upgraded alternator installed - 250A (1 Viewer)
- Thread starter James Bentley
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
My 250amp still works great four years later with 3k+ watts of stereo, two agm batteries snd I don’t really drive it a ton.
Great to know!
How did you wire the positive lead from the alternator to the battery? Did you wire it directly to the positive battery terminal, or did you still wire it to the fusible link block hanging off the side of the battery?
Did alt to battery snd kept standard alt to fuse block wire. Didn’t want to mess with that thing
Just to clarify, are you saying that you're only running the original wire, or do you have a heavier gauge wire running alongside the original?
Going through the fusible link, did you need to upgrade that to a higher amperage so you don't blow it?
Heavier gauge wire…2/0 welding…big 4
TRDdrew
SILVER Star
- Joined
- Mar 14, 2019
- Threads
- 31
- Messages
- 1,134
- Location
- Southern Maryland
- Website
- www.capitallandcruiserclub.org
I was taking a look at their inventory, it looks like they have a 220a for 99-02 and the they list a 120a for a 98 LC. Someone correct me if I'm incorrect but I was under the impression that 98 -00 used the same 3 pin connector alt. A 120a would still be an upgrade over my stock 80a in my 98 but I do run a dual battery set up and I would love to get as much power as I can. I was wheeling over the weekend and I noticed sometimes at idle the truck would drop down to 12.6V and would come back up to about 13.2 when I started moving again (of course the a/c was running the whole time as well). All and all everything was fine but makes me think that the OEM unit might be on its way out.
James Bentley
SILVER Star
- Thread starter
- #28
Hi @xplore and @Biga27110
The alternator has been perfect, no issues.
My 100 is not a DD and I haven't had any water crossings that might contribute to premature wear.
(Thinking that not running it submerged = greater life expectancy for the alternator...YMMV)
(Plus I want to install my snorkel and extend my breathers before I hit any water crossings!)
I did run the additional cable directly to the "fuse block" or tab that hangs off the side of the battery cable.
A few black zip ties to secure it and it all blends in, looks stock or at least doesn't stand out.
It is run along the high pressure A/C hard line.
The 2 gauge cable has a thick insulation jacket and does not rub/contact any sharp edges along its route.
I also used about 1 foot of heat protective sleeve where the cable connects to the alternator.
(Thinking they have a heat shield on the alternator for a reason, might as well protect the additional cable I am running with something too)
Let me know if you have other questions!
(This nighttime pic of my engine bay is brought to you courtesy of my under hood rock lights on a plunger/pin switch with manual override switch)
Thanks for the update @James Bentley!
I installed the new alternator yesterday and ran heavier gauge wire along the same route you did to the battery. I still need to upgrade the ground wires and finish up some other little things, but hopefully that will be wrapped up this evening.
I did some research on the fusible link for the alternator, and I'm going to bypass the original one. I purchased this from Amazon last night, so this will be the only thing between the alternator and the battery terminal.
Amazon product ASIN B07R99N5MZ
I installed the new alternator yesterday and ran heavier gauge wire along the same route you did to the battery. I still need to upgrade the ground wires and finish up some other little things, but hopefully that will be wrapped up this evening.
I did some research on the fusible link for the alternator, and I'm going to bypass the original one. I purchased this from Amazon last night, so this will be the only thing between the alternator and the battery terminal.
Amazon product ASIN B07R99N5MZ
I was under the impression that the 98-02 were all the same size and plug type. I just did a quick search and confirmed that alternators on Amazon are showing as compatible between that entire year range, so you should be good. Perhaps they just had a lower amperage version for that year since the original was lower.
Those work well for high amperage car audio application so shouldn’t be any different.
I got my 220a alternator installed and wired into my LX. I still need to clean up some wire routing and replace the battery terminals before I can call this finished, but you can see the 250a fuse I installed off the side of the battery for the new alternator cable. With the new alternator, I measured 14.3ish volts at the battery when idling instead of the high 12 to low 13 volt range that I used to see.
I know that a lot of people double up the alternator cables and mount the old positive lead right on top of their new heavy gauge one, but I didn't do that. The ring terminal on the old cable was too small to fit the new alternator, and I didn't want to bother putting a new connector on. I used 1/0 cable, and that will be more than enough. The only other difference from OEM is that there's no place to mount the bracket off the side of the alternator to hold the wire harness, but that's no big deal.
When the new electric fan kicks in and the alternator steps up its output, I experience a momentary dip in RPM that is noticeable, but it's not bad and the idle up kicks in a moment later. It seems to hit hard when it engages, and I wonder if that's because of the smaller pulley on the alternator.
We'll see how it does long-term, but so far I'm really happy I made the upgrade.
I know that a lot of people double up the alternator cables and mount the old positive lead right on top of their new heavy gauge one, but I didn't do that. The ring terminal on the old cable was too small to fit the new alternator, and I didn't want to bother putting a new connector on. I used 1/0 cable, and that will be more than enough. The only other difference from OEM is that there's no place to mount the bracket off the side of the alternator to hold the wire harness, but that's no big deal.
When the new electric fan kicks in and the alternator steps up its output, I experience a momentary dip in RPM that is noticeable, but it's not bad and the idle up kicks in a moment later. It seems to hit hard when it engages, and I wonder if that's because of the smaller pulley on the alternator.
We'll see how it does long-term, but so far I'm really happy I made the upgrade.
YezusLX
SILVER Star
I need to revive this yet again. I am about to install the BNR 220A in my '99. I have the big 3 cables and fuse block on the way but I was told by BNR I needed a new belt. So, I ordered an OEM belt and picked it up. I missed that when they told me I needed a new belt and that I would need a one-size smaller belt. Does anyone have a clue what that belt size is or a part number so I can swap out my new OEM belt or is it possible to run the OEM belt with a BNR alternator?
The pulley is smaller, but it worked just fine for me with the OEM belt.
Just a heads up though, one of the bearings ended up failing for me after about 9 months. I ended up putting the original alternator back in to get a warranty replacement. Hopefully, the second one does better when I put it in. I'd be curious to hear other people's experiences with these alternators to see if there are any other early failures.
YezusLX
SILVER Star
This is interesting. What were your early warning signs? Could this be attributed to the belt size?
It had nothing to do with the belt size. The warning sign was the audible sound of a failing bearing when the engine was running. I only noticed the sound when the windows were open, so I think I caught it early before it got much worse.
TreatSmash
SILVER Star
I just did this job and used a 2225 mm belt instead of the factory 2240 belt. It works great. Also be advised on the 100 series the Big 3 upgrade is actually a Big 5 upgrade.
I already filmed a video, I'm getting ready to upload to YouTube this weekend covering the locations of all of the cables and how I upgraded them.
YezusLX
SILVER Star
This would be awesome! Thank you. Would you happen to know a ballpark on the length of wires? I think I am going to make my own.
TreatSmash
SILVER Star
While
Sitting here at Buffalo wild wings watching UFC, from memory I would say conservatively 15 ft of black and 8 ft of red will work
