I put on my dual alternator pulley today along with all the belts and no matter which way i put the belts one belt comes out tighter than the other.

one being loose and one being tight, and this is with the alternator as high up on the bracket as i can pull it and its still tight on one and loose on the other even when i swap the belts

 

the belts should be set to factory deflection. if one is tighter than another, you defeat the use of a dual belt set up. Are you using two new belts of the same exact brand and model???

and you should not be tightening "high up on the bracket as i can pull it ". That is a quick way to burn out the bearings in the alt and water pump.

 

[QUOTE=Icemark]the belts should be set to factory deflection. if one is tighter than another, you defeat the use of a dual belt set up. Are you using two new belts of the same exact brand and model???

yes they are both the same belts brand new from mazdatrix.com i checked the lengths and they are the same

and you should not be tightening "high up on the bracket as i can pull it ". That is a quick way to burn out the bearings in the alt and water pump.

if i dont pull it as tight as i can the looser belt will be so loose that it will fall off while the other is still on

maybe i have the spacer on the alternator in the wrong place ? is it suppose to be in the back or in the front ? i have no idea what the problem is but i changed where the spacer was before because the alternator/belts looked they were too far up with the spacer on the front

 

If the belts really are the same length size and age, then your dual belt pully is probably not the same size on both. who's dual belt pully are you using???

 

I noticed a SLIGHT variation in the HiggiTrix pulley, but its not enough to make any large difference. Could be variation in the Belts, but I run the exact belt. Dual Gatorbacks..

 

did you buy a "matched set" one where the two belts are attached tied or secured together forom the manufacturer If its not a true matched set you run risk of differences from batch to batch.

 

i think i may need to buy new belts because evenwhen i switch the belt the belt that was loose and the belt that was tight is still tight/loose even on the opposite end of the pulley so i think it must be the belts but i think i should be getting my money back from mazdatrix.com for giving me 2 different size belts

 

I think it's the alignment of the alt., 2 bolts can't hold it straight.
Take the ac compressor for example, it's got bolts fore and aft.
It's kind'of designed for one belt(the alt).
I have the dual, and have the same problem after a few miles.

 

banzaitoyota , rotaryinnovation.com

i believe it may be the belts , but by look of eye inspecting them they appear to be the same length but when on the car one is always loose no matter what side its on , and one is tight no matter what side its on .. so it must be the belts but why are there two belts that are truly identical ?

 

i think this is my problem right here but where can i get two belts that are an exact matched pair

 

I ran the Higgi dual belt pulley and two gatorbacks and one was slightly looser. Like you said it's probably variations in the belt. Normally cars don't have to run dual belt pullies, so I imagine they don't have to manufacture the belts within exact specs. As long as it is close, since they initially stretch anyways. But the slight variations didn't matter much since the tighter belt soon stretched to the same length of the looser belt. Besides, fault in the pulley would be unlikely since it is CNC machined, IIRC, and those are accurate within one ten thousandth of an inch, or something stupid like that. So yeah...

 

we're not talkingslightly loose we're talkin there is a big difference one is tight to the max tightness and the other is still loose

 

Is the loose one always closest to the engine, or opposite?, if it changes back and forth when you switch the belts then its the belts, if not, ^.

 

I have never heard of Banzaitoyota's ones ever having problems. I have to think it is either alt alignment or belts.

 

just go to almost any parts store. if they dont have them they can order. A matched set is two belts cut side by side off the same lot. I prefer gates belts.

 

I had this same problem with the FD alt I got from silverrotor.... after a while, I eyballed the pulley real close... the front sheve was about 1/8 of an inch deeper than the rear..... hence... looser belt.........

I ripped that POS off and got a HIGGI dual pulley and its all kosher now..

After a new set of belts that is....

 

I had the same problem, but it wasn't the pulley. I had to go back to the part store and compare five different belts to find 2 that were the same. As someone else said, dual pulley applications aren't considered when your generic part manufacturer produces a belt.

 

thats one hell of a set of eyeballs you have there. I have a silverrotor and it was fine. I installed a higgi for looks.

 

Exactly.... I went to NAPA and told them I was using a duel pulley system and they matched them for me. (same batch)

No issues whatsoever going on 2 years

 

I have a banzai toyota one and it is fine. I had the same problem as you when I bought the same belts with same part number and same manufacturer. I used them both but one being more loose ended up comming of and the other belt broke so I said let me try another brand and sure enough at autozone they gave me two of the same belts and they both fit perfect.

 

bought some gates belts from carquest today and the problem has been solved, goodlookin on the gates belts they costed my 19 dollars and change with tax

ill add to your rep for givingsome good advice on which belts to choose, i also called a few parts stores and they also recommended gates belts

 

Maunufacturing Tolerences are a bitch these days. I am going to go over to the GATES Factory here in my town (Yep I am lucky to have one) and see about getting some "matched" sets of belts.

Now if they make this style belt at the plant here in town

 

yes please! Start selling them and I will buy them because I think I just got lucky that my two I just bought where the same size.

 

a lot of ifs. Will they sell to me, do they make that style and size belt there, etc. I'll try

 

i have a question of my own about dual alt pullies is it alright to have a dual alt pulley and only use 1 belt on it because im still running with my airpump but with my new exhaust i dont think ill be using my airpump with it so ill be able to use 2 belts then but i want to keep my airpump in just for emmisions then switch back to dual belts