1FZ alternator belt on wrong side of pulley (1 Viewer)

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Sep 19, 2018
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Location
New York
Hello,

I recently had my belts changed in a pinch and noticed the shop (that I will not be going back to) ran the belts on the wrong side of the idler pulley below the alternator. Based on all the diagrams I have seen, the belt should go outside the pulley and not inside.

Can I just re-run the belts the proper way or should I buy new belts since I’m worried they might be stretched now?

How it looks right now (wrong):
0B847B13-FD3E-4C7A-B543-F718D780B86C.jpeg


how it’s supposed to look:
BCF2400F-6A01-4659-AB43-ED02B88B8799.jpeg
 
I think you'll be fine. Your belts stretch regardless of if they are routed correctly or not. As long as they have not been damaged, and are the correct belts, (they seem like they'd have to be longer to fit on the other side? I haven't tried what they did to see if there's enough belt to reach around that pulley) I believe you'll be ok. If it was mine I'd reroute it without a second thought.
 
I think you'll be fine. Your belts stretch regardless of if they are routed correctly or not. As long as they have not been damaged, and are the correct belts, (they seem like they'd have to be longer to fit on the other side? I haven't tried what they did to see if there's enough belt to reach around that pulley) I believe you'll be ok. If it was mine I'd reroute it without a second thought.

Thanks! I will buy a spare set of belts just to have them but will just reroute these for now. They do not appear to be damaged or worn in any way and they only have a few hundred miles on them in this configuration.

They are definitely the right belts, I got them from my favorite online store, Wits End and Joey always stocks the right parts. I’m guessing the shop used some extra force to get them on the wrong way.

I heard some new noise that tipped me off to something being not quite right. I thought it might have been one of the idler pulleys making the noise but when I took a look I noticed the weird routing.
 
They may or may not be damaged, it depends on the monkey that changed them out. It could NOT have been easy to install them like that. The other pain is that now you have to run your adjuster bolt all the way back out, since they had to go all the way in to get it on.
 
Lots of us have removed/disposed of the idler pulley. It really seems to serve no EFFECTIVE purpose. It does not reduce belt vibration noise enough to notice. Not big deal. We have pulled a bunch of these and the owners notice NO difference. We just plug the hole with a dummy bolt. Does not seem to affect belt life or noise. Mine has been off for about 8 years.
 
I'm not even sure how they did that. It seems like I can barely get my belts back on the correct side

Haha.. I wish I knew but all I know is that I need to fix this right away I believe it is causing me some alternator issues.
At the very least, I believe it is causing some noises... and I hate noises.
 
Haha.. I wish I knew but all I know is that I need to fix this right away I believe it is causing me some alternator issues.
At the very least, I believe it is causing some noises... and I hate noises.

It is almost without doubt that running stock/oem length belts (that route)....will cause undue pressure on your alternator bearing.

Another thing you will see sometimes are cogged belts.

Belt Route.jpg


belt routing.png


Belts Wrong.jpg
 
I'd replace the belts because the only easy way to remove them it to cut them off (when routed over the idler as shown in your photo).

I was in full rage mode :banghead: during my belt replacement a few years ago because mine were previously routed over the idler and for the life of me I could not get the new belts to do the same (without resorting to a pry bar). After looking at the FSM and finding the correct routing the job was a piece of cake.:doh:
 
This is a fairly common mistake. Personally I’d replace them. OEM belts are reasonably priced. In either event make sure to correctly adjust the tension. Perhaps bring it to the shop’s attention and have them remedy the issue.
 
Edit - sorry I just realised the date of this thread. Got linked here from another thread thinking this was new. Sorry for digging it up....



To be fair to the workshop, if you don’t deal with 80 series a lot the logical direction is over the pulley as they’ve done. The design from Toyota is literally stupid (one of the rare things Toyota got wrong, like the headlight wiring, handbrake design etc).

So yeah, if you have the manual or work on these often you’ll know the correct path, but it may have been an apprentice who took the original belts off without paying attention.
 
To be fair to the workshop, if you don’t deal with 80 series a lot the logical direction is over the pulley as they’ve done. The design from Toyota is literally stupid (one of the rare things Toyota got wrong, like the headlight wiring, handbrake design etc).

I think it is less 'stupid' than one might think at first....when you consider the routing and the pulley's purpose.

The routing part doesn't need to even be addressed....as it is fine. It is the most direct, uncomplicated route and uses two belts for redundancy sake.

As for the pulley (the belts 'barely' contact) it is really there just to help alleviate belt flutter which can occur over long spans of unsupported belt. Even though many folks have done away completely with the pulley and experienced no ill effects.....Toyota nonetheless chose to 'cover all the bases'.

The pulley was never intended to be a 'tensioner' (in the true sense). That is evidenced by the fact there is NO adjustment to it.
 
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"To be fair to the workshop, if you don’t deal with 80 series a lot the logical direction is over the pulley as they’ve done."

I once was driving an 80 home (600 miles) after purchase and had to pull into
a small general repair shop to check the oil pressure. The mechanic, a very sharp guy, pulled up the information online (ALLDATA) for the 80 before he started working on it. All the diagrams and specs were right there (same as the FSM). The no oil pressure turned out to be a dead oil pressure sender.

Point is, any shop worth it's salt should have a paid subscription that has the specs and procedures for most any vehicle, including a LC, IMHO.
 
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It is a funny thing. By the standards of every other belt routing ever done on a car that I have seen, the incorrect way would be the logical way. I bet with correct length belts and tension, that scheme would also work with no noticable issues for a long time. But at the end of the day I joined team no-pulley myself and see no reason to put it back. Plus without it there, you also have no reason to worry about whether you get a cogged belt or not.
 
Right, but as mentioned above, it's not a spring loaded tensioner pulley, it's more of a guide, something to keep belts from fluttering/flopping up and down ie: so loose belts are less likely to pop off the alternator pulley (and maybe damage your radiator). IMO.

The way I look at it, the engineers who put it there know more about it then me, and it's cheap insurance.
 
It is a funny thing. By the standards of every other belt routing ever done on a car that I have seen, the incorrect way would be the logical way.

Agreed 100% IF it were intended to be a tensioner or were a serpentine belt. But I think what gets lost on folks is that the pulley clearly is there only to attenuate belt flutter. There is NO adjuster and no amount of tightening the belt will change the angle of the belt, its engagement to the pulley or pressure against the pulley (to any meaningful degree).

BUT.....I can fully understand how someone only taking a cursory look at it and having always dealt with tensioner/idler pulleys (that DO have the belt wrap around them), could make the mistake. I suppose if Toyota had seen fit to include a belt routing sticker under the hood...like they have for the emissions stuff....then it would help prevent this.

There really is no harm in running them that way (over the pulley), its just that it leads to the use of incorrect belts or frustration for those trying to install the correct ones.
 
Right, but as mentioned above, it's not a spring loaded tensioner pulley, it's more of a guide, something to keep belts from fluttering/flopping up and down ie: so loose belts are less likely to pop off the alternator pulley (and maybe damage your radiator). IMO.

The way I look at it, the engineers who put it there know more about it then me, and it's cheap insurance.

^^^^

Exactly right.

Important to remember that the engineers had to consider all of the probable conditions these vehicles would be used for (in over 150 countries).

Not just soccer Mom's or Corporate Lease Vehicles in the U.S. (when new).

Something like shock loading when the engine is revving high and you suddenly get off the throttle... takes the belts from a highly stressed condition to nearly coasting. This will distort the belt anywhere there are long sections unsupported and made worse if the belts are not properly tensioned.

Engineers thought of that (and more). I also like that they used two belts instead of one. Again...evidence they thought about creating a redundancy in a critical area. You lose your drive belt and you are royally screwed.
 
The belt routing sticker would have been a good idea. When I bought my 94' the belt was routed incorrectly and I assumed it was supposed to be that way until I tried to replace the belts and destroyed the new ones in the process (by using a prybar to get them over the idler pulley).

Looked in the FSM (should have started there but assumed belt replacement was simple enough without) and found the correct routing. Another set of new belts went on easily and I felt like an idiot. :bang:
 

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