Frontier719
New member
I just wanted to confirm--I read the writeup on yotatech, but my chiltons doesn't have the spec on it
is the deflection for the alternator belt 1/2"?
is the deflection for the alternator belt 1/2"?
Quick reference: How much deflection in alternator belt?
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Frontier719
New member
"tight" is relative--I've never replaced any belts before so I have no reference of what is tight. I wouldn't want to burn out the bearings on a new alternator
I was always taught that you should be able to twist the belt roughly 90 deg on it's longest stretch after the belt has been ran to work out the slack. The belt is normally flat grab it in the middle of its longest run and twist it vertically. __ > | if you can't get it to 90 deg it's too tight. If you can roll it "inside out" ( __ > | >__ ) it's too loose. Never had an issue doing it this way.
TheDurk
Elite Member
I think that's too loose, especially on a new belt. The official spec requires a tension gauge and is different for new versus old belts. I actually own one I saw on eBay, but it's virtually impossible to use it unless the engine is on a test stand. There just isn't room. I go by feel, but I can't really define it. But to the extent I can use the gauge, I'm not far off.
http://tacoma.site40.net/4Runner_96-02_Repair&Wiring/techinfo.toyota.com/ileaf/02toyrm/02toypdf/02rmsour/2002/024runne/ch5vzfe/chasy/ovi.pdf
I think the YotaTech thread has it about right:
http://www.yotatech.com/f2/how-change-drive-belts-3-4-l-5vz-fe-216234/#post51500136
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4eigner
New member
I believe you're right. 1/2", not 1" was what I read. It's been a while...
Drcoffee
Senior Member
You can check if the belt is slipping by touching the alternator pulley after you shut down the engine. If it hotter than hell, its slipping. If its just warm and you can grab it without burning your hand, its fine. You also dont want to be too taught and wear out the bearings.
SpidermanGeek
New member
Wait.. do you have to manually adjust/tighten the drive belts? I've only ever owned cars with self adjusting tensioners. I thought I would just need to stick a pry bar on the tensioner pulley to relieve tension and change the belt. That's what I've always done with my other vehicles.
Sorry, I haven't looked much into this, so I'm completely ignorant on this particular aspect of maintenance for the 5VZ-FE.
I'm asking because I recently bought all new drive belts and am planning on replacing them shortly.
Sorry, I haven't looked much into this, so I'm completely ignorant on this particular aspect of maintenance for the 5VZ-FE.
I'm asking because I recently bought all new drive belts and am planning on replacing them shortly.
badattitude
Member
All three of the drive belts are adjusted with a screw adjuster/tensioner
SpidermanGeek
New member
Yeah, I see that now. Just had a read through of the posted YotaTech link.
nevada
Senior Member
as convenient as that type of adjuster is, they make it VERY easy to over tighten a belt.
I think the info above is correct. going off memory, I think its 1/2" deflection for a 12" span. but the twist method would probably work well also.
TheDurk
Elite Member
One point to remember is that at some point these belts wear out. They very rarely break. But when they wear out, they start to slip and squeal, and NO AMOUNT of tension will get them to stop, even if you are so tight the bearings are grinding to pieces and the alt armature is starting to warp.
So if you can't get it to stop slipping, you may need a new belt and not more tension, especially if the belt is of unknown age. For reference, my factory belts started to slip coming up to 120k, which was just when I had planned to do my timing belt. (I am of the opinion that 90k on the TB is overkill. I just wait to 120k and then do EVERYTHING that touches the timing belt, except the crank sprocket, plus the aux belts and some other stuff. But that's me.)
So if you can't get it to stop slipping, you may need a new belt and not more tension, especially if the belt is of unknown age. For reference, my factory belts started to slip coming up to 120k, which was just when I had planned to do my timing belt. (I am of the opinion that 90k on the TB is overkill. I just wait to 120k and then do EVERYTHING that touches the timing belt, except the crank sprocket, plus the aux belts and some other stuff. But that's me.)
But not too tight.
LittleCaesar
New member
Tightest needs to be the PS, with about 3/8"deflection. ALT, 3/8"to 1/2". AC, 1/2".
19963.4lsr5
New member
Too tight and you will wreck the front Alt bearing. 1/2 seems like what I shoot for but in reality it should just be tight enough to not hear the belt squeal if you turn on the lights and heater on hi at same time.
nevada
Senior Member
years ago I put a new PS belt on my 85 22re. I thought I had the belt tension good. but as said before, that style adjuster makes it very easy to get them too tight.
I got a few blocks from the house, went to turn, and it got completely stiff. WTF. pulled over and checked, my new belt was laying across the engine, and everywhere else, shredded..
damnit too tight...
I got a few blocks from the house, went to turn, and it got completely stiff. WTF. pulled over and checked, my new belt was laying across the engine, and everywhere else, shredded..
damnit too tight...
pluton
Senior Member
The official specs involve using a gauge, which nobody does.
My approach is to make them as loose as possible, as long as they don't slip, flop, or visibly vibrate while the engine is running at speed.
It amounts to the same thing as saying it should deflect more than 1/2 inch, but less than an inch when moderately pushed on.
My approach is to make them as loose as possible, as long as they don't slip, flop, or visibly vibrate while the engine is running at speed.
It amounts to the same thing as saying it should deflect more than 1/2 inch, but less than an inch when moderately pushed on.
