ArdWrknTrk Posted December 8, 2019 Share Posted December 8, 2019 Jim - Thanks. I missed this. And it has taken me a long time to get my head around it. Operative word is "has" as I'm not sure it is in the past tense. In any event, we do have two Lester #'s posted here: Documentation/Electrical/3G Conversion and on the Choosing An Alternator tab. But if you have more please post them here and I'll get them included. (And if you already have and I've missed that then I'm sorry.) Ok, I believe those numbers are for the 8.25" 130A with a tapped hole, and without a tapped hole. Or maybe they come with different clocking... If I can get some time to go digging I will try to get the 7" numbers and the numbers for both sizes of 95A alternators. This takes time on my phone because of the lack of tabs and the need for me to zoom in order to read the charts. The DB Electrical site then lists the Lester numbers once you have the proper application. (at least that's how I do it) It's a shame Bills son Matt doesn't distribute parts any more. I'd imagine he had all that information at his fingertips. Link to comment Share on other sites More sharing options...
fords4life Posted December 8, 2019 Author Share Posted December 8, 2019 The mounting holes also come in two 'flavors', 7" C-C and 8.25" C-C. If you have swing mount you want 8.25". If you have a fuel injected engine with a polygroove belt (except for 300 I-6) you want the 7" model. This is where my confusion is. I have a 1986 EFI 302 with v-belts. Since the truck is at my Dad's house, I had him measure and he said the mounting holes are 7" C-C which doesn't match up with what you stated above. I can't find a drawing of a 7716 alternator to confirm what the spacing should be, but the sticker down below would indicate a 7716-10 alternator, which from what I can find is supposed to be a poly groove belt application. Assuming I have a red headed step child. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 8, 2019 Share Posted December 8, 2019 The mounting holes also come in two 'flavors', 7" C-C and 8.25" C-C. If you have swing mount you want 8.25". If you have a fuel injected engine with a polygroove belt (except for 300 I-6) you want the 7" model. This is where my confusion is. I have a 1986 EFI 302 with v-belts. Since the truck is at my Dad's house, I had him measure and he said the mounting holes are 7" C-C which doesn't match up with what you stated above. I can't find a drawing of a 7716 alternator to confirm what the spacing should be, but the sticker down below would indicate a 7716-10 alternator, which from what I can find is supposed to be a poly groove belt application. Assuming I have a red headed step child. Does your alternator swing, and use a quadrant for an adjuster, or is it mounted to an aluminum casting, and sit pretty much on top of the engine? Link to comment Share on other sites More sharing options...
fords4life Posted December 8, 2019 Author Share Posted December 8, 2019 Does your alternator swing, and use a quadrant for an adjuster, or is it mounted to an aluminum casting, and sit pretty much on top of the engine? Mounted on the bottom left and it swings. I didn't get a good photo straight on, but below shows the mounting ear for the side that swings. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 8, 2019 Share Posted December 8, 2019 Mounted on the bottom left and it swings. I didn't get a good photo straight on, but below shows the mounting ear for the side that swings. So, if you want the 130A you should get the 8.25" If you want the 95A I think you could use the 7"C-C. Link to comment Share on other sites More sharing options...
fords4life Posted December 8, 2019 Author Share Posted December 8, 2019 So, if you want the 130A you should get the 8.25" If you want the 95A I think you could use the 7"C-C. Jim - If the plug was the issue and the plug is gone, is there really a need to replace if it’s working properly? Looks like there are 7” 130a versions if I’m looking correctly. Any advantage to the larger frame for the same amperage? Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 8, 2019 Share Posted December 8, 2019 Jim - If the plug was the issue and the plug is gone, is there really a need to replace if it’s working properly? Looks like there are 7” 130a versions if I’m looking correctly. Any advantage to the larger frame for the same amperage? Hopefully not. Alternator rebuilders resorted to hardwiring them because too many people did not follow the TSB and replace the plug every time any component of the charging system was serviced. Then they would try to say the alternator was no good, even though it was the fault of the trucks harness. First, there are several issues with the 2G. Plug contacts get wet and corrode, leading to heat, which leads to more resistance and corrosion, which makes for more heat, which leads to....... Second, that heat causes the plug to melt, whereupon the alternator output goes directly to ground of the case. Which causes the regulator to step up the output, and (if you're lucky) the diode board (rectifier) to have a meltdown. Third, as Gary pointed out, the sense wire is on the other side of the fusible link. So, if for some reason the fusible link goes open, the alternator goes full field with nowhere for that charge to go. Fourth, the decision to use a plug dictated the use of TWO 10Ga. wires, because you can't really plug in a 60A 4 or 6Ga. cable and have a secure enough connection to pass that juice. These Bk/Or wires then splice together into a fusible link, and that goes to the trucks main harness. It's a patch on a patch on a patch in order to meet a mandate from Dearborn to make the alternator connections quicker and more foolproof. There are 7" 130A 3G's. I sent one to Gary for Big Blue. But if you have the 7"C-C mount and the 148 mm diameter 130A case you won't be able to swing it very far to adjust it (if you can get the pivot bolt in in the first place) Link to comment Share on other sites More sharing options...
Danny G Posted December 10, 2019 Share Posted December 10, 2019 Jim - Thanks. I missed this. And it has taken me a long time to get my head around it. Operative word is "has" as I'm not sure it is in the past tense. In any event, we do have two Lester #'s posted here: Documentation/Electrical/3G Conversion and on the Choosing An Alternator tab. But if you have more please post them here and I'll get them included. (And if you already have and I've missed that then I'm sorry.) This may help with the list: https://alternatorparts.com/ford-type-3g-4g-6g-series-high-output-alternators.html Link to comment Share on other sites More sharing options...
fords4life Posted December 10, 2019 Author Share Posted December 10, 2019 This may help with the list: https://alternatorparts.com/ford-type-3g-4g-6g-series-high-output-alternators.html That is a holy grail right there. That's what I've been trying to find with no luck. Thank you! Link to comment Share on other sites More sharing options...
Gary Lewis Posted December 10, 2019 Share Posted December 10, 2019 This may help with the list: https://alternatorparts.com/ford-type-3g-4g-6g-series-high-output-alternators.html That is a holy grail right there. That's what I've been trying to find with no luck. Thank you! Yes, that's a good find. I've added that info to the bottom of the Choosing An Alternator tab here: Documentation/Electrical/3G Swap. I think we (I?) need to clean that tab up, but wanted to see what y'all thought about it first. As you'll see, it appears to me that there are only three alternators in that list that are appropriate for our swaps. So I only added those to our page. Thoughts? Link to comment Share on other sites More sharing options...
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