idle pulley question (1 Viewer)

[oc cruiser 97]

I have a 97 land cruiser fzj80 , i recently replaced the alternator and Ps pump . after i started up the engine the idle pulley was slightly squeaking . after several attempts to adjust the belts ect ..... I removed this pulley . no more noise !! Is this harmful to the drive belts system or engine ?? is this pulley necessary ? If any diagrams of the belts are available , i would appreciate it .
I am new to this forum . I was along time ago (35 years +) a land cruiser owner , and have rejoined the addiction again !!

thanks Marc

 

[baldilocks]

Welcome to Mud. A lot of members run fine without the idler pulley. Did you route the belts on the lower side of the roller? Are your belts the corrugated type with “teeth” at the inner diameter? This will make noise in the idler roller. Toyota belts are smooth. You can buy the entire pulley with the bearing fairly cheap.

 

[Clemson TLC]

I have replaced mine twice (180K miles), last time in the last few weeks. There are previous threads if you search on idler pulley. Several folks run without it. It is supposed to reduce belt slap, but since the compressor is not on those belts, I'm not sure how much there is. There is even a Youtube on how to replace the bearing in if you are too cheap to buy a new one ($40 on Amazon). The oil pump may leak without the bolt installed.

https://www.amazon.com/gp/product/B00KTI63PO/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

Here is a cheap tool for checking belt tension:

https://www.amazon.com/gp/product/B000MUTAGS/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

 

[oc cruiser 97]

Great thanks for the info , the current belts which are new are corrugated (with teeth) . I have test driven since the work was done , and don't seem to notice any issues with the belts . I did leave the bolt in place , so no oil leaks . I may buy from the amazon site , and keep the new part just in case there is an issue later .
Marc

 

[MoJ]

It’s possible that the pulley was nearing the end of its life anyway and the tighter belt, even within spec, simply revealed the pending failure. Check the belt tension with the cricket gauge and replace the pulley.

 

[BILT4ME]

I drove my truck for 25K miles before I realized there was SUPPOSED to be an idler pulley there. (PO had removed it)

I experienced a belt failure that contributed to an exploded radiator that I believe was attributed to the cog-style belts and no idler.

I was WOT coming onto the interstate with the AC on. At WOT, the AC kicks off to allow better acceleration. As soon as I let off a little, the AC kicked on and broke the belts (possible surge and slap due to no idler), the belts wrapped around the water pump, stopping it.

There was a sudden temp increase, the radiator cap couldn't relieve fast enough (it too was clogged up) and the top of the radiator split open. It sounded like I blew a tire.

So, since then, I am now running Toyota factory belts and have added a new idler pulley and bolt. No issues in another 45K miles.

 

[Cass007]

I ran w/o the idler on my 97 LX for years and the idler on my 97 Cruiser is stuck in 1 place and waiting to be replaced. My truck seemed fine w/o it, but I'm sure the engineers had a reason for them being there, so they are going back on the LX now. I also had the cog-style belts and as the belt wore in a bit it sounded like the truck had a SC on it. OEM belts are nice and quiet now.

 

[richardlillard1]

I drove my truck for 25K miles before I realized there was SUPPOSED to be an idler pulley there. (PO had removed it)

I experienced a belt failure that contributed to an exploded radiator that I believe was attributed to the cog-style belts and no idler.

I was WOT coming onto the interstate with the AC on. At WOT, the AC kicks off to allow better acceleration. As soon as I let off a little, the AC kicked on and broke the belts (possible surge and slap due to no idler), the belts wrapped around the water pump, stopping it.

There was a sudden temp increase, the radiator cap couldn't relieve fast enough (it too was clogged up) and the top of the radiator split open. It sounded like I blew a tire.

So, since then, I am now running Toyota factory belts and have added a new idler pulley and bolt. No issues in another 45K miles.

So your idler pulley is somehow more special than mine? I removed mine about 75,000 miles ago and have not seen any difference despite using top cog belts or belts with cogs on the bottom.

This is in Phoenix, where I use my AC about 8 months of the year. I doubt the AC kicks off at wide open throttle, do you have anything to back this up?

 

[Tools R Us]

...
I experienced a belt failure that contributed to an exploded radiator that I believe was attributed to the cog-style belts and no idler.
...

My guess, that had nothing to do with it. Know of several that have run cog belts and no idler for over a decade, zero issues. If anything have had better life/reliability with good aftermarket belts than cheap dealer belts.

 

[BILT4ME]

So your idler pulley is somehow more special than mine? I removed mine about 75,000 miles ago and have not seen any difference despite using top cog belts or belts with cogs on the bottom.

This is in Phoenix, where I use my AC about 8 months of the year. I doubt the AC kicks off at wide open throttle, do you have anything to back this up?

I'll see if I can locate the info. It may take me a while. Anyone else that can verify or debunk for sure is welcome.

Obviously my PO ran without it for a LONG time. There are a number of "unnecessary" things removed from my engine......Idler pulley, Alternator adjusting bracket (It was pried outwards and then the bolts tightened in place), Cylinder head covers #2 and #3 (the plastic things that cover the spark plug wires.....)

I have reinstalled most except the cylinder head covers.

My guess, that had nothing to do with it. Know of several that have run cog belts and no idler for over a decade, zero issues. If anything have had better life/reliability with good aftermarket belts than cheap dealer belts.

How would having the belt failure "that had nothing to do with it."? It STOPPED the water pump, causing a spike in temp. When the temp spiked, pressure went up, radiator cap didn't relieve (yes, that was the primary factor). I said ATTRIBUTED TO, not CAUSED.

Either way, I took it back to factory spec (because some damn engineer designed it that way!) so that's the way I'm gonna run it!

 

[richardlillard1]

I'll see if I can locate the info. It may take me a while. Anyone else that can verify or debunk for sure is welcome.

Obviously my PO ran without it for a LONG time. There are a number of "unnecessary" things removed from my engine......Idler pulley, Alternator adjusting bracket (It was pried outwards and then the bolts tightened in place), Cylinder head covers #2 and #3 (the plastic things that cover the spark plug wires.....)

I have reinstalled most except the cylinder head covers.



How would having the belt failure "that had nothing to do with it."? It STOPPED the water pump, causing a spike in temp. When the temp spiked, pressure went up, radiator cap didn't relieve (yes, that was the primary factor). I said ATTRIBUTED TO, not CAUSED.

Either way, I took it back to factory spec (because some damn engineer designed it that way!) so that's the way I'm gonna run it!

I believe he is saying that your lack of idler did not cause the belt failure, which I agree with because that conclusion doesn’t make any sense.

Your belts failed, probably because the OEM belts are garbage trash.

 

[BILT4ME]

I believe he is saying that your lack of idler did not cause the belt failure, which I agree with because that conclusion doesn’t make any sense.

Your belts failed, probably because the OEM belts are garbage trash.

It's good you think that's the case on calling the belts trash....
Because the ones that failed were GATES cogged style.
And yes, I have normally LOVED Gates belts. Just not on this one.......

If you sharpen your reading skills, i took the truck BACK to factory. The PO had cobbled MANY things on this one just to get by.
FWIW.....

 

[richardlillard1]

It's good you think that's the case on calling the belts trash....
Because the ones that failed were GATES cogged style.
And yes, I have normally LOVED Gates belts. Just not on this one.......

If you sharpen your reading skills, i took the truck BACK to factory. The PO had cobbled MANY things on this one just to get by.
FWIW.....

Okay, so they were gates belts. The stupid idler still has nothing to do with it.

My case on the OE belts being junk is because they don’t last even half as long out here in AZ as others have.

I’m glad you went BACK to factory because Mr T is infallible can do no wrong.

 

[BILT4ME]

Okay, so they were gates belts. The stupid idler still has nothing to do with it.

My case on the OE belts being junk is because they don’t last even half as long out here in AZ as others have.

I’m glad you went BACK to factory because Mr T is infallible can do no wrong.

Since you seem so knowledgeable, WHY is the pulley NOT needed? Do you know WHY the engineers required it in the first place?

 

[-Spike-]

@BILT4ME- I wouldn't be surprised if the A/C belt broke, and the flapping pieces took out the other two belts. I am also skeptical that the idler pulley had anything to do with it. No one but the Toyota engineers can answer the question of why it's there. I am usually of the same mind as you when questioning their designs, but in this case the pulley doesn't seem to add anything to the equation. The distance between the pulleys is rather short, the belts shouldn't require support there, and the belts barely touch the pulley.

 

[richardlillard1]

View attachment 1619230
Since you seem so knowledgeable, WHY is the pulley NOT needed? Do you know WHY the engineers required it in the first place?

I’m only saying it isn’t needed because a ton of rigs are running without it and zero issues.

As to why, I don’t know, nor do I care.

 

[BILT4ME]

I’m only saying it isn’t needed because a ton of rigs are running without it and zero issues.

As to why, I don’t know, nor do I care.

Exactly. So stop bagging on me for taking it back to stock.

The Mr. T engineers may not always be right (HG first run, window motor speed) but they are certainly smarter than I. I will defer to their knowledge.

 

[richardlillard1]

Exactly. So stop bagging on me for taking it back to stock.

The Mr. T engineers may not always be right (HG first run, window motor speed) but they are certainly smarter than I. I will defer to their knowledge.

I’m not bagging on you. I bagged on Toyota a little, but not on you personally.

I guess this is because I disagreed with you? I’m confused here.

 

[BILT4ME]

I’m not bagging on you. I bagged on Toyota a little, but not on you personally.

I guess this is because I disagreed with you? I’m confused here.

Nah.....No worries. I must be spotting.....

 

[oc cruiser 97]

It would appear that the consensus is you can run the LC without the pulley safely .

Marc