Need larger Alt.
Senior User
Joined: Apr 2000
Posts: 321
Likes: 1
From: Minnesota
Need larger Alt.
I am just finishing modifying my 84 F-150 2wd to a F-350 4x4. The problem I have is that I installed a rebuilt 351w, but kept the alt and voltage regulator from the original I-6. The truck is going to have a plow installed and down the road a winch. I was just wondering how and what I have to replace to install a larger alt. It has an external voltage regulator.
Also, what size alt and type should I go with?
Thanks Mudman.
1984 F-350 4X4
1986 F-150 4X4
1977 F-250 2wd
1995 T-bird
Also, what size alt and type should I go with?
Thanks Mudman.
1984 F-350 4X4
1986 F-150 4X4
1977 F-250 2wd
1995 T-bird
Senior User
Joined: Nov 2000
Posts: 231
Likes: 2
Need larger Alt.
There is not much in the way of modifications to make a larger alternator work. You may need to shorten the spacer behind alt. where bolt goes through and maybe grind a little on tension arm (to fit larger case) but I believe that is it. Go with a large case 90 or 100 amp alt. you can find them on all sorts of mid-80's Ford cars from a Lincoln to an Escort. I've installed a 100 amp alt. in place of the 55 amp model and have had NO problems at all. You won't need to change voltage regulator because as it says, it regulates voltage, not amperage. I hope this helps in any way.
Todd
BB79RANCH
Todd
BB79RANCH
Fleet Mechanic
Joined: Aug 2000
Posts: 1,504
Likes: 1
From: Texas
Need larger Alt.
My fathers 82 F-150 had the 300, and his had a good size alternator from the factory. I can't exactly remember what the rating was on it, but it was more than 60. Try calling around to some of the parts houses, and see what they offer. I know ford ran some of the stock alternators up to at least 90.
[link:www.geocities.com/hotrodford_88/|Hotrodford_88's Webpage]
[link:www.geocities.com/westlake_vfd/Westlake.html|Westlake VFD Website]
[link:www.geocities.com/hotrodford_88/|Hotrodford_88's Webpage]
[link:www.geocities.com/westlake_vfd/Westlake.html|Westlake VFD Website]
Senior User
Joined: Mar 2000
Posts: 425
Likes: 0
Need larger Alt.
Where do you find the size of the alternator installed, I only ask because of the stereo I have installed, and lately the battery has been dying rather fast (since install of the 1200 watt amp, teehee)
1995 F150XL - Reg cab/bed, 4.9L, 5-speed, Metallic Navy Blue/Gray int.
Mods: Tanno cover, bed-liner, 1200 watt Crunch amp, 2 10" Rockford Punch Subs, sony cd-player, K&N Filter, Flowmaster 40 series w/ no visible exhaust exit, BFG A/T 31"x10.5"R15 & Rancho RS5000 shocks
1995 F150XL - Reg cab/bed, 4.9L, 5-speed, Metallic Navy Blue/Gray int.
Mods: Tanno cover, bed-liner, 1200 watt Crunch amp, 2 10" Rockford Punch Subs, sony cd-player, K&N Filter, Flowmaster 40 series w/ no visible exhaust exit, BFG A/T 31"x10.5"R15 & Rancho RS5000 shocks
Fleet Mechanic
Joined: Aug 2000
Posts: 1,504
Likes: 1
From: Texas
Need larger Alt.
Kevint,
Your best bet on an alternator for your truck would be one out of the Summit racing catalog. Now they run $180.00 but they are 140 amp alternators. I don't have the catalog in front of me right now, but they are supposed to be good units. The only question I have on them is that they say they are only for V-belt systems. But yet they list them for 87-96 Ford trucks. Hmmm, maybe I should call and ask them, what do you think.
Of course maybe I need a bigger alternator since I installed that lightbar on the roof of my truck. Especially since when I turn the lightbar on I can hear the truck idle down, (almost like it says "oh help me!"). What do you guys think?
Take a look at my webpage and you'll see what I mean!
[link:www.geocities.com/hotrodford_88/|Hotrodford_88's Webpage]
[link:www.geocities.com/westlake_vfd/Westlake.html|Westlake VFD Website]
Your best bet on an alternator for your truck would be one out of the Summit racing catalog. Now they run $180.00 but they are 140 amp alternators. I don't have the catalog in front of me right now, but they are supposed to be good units. The only question I have on them is that they say they are only for V-belt systems. But yet they list them for 87-96 Ford trucks. Hmmm, maybe I should call and ask them, what do you think.
Of course maybe I need a bigger alternator since I installed that lightbar on the roof of my truck. Especially since when I turn the lightbar on I can hear the truck idle down, (almost like it says "oh help me!"). What do you guys think?
Take a look at my webpage and you'll see what I mean!
[link:www.geocities.com/hotrodford_88/|Hotrodford_88's Webpage]
[link:www.geocities.com/westlake_vfd/Westlake.html|Westlake VFD Website]
Posting Guru
Joined: Apr 2000
Posts: 1,345
Likes: 0
From: NorCal
Need larger Alt.
I replaced my stock 75 Amp on my 90 F-150 300-6, with a Ford 85 Amp after the original one froze up. The parts guy brought out two, one with the brushes/voltage regulator and one without. The one with had a 85A stamped on the case while the one without had a 75A. I went with the 85A of course. Pricey at 180 from the dealer, but worth it. It hasn't let me down yet. But thats a newer truck.
On your truck, I'd go with a Bosch alternator, they're the best quality and performance wise, for the cost and availabilty. And besides, those are the ones that all the mobile-welders use.
Although, given the opportunity, I'd go with Mean-Green http://www.mean-green.com/ . They are by far the best (starters too, high torque & low amperage) but also a little more pricey. But hey, that's just my opinion. I'd check into it, especially for a high draw (stereo, winch, welder, etc) system.
On your truck, I'd go with a Bosch alternator, they're the best quality and performance wise, for the cost and availabilty. And besides, those are the ones that all the mobile-welders use.
Although, given the opportunity, I'd go with Mean-Green http://www.mean-green.com/ . They are by far the best (starters too, high torque & low amperage) but also a little more pricey. But hey, that's just my opinion. I'd check into it, especially for a high draw (stereo, winch, welder, etc) system.
