My Maverick now sports a 100 amp reman alternator from an '85 F250 diesel! The problem is (was!) basically if I was idling, I could run any two of the following and not show a drain on the ammeter: Headlights, cooling fan, stereo, wipers, blower, turn signals or sport lights. Get three or more of those items going and I would show some drain at idle. Run like that for long enough and the lights start to go dim, the amplifier cuts out, and I just might fry the regulator. Done that a few times actually. Occasionally if I shut it off without driving around a little bit I might not even get it cranked again. This was with a perfectly good, new alternator, several new regulators, all new wiring, no bad grounds or shorts of any kind anywhere. Lame! So after three attempts, I finally scored. First I tried a Delco unit from a Cadillac, but I didn't like the way I had to rig the bracket and it didn't give me the juice I wanted at idle. Second one was a dud. Then today after I'd just bought yet another regulator, the weather was right so I decided on a whim to take a detour to the Pull-A-Part. I know I could have just bought a new one, but I didn't want to spend that much money until I knew I had what I wanted. And for under $20 apiece, I can afford to experiment. After a bit of looking I found a likely candidate. Somewhat oversized alternator on a diesel rig with obvious electrical upgrades. Big fat cables under the hood that didn't look stock. Some holes in the bumper and bed made me think it was probably a tow truck with a winch at one time. And everything under the hood was dirtier than the alternator so I thought it was probably newish. Sure enough I see the Duralast sticker, "REMAN 100 AMP." Sold! After hosing it off with brake cleaner and Simple Green, it looks brand new. It bolted right on to my bracket using a shorter belt. I figure maybe the regulator for that alternator could be different than the one for the Mav, so I used the one that was in the truck. Yes it is externally regulated, but that's okay. I have blown up more regulators than alternators, and I can't help but think some of the alternators I've killed were probably fine except for the internal regulator. And regulators are cheaper to replace anyway. I also chose not to go the 3g route because I like to run an ammeter, so this was really perfect. I fired it up and at first I face diappointment. At idle, I have more drain than usual. Can't run even two of the aforementioned accessories. Well damn, maybe I have it wired wrong. Nope. But before I accept defeat again I decide to try the new regulator. Success! When I start it up it's already showing a charge. Alright, let's turn some stuff on and see what happens! Headlights, sport lights, flashers, stereo, blower, even the wipers. Kick on the high beams too! I turn it all on and STILL it shows a charge at idle! It's even idling a little faster than usual. I think my ignition system must be enjoying this. I haven't driven it around much yet, but it wouldn't surprise me if it runs cooler too, since my fan will be getting enough power. So for future reference guys, that's a good one to look for and you don't have to change much to wire it up. Only change really is I used the fatter wire and fusible links from the truck. My only complaint so far is it's still got a 2-groove pulley and I intend to change it to single groove. Otherwise, I am extremely happy about it! This was the last little driveability annoyance I had to deal with, so I can now say this is a solid driver and I'd confidently go anywhere in it!
thats awsome to here ,i put a 3g 130 amp in mine and i have no complaints either. it works and does everything i want it to do. cheers James
I do have one concern now, about using the stock type Maverick regulator with the bigger alt. I looked up the regulator for the donor truck and it is in fact different, although it looks the same. VR730 and VR749 are Auto Zone's part numbers. Anybody know whether this is okay? Or should I just run it 'til something breaks and then report back? It seems to be working fine... And a side question, just to satisfy my curiosity. While I was plundering the junkyard I saw at least three distinct types of Ford voltage regulators. The early stuff, say a 72 Ford truck, had a regulator that looked like mine in every way except the case is a lot thicker. Yet I looked that up and see that it takes the same part as the Mav. Is this just an old school, non-solid state "mechanical" regulator?
Most likey the same part, just different case. People tend to cut back on material to cut costs. I've bought the same regulator for every ford vehicle I've owned that used external regulators. I always just ask for a 79 F-150 regulator. Never had any problems
That would be VR749, same as that F250 diesel. I think I've figured this out. I looked up a '79 Granada to see whether it was a car vs. truck thing, and that Granada showed it using both, depending on the alt: (These are Wells part numbers, not just Auto Zone, so this should be good at other places) VR730 - 40, 55, 60, 65 Amp. VR749 - 70 or 100 Amp. That's kinda what I thought anyway. So I guess I'd better exchange that regulator for the bigger one. (Not that I actually understand the difference yet, but let's not risk ruining a good thing over ten bucks...)
Got an update... While Auto Zone lists two different Wells voltage regulators for the different amp ranges, turns out Advance (Checker, Kragen) lists only one, and that's the one I actually have. BWD part number VR301 is apparently good for all of them. So I kept that and have been running it without a problem so far. Also I got a puller and swapped out that 2-groove 3" pulley for a single groove 2" one. Now it looks like it actually belongs there, and should help a bit at idle. No squealing yet.
If you went to a smaller pulley, you have changed the rpm that the alternator sees and the charge rate. A diesel alternator will be set up to run it's highest at lower rpms. Running higher rpms, combined with raising the rpm with a smaller pulley may cause problems. Just a thought. You might look for a larger diameter single pulley, or even pick up a Moroso underdrive pulley. It should make the alternator last longer, as well as prevent any overcharge or wiring overheating condition that might be caused by these factors.
I thought about that, but then I saw it's the same Duralast part number listed for several other Fords with gasoline engines, not specifically set up for diesel. '85 Lincoln Continental for instance, even says "Pulley change required." The website shows at least three different pulley/fan combos on there, like these: There's the 3" pulley. This is what I started with. Here's a 2" pulley with a funky fan... Another 2" pulley with the same fan as the frist one. This is what I've got now. I may be wrong. These alts might have nothing in common with each other but the case and the part number, but I don't think so. If it turns out I am wrong I will report back. You ought to know by now I'm not ashamed to tell the mmb about my stupid mistakes... Voltmeter and ammeter are telling me I'm in good shape though. I get a nice healthy 14-14.5 volts and no higher. The ammeter hasn't yet gone above ~35 amps no matter how fast I spin it. (Sounds low for a 100 amp alt, but that's over and above the electrical load, ie if the alt wasn't turning it would probably show at least a 40 amp drain with the typical stuff turned on, so that's about right. Counting starts below zero.) I don't think the VR is going to let me overcharge the battery, and unless my ammeter is wrong there's not enough current moving to fry my wiring, (which is not stock) so I think I'm ok. Next time I'm at the junkyard I just might find myself a 3" single pulley though, just in case.
well put... when i swapped to a 3G, i went with an early style underdrive pulley (they came on 'K' code Mustangs). it's a factory underdrive pulley, but it doesnt have too much underdrive, just enough to change it a tiny bit. in turn, my alt and wiring and always cool to the touch and it still charges extremely good unless they're insanely hard to find, i'd try to find a 3G around there. this way you know everything will work accordingly and it internally regulated
