1G V-belt Pulley on 3G alternator?

[ak68]

Will the V-Belt pulley from the 1G alternator fit the shaft on the 3G alternator? Will the 3G fit the same space and location as the 1G on 351w? Thanks!

 

[Ryan]

Will the V-Belt pulley from the 1G alternator fit the shaft on the 3G alternator?

yes, but it will bottem out on the case because the 3G doesn't have an external fan.

Will the 3G fit the same space and location as the 1G on 351w? Thanks!

Typically yes it will: http://fordfuelinjection.com/?p=75

 

[ak68]

Thanks Ryan,
It sounds like the v-belt pulley on the 3G is a problem. Will I have to convert to serpentine in order to run an internally regulated alternator or is there any way to run the 3G with a v-belt pulley? I just bought a set of march v-belt pulleys that I'd like to keep.

 

[la77]

I'm running the pulley that came off my stock alt on my 3g now without any problems. it is a 2 groove alt pulley though and not sure about the differences between 1 and 2 groove pulleys

 

[70_Steve]

I'm running the single v-belt pully that came stock on my 70. It's real close to the 3G case, but it works. Occasionally I get a little belt squeal when I first start up, but other than that, the single v-belt has been fine. Then again, I don't have a lot of accessories pulling extra current yet.

 

[nutter3]

AK68,

You can run a 1 groove V-belt pulley on a 3G alternator. I put one on my bronco last year, it works great. If i remember correctly, the original pulley fit on the shaft of the 3G, but it wouldnt seat deep enough (or maybe it was too deep--cant remember). A friend of mine had a pulley with different backspacing; we put it on and it worked great.
My bronco is in Anchorage, when I return to town from work, you could take a look at it if you want.

Andre

 

[ak68]

it works

I got a 3G and installed it today with my March V-Belt pulley. It works fine.
Getting close to starting my 393w for the first time. It has taken a long time but the end is in sight.

 

[Duke Nukem]

I used to run a v-belt pulley on my 3G. It worked fine but I ended up with a lot of belt squeal. Recently I converted to a serpentine belt and all is good.

 

[BwoncoHowie]

smaller pulleys will squeal easier than larger ones there are pros and cons.

Smaller pulleys spin the alt faster and create more charging power at lower engine rpms. the down side is that the belts squeal easier, they use more horsepower, they wear out faster, and high engine rpms can destroy the alt.

Larger pulleys spin the alt slower, which = lower output at idle and lower rpms but you actually have more belt contact with the pulley combined with higher leverage making the alt easier to be turned by the engine. This makes the belt less prone to slip and make noise.

For example, I'm running a 2 7/8" diameter v pulley with no issues on low rpm output or belt noise. If your pulley is smaller than 2 7/8", you might consider trying a bigger one. I kept looking in self serve wrecking yards and picked up a handful of pulleys in various sizes. Then after experimenting chose the one that worked best for my purposes. I would love to go serpantine on my engine but cant afford it right now.

weather the alt has a large or small pulley, charging system demands also play a key factor on if your belt will slip or not.
~BH~