Why dual belts for the fan and alternator? (1 Viewer)

[John E Davies]

Did Toyota do this so that if one belt failed you could continue to drive, or is there so much drag there that a single belt is not adequate?

For the first time ever in my life (I'm 59) I blew a belt. The set was not that old - 15,000 miles/ three years - and they were a matched Toyota set. I always use a belt tension gauge to set the tightness as per the maintenance manual - no guessing.

Since the last time I checked the oil, one belt just broke. No squealing or smells. What's with that?

Anyway, this demonstrates to me that a "matched set" is not worth buying, and I am just going to use aftermarket belts from NAPA from now on. The sales guy said that when my truck was new, a matched set made sense, but current belts are made with very tight tolerances and you don't need to have them cut them off the same roll of rubber as they used to do.

Comments welcome!

Thanks.

John Davies
Spokane WA USA

 

[Stevesnj]

Did Toyota do this so that if one belt failed you could continue to drive, or is there so much drag there that a single belt is not adequate?

Thats it! Just a redundant belt thats all.

 

[Rwhat]

It's redundant. Luckily for you. The bright side of things is the matched set from Toyota is about the same price or cheaper than the auto parts store.

Also a lot of the auto parts store stuff as far as radiator hoses don't fit too good. I bought goodyears before. I doubt belts dont matter too much since their adjustable (ribbed belts will make noise).

 

[george_tlc]

My 1980 patrol runs dual belts too. It's just the way they built real vehicles until the serpentine belts came along...

cheers,
george.

 

[Howard705]

Look up industrial belt/sheaves-like Browning-they are designed for a horsepower load and have charts for each size-will add more-sometimes many to work properly.

 

[Funner]

I haven't heard of failure of OEM belt sets at that low a mileage. I have heard of poor results with aftermarket belts premature failure and noise. I would stick with OEM and chalk it up to a fluke. If it happened again, different story. How are the pulleys, any slop?

 

[hoser]

My understanding is dual belts is necessary to get the required friction. Just as there is 6,7,8 groove serpentine belts. There were many "road" vehicles that had the dual v-belt arrangement too.

 

[gray rider]

Get extra sets of oem belts for spares. Cheap insurance...

 

[Nonprophet]

The bright side of things is the matched set from Toyota is about the same price or cheaper than the auto parts store.

That depends upon whether you're buying for a 3FE or a 1Z.

For the 3FE, my dealer quoted me $150 for the set of 3 OEM belts, and the cheapest I could find OEM ones online was $89 for all 3. Compare that against $52 for a set of 3 belts from NAPA....

For the 1Z, the OEM belts are ridiculously inexpensive....

 

[western flyer]

On my 2F (FJ-60) the belts are very thick/wide, but not doubled-up like the 3FE and 1FZ-FE. that would match up with the friction issues noted above.

Since so many folks complain about aftermarket belts making substantial whining noise, and so few on here complaining about OEM belts failing (or making noise), I think it would be worth it to call beno, CDan, or Sam Steward and pay the extra 40 bucks (or much less) to get the OEM ones. I too would chalk it up to a a fluke failure. The 1FZ betls are pretty cheap from these guys.

 

[inkpot]

Look up industrial belt/sheaves-like Browning-they are designed for a horsepower load and have charts for each size-will add more-sometimes many to work properly.

I think this is the biggest reason for the double belts. A single belt in this position would be more prone to fail due to the work load. If you are running a souped up fan clutch, it is even more important that those belts are in really good shape. I wasted a set of OEM belts in right on 3 years, about 40,000 miles. John

 

[John E Davies]

Thanks for the comments. I'll order a set of OEM alternator belts from cruiserdan the next time I place an order. I needed new belts ASAP, so I am going to give these NAPA belts a try for now. If they whine, I'll just replace them with the good ones.

John Davies
Spokane WA USA

 

[livinoffroad]

Look up industrial belt/sheaves-like Browning-they are designed for a horsepower load and have charts for each size-will add more-sometimes many to work properly.

^^^This^^^
When I was in the "material handling industry" (read quarry) Many of the conveyor belts were driven by large electric motors which had 2,3,and 4 belt sheaves, so that if one broke, it avoided catastrophic shutdown.

 

[BlackLS1]

When I got my rig last year it still had the original
Toyota belts from 1994. They were cracked badly
and we're making noise. Amazing how they dident snap yet being that old.

 

[diego355]

The reason for the dual belts is in case that one breaks you are not stranded in the middle of the road. The vital components are always "insured" by the 2 belts

 

[hoser]

The latest Land Cruisers don't have dual serpentine belts.

 

[John E Davies]

I ordered two sets of belts from cruiserdan. They are MUCH easier to install (slightly longer than the NAPA ones) and dead silent. I put the second set in my spares kit and have learned a lesson.

I am going to see if I can get a refund from NAPA - they are great guys and very friendly, but since these have been installed I don't know if they will take them back.

BTW, I use a Krickit belt tension gauge to set the belts to the specified tension - 60 to 100 pounds. Since the fan belt is a double set, I used half that per belt.

http://www.youtube.com/watch?v=z11wfc-0-hY

John Davies
Spokane WA USA

 

[Impreza]

I ordered two sets of belts from cruiserdan. They are MUCH easier to install (slightly longer than the NAPA ones) and dead silent. I put the second set in my spares kit and have learned a lesson.

I am going to see if I can get a refund from NAPA - they are great guys and very friendly, but since these have been installed I don't know if they will take them back.

BTW, I use a Krickit belt tension gauge to set the belts to the specified tension - 60 to 100 pounds. Since the fan belt is a double set, I used half that per belt.

http://www.youtube.com/watch?v=z11wfc-0-hY

John Davies
Spokane WA USA

Just keep them as a lesson learned and spares, it's kind of a dick move to return something that is perfectly fine and used. Now if they were truly defective, that is another story.

 

[e9999]

snip

BTW, I use a Krickit belt tension gauge to set the belts to the specified tension - 60 to 100 pounds. Since the fan belt is a double set, I used half that per belt.

http://www.youtube.com/watch?v=z11wfc-0-hY

John Davies
Spokane WA USA

the 1/2 specified tension bit sounds a bit odd. You sure?

 

[08720]

it's kind of a dick move to return something that is perfectly fine and used. Now if they were truly defective, that is another story.

X2 on this