Voltage not steady, drops at night when lights are on,code 36 culprit?

[Franko914]

no, im pretty sure that the full 105 amps is at approx 5000 rpms. if i remember right, normal driving we only see around 60-80 amps due to the low speed of the diesels

Pieces of my engine would be all over my neighbourhood at that rpm level, then again, you must be referring to the alternator rpm...

 

[Franko914]

Ok I think I got it fixed. The wire coming from the alternator was only 10awg, so I replaced it with a 4awg, and when doing so found the allternator post was loose. So I took that off and took it apart, and cleaned up the contact points on the spindle, and tightened up the nut to the alternator post, that you can only get to by taking apart the alternator . Test drove the truck , and am showing 14.06V with the headlights and radio on. Oh yeah, this is also the original alternator, 105amp Delco Remy, so I dont think 14.06V is too bad. I am going to add another 4awg wire going to the passnger side batt just for extra current, and will be replacing the
alternator with a high output model, SS diesel has one thats 120amp for $99.95, and AlternatorParts.com has two versions 140amp for $159.99 and a 170 amp for $199.99, any thoughts, should the 120amp be sufficient?

Glad to hear you're working out your issue. That's a great idea running another 4 ga wire from the alternator to the other battery. If one alt-batt connection ever goes bad, there will be another connection already in place (redundancy)... unless it's the connection at the alternator. Thank you, methinks will do the same.

Do the battery post modification Matt mentioned. Less, if any, headaches down the road with the battery cable connections.

 

[1995yukon65]

No, from what i have read thats engine rpm. The alternator was made for the gassers and the pulley was just changed out for the diesels. Again thats just what i have gathered from multiple things i have read so dont hold me to that

 

[Frostydevil]

Not to hijack a thread, but has anyone used a battery isolator in the system to curtail the problem of a weaker battery drawing from the other?

 

[handcannon]

I have never seen an isolator big enough to handle the draw through it that would be needed. The ones I have worked with are sized to only handle small draw items,not up to starter sized items. If there is one big enough it would most likely cost as much as, or more than a pair of new batteries.

Don