Finally putting a 3g alternator in my highboy

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03-27-2011, 11:18 AM

akforceten

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Finally putting a 3g alternator in my highboy

I had originally posted this in my I love my new radiator and electric fan thread but thought this should be in a new thread. So here it is! The new radiator and T-Bird fan are doing great! There only is one downside that I have experienced. While driving at low speeds or around downtown my volt gauge only shows the alt only putting out 12-13 volts. Well today I fixed the problem by converting to a 3G alternator. Now the volts are 14.8-15 volts at low speeds or running down the freeway! Well here's some pic's( I love taking lot's of pictures of thing that I do to my truck) The only problem I have is sometimes I forget to take the pic's(I get to excited doing the upgrade)

This what I'm replacing a chevy 100 amp alternator . Couldn't keep up with the electrical demands

Here's the new / used alternator ! I'm taking the front case loose so I can clock it for the 390 .

Clocking all done . I had to replace the stator cause it tested bad .I took it back for another test this time it passed . As you can see I'm re-tapping the tension adjusting bolt hole to a 3/8 coarse thread bolt, also put the v pulley on had to use a washer for spacing.

I got it in now the fun begins ! It's time for wiring hooray!

I'm finally done wiring it in .It was really simple should have done this from the beginning ! It's time for a test drive and so far everything is working great!

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03-27-2011, 11:49 AM

wyckedcombo17

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Good stuff! I'm looking to do this to my truck soon too. Was it pretty much a bolt in kind of deal? Or did you have to do a lot of messing/fabbing?

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03-27-2011, 11:54 AM

akforceten

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Only to clock the alternator so the batt connection wasn't against the block and tapping the adjuster bolt hole to 3/8 coarse thread otherwise bolted in.

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03-27-2011, 01:17 PM

kingford72

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this was the best thing I ever did

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03-27-2011, 04:46 PM

F-250 restorer

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I did mine quite some months back. Due to squealing I finally had to put on a double v belt pulley to stop the squeal. If it would kick into charge at a light, I could hardly get through the intersection because it squealed like a pig about to be slaughtered!!

I assume you put in a mega fuse to the alt? 175 amp?

I also pulled an extra from the j/y and keep it behind the seat in case of failure. You got to love it, two alts for less than the cost of a new one!

I'm wondering if you ever did that hydroboost upgrade you were thinking about.

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03-27-2011, 08:33 PM

akforceten

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Yes I did use a 175 mega fuse. Hydoboost is next on the list had to deal with the cooling problems then the failure of the one wire chevy alternator . I also had the intake gasket start leaking coolant and oil real bad so I took care of those first ! Now it's time for brake upgrades of coarse I will post the hydro boost upgrade when it happens

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