into the
> serpentine belt, creating tension, and then
> tightened the lock bolt.
>
> Questions:
>
> 1)
> on the 1999 Lexus es300, the belt for the alternator is
> actually a serpentine belt, correct? Meaning, that it
> connects multiple components.

no, serpentine means it has a run with rollers on both sides of the
belt, not just one - it loops back on itself. multiple components can
still run on a non-serpentine belt.


>
>
> 2)
> How do I create more tension on the 1999 Lexus alternator belt?
> - move the alternator, or
> - move a pulley into tension, or
> - something else? what's the secret?
>
>
> Thanks a lot!


--
nomina rutrum rutrum

ransley

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Feb 17, 2010, 7:35:03 PM2/17/10
to

Replace if its near time, its worn. Its not the timing belt, but how
old are both, maybe both are overdue for new ones.

Tegger

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Feb 17, 2010, 7:45:12 PM2/17/10
to
condo...@yahoo.com wrote in news:0f597bb2-4c78-4978-b780-d000f887b0f4
@o3g2000yqb.googlegroups.com:

> Dear Experts,
>
>
> I have a 1999 ES300, V6. Very similar to the Camry V6.


Identical, actually.


>
> I'm visiting Canada now (with the car), and it's really cold.

That's Canada for ya. Too cold. Way colder than, say, DC just now...

>
> For those of you who don't know, rubber is contrarian;
> rubber actually expands in the cold.

It shrinks, like anything else.

It also gets /harder/ and s/slipperier/, which you're misinterpreting as
expanding.

>
> So, my timing belt has stretched.

T'ain't a timing belt. It's an accessory drive belt.

> When I press
> my finger beside the alternator, the belt has a lot
> of movement and give. It needs to be tightened.

<snip>

>
>
> 2)
> How do I create more tension on the 1999 Lexus alternator belt?
> - move the alternator, or
> - move a pulley into tension, or
> - something else? what's the secret?
>

The secret is: one bolt above the alternator and two underneath it. I
think they're all 14mm, but I'm not certain.

The one above (points to the SIDE) must first be loosened slightly.

The one below that points towards the SIDE of the car (same as the one
above) also needs to be loosened.

After that, you turn the one below that points to the FRONT of the car
until the alternator belt has the right amount of tension. Clockwise
will tighten.

Then you snug 'em all back up again. Piece of cake.


--
Tegger

Jeff Strickland

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Feb 17, 2010, 10:34:46 PM2/17/10
to

<condo...@yahoo.com> wrote in message
news:0f597bb2-4c78-4978...@o3g2000yqb.googlegroups.com...

> Dear Experts,
>
>
> I have a 1999 ES300, V6. Very similar to the Camry V6.
>
> I'm visiting Canada now (with the car), and it's really cold.
>
> For those of you who don't know, rubber is contrarian;
> rubber actually expands in the cold.
>
> So, my timing belt has stretched. When I press
> my finger beside the alternator, the belt has a lot
> of movement and give. It needs to be tightened.
> (Tires need to filled with more air too, and readjusted
> in the spring.)
>
> On the two Fords that I used to own, there were two
> different ways to adjust the belt.
>
> One had the old style, with a belt dedicated to the
> alternator. To tighten the belt, you loosed an alternator
> bolt, levered the alternator to make the tension high,
> and then tightened the bolt down. Similar to this:
> http://forums.motivemag.com/zerothread?id=3490925
>
> Another Ford had a big serpentine belt. To make
> more tension, you first loosened the lock bolt,
> turned a screw assembly to push a pulley into the
> serpentine belt, creating tension, and then
> tightened the lock bolt.
>

I don't know what Ford you had, but my Fords have a spring loaded tensioner
that never needs adjustment.

Me thinks your Toyota might be the same.


john

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Feb 17, 2010, 10:37:14 PM2/17/10
to
No, a serpentine belt transfers power from the crank pulley to all
accessory drives.

Yours is an alternator/AC belt. You also have a power steering belt.
This setup is an old jack screw (for Alt/AC) and slide rail (for PS)
adjuster design. It's cheap and clearly doesn't try to main proper
tension automatically as in those serpentine systems using automatic
tensioners.

So as described, you need to loosen the lock bolts and pivot bolts and
either turn a jack screw or use a pry bar against the PS pump to
adjust tension. Ideally, you'll need a Krikit-II gauge if not a more
versatile tension gauge. The Krikit-II is about $20 on Amazon.

john

unread,
Feb 17, 2010, 10:43:16 PM2/17/10
to
Must be a 1908 Model T. :D

No, Yota uses cheap jack screw and slide rail tensioners.

Cheney@whitehouse.gov Dick Cheney

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Feb 17, 2010, 11:29:49 PM2/17/10
to

<condo...@yahoo.com> wrote in message
news:0f597bb2-4c78-4978...@o3g2000yqb.googlegroups.com...


Short answer: You need a new belt and maybe the tensioner too.
You can't adjust anything to put more tension on your old belt,
it is stretched for sure and the spring in the tensioner has probably
relaxed some too. Just replace them.

--- news://freenews.netfront.net/ - complaints: ne...@netfront.net ---

FatterDumber& Happier Moe

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Feb 18, 2010, 4:50:38 AM2/18/10
to

You probably already googled this but here it is just in case you didn't,
http://us.lexusownersclub.com/forums/index.php?showtopic=55588

hls

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Feb 18, 2010, 9:15:28 PM2/18/10
to

"jim beam" <m...@privacy.net> wrote in message

>
> incorrect on two counts:
>
> 1. rubber has a positive linear thermal expansion coefficient, not
> negative.
>

I remember there were rubber band "engines" run by heat. And those "rubber"
bands did contract when heated. Now, I dont intend to go back and research
all this, but, IIRC, there is a whiff of truth in the basic statement.

Let's just say that there are rubbers (latices) and elastomeric compounds
which we
call rubber.

I am interested in the concept, but not enough to make an issue of it.

BUT, his concept is flawed. The problem is almost certainly a worn or
improperly
tensioned belt.


jim beam

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Feb 18, 2010, 9:39:51 PM2/18/10
to
On 02/18/2010 06:15 PM, hls wrote:
>
> "jim beam" <m...@privacy.net> wrote in message
>>
>> incorrect on two counts:
>>
>> 1. rubber has a positive linear thermal expansion coefficient, not
>> negative.
>>
>
> I remember there were rubber band "engines" run by heat. And those "rubber"
> bands did contract when heated. Now, I dont intend to go back and research
> all this, but, IIRC, there is a whiff of truth in the basic statement.

for some temperature ranges, yes indeed. but the belt our friend was
describing doesn't experience that, partially because it's not that kind
of "rubber", but mostly because of the reinforcing fibers.


>
> Let's just say that there are rubbers (latices) and elastomeric
> compounds which we
> call rubber.
>
> I am interested in the concept, but not enough to make an issue of it.
>
> BUT, his concept is flawed. The problem is almost certainly a worn or
> improperly
> tensioned belt.
>
>


--
nomina rutrum rutrum

condo...@yahoo.com

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Feb 19, 2010, 12:55:21 AM2/19/10
to
Right, it's not a timing belt. My bad. Good catch.

Thanks for the detailed instructions. I appreciate it!
I'll see if there are tools around to do it on my own.

Some misunderstandings about rubber and cold.

I'll make another post about what really cold
weather actually does to cars in the winter.


Moderator

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Apr 1, 2017, 6:18:02 PM4/1/17
to
replying to jim beam, Moderator wrote:
Beam,
why don't you just answer the poster's question. People like you are what
make forums so frustrating. Stay on topic or stay off the forum, "jack".

--
for full context, visit http://www.motorsforum.com/lexus/how-to-adjust-alternator-belt-on-1999-lexus-es300-9295-.htm


Sharx35

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Apr 1, 2017, 6:31:49 PM4/1/17
to
On 2017-04-01 4:18 PM, Moderator wrote:
> replying to jim beam, Moderator wrote:
> Beam,
> why don't you just answer the poster's question. People like you are
> what
> make forums so frustrating. Stay on topic or stay off the forum, "jack".
>
Who appointed YOU to be a fucking Moderator? FOAD.

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