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Narrow Belt Conversion

  • Thread starter Thread starter TRDejaVu
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TRDejaVu

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I am making the change on the TR4, although I am staying with the Generator for now. Anyone know which NAPA belt number will work?
 
Not sure -- I went with the Denso alternator, and that changed things. Which brings me to my point: They come in 1/2" increments. The folks at my local Napa were happy enough to sell me several of them to try the fit. I returned all the ones that didn't, and kept the one that did. Assuming you're not too far from the Napa store, it's a workable way to get just the right belt.
 
Not clear to me whether you want the NAPA wide belt for the generator (possibly 25-24379) or the narrow belt you will need when you install the alternator (it depends).
 
Geo Hahn said:
Not clear to me whether you want the NAPA wide belt for the generator (possibly 25-24379) or the narrow belt you will need when you install the alternator (it depends).
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I have obtained narrow pulleys for the crank, water pump and the generator.
 
When I got the narrow belt conversion, it came with the narrow belt. Since I was installing an alternator, the belt they gave me turned out to be too short. The belt they sent was a Quinton Hazell QBA<span style="font-weight: bold">975</span>. The belt NAPA gave me was a 7385, which is 9.5/10mm x <span style="font-weight: bold">995</span>mm (25/64"x39-1/8"). You most likely need the NAPA size closest to 975mm. Probably one or two sizes smaller then the 7385.

Hope this helps.
 
Thanks Art.

The outside diameters of the pulleys are 5 1/2" (crank), 4" (water pump) & 2 3/4" (generator). I presume that the crank and water pump ODs do not change, but I don't know if the alternator pulley is a different size. How do those sizes compare to yours?
 
Pretty hard for me to measure the crank and w/p pullies, but if they aren't the sizes you mentioned, they are very close as best I can get in there to measure. The generator pulley I did not use, as I have an alternator on there. It measures exactly what your's does.

As far as the alternator goes, the QBA975 belt would've fit, except for the fact that the alternator is fatter then the generator and hit the block before I could get the belt on. I couldn't push it toward the engine as far as the generator will go. That's why I had to go for a longer belt. The alternator also has a 17mm shaft, and the generator has a 15mm shaft. That's why I didn't use the pulley that came with the kit. Besides, the alternator came with a pulley already attached.
 
My local NAPA say they have either a 970 or 985 equivalent so I will try them. Thanks again and I will post info on which one that fits.
 
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