I don't understand how voltage could drop at the battery posts unless the battery was bad. That just doesn't make sense.

 

I agree if he's checking from post to post and the voltage drops to next to nothing( load test), she's shot.

 

Just because your battery tester is a snap on doesn't mean its jesus in a box. You got an old Sun VAT-40 layin around? Use one of them. OPINION: those are some of the best battery testers available. I don't trust those new hocus pocus machines. The old sun vat units will actually put A LOAD on the battery when they LOAD test the battery. Makes sense to test it this way IMHO

As for it doing it with your known good (good job, swapping in known good parts) battery, we need to know smore specific details. Did you check your voltage drop of your cables yet? It sounds like you have a voltage drop somewhere in there. You should have less than .2V from the block to the negative post, less than .2V to the starter relay.

Check voltage at your switched ignition accessory circuit and your hot at all time accessory circuit as well. These are "past" the ignition switch.

 

I would agree, I had a battery that one of the newer electronic machines insisted was bad and I had an old manual charger so I charged it overnight and continued to use it for several years without issue.

 

well the battery being shot would make sense, but i would think by boat battery would at least do something even if its only got 550 cca. i havent had a chance to put the multimeter on the boat battery though. but my cables and solenoid are ancient anyway so i just went ahead and ordered some nice OFC 4ga and gold plated wire lugs and battery terminals to replace the old crusty stuff. and ordered a new solenoid from rock auto.

ill put the multimeter on the boat battery tomorrow and see what it does

 

Voltage without Amps = nadda! Quote: "battery terminals to replace the old crusty stuff" Bad cables is my guess.

 

yeahh ive got some nice wire and lugs to make new cables coming in too

 

Use felt washers beneath the terminals and smear everything with dielectric grease when you put the new stuff in. It will prevent corrosion from happening. Whether or not the corrosion is the source of your problems, its certainly not helping anything.

 

true that. would i be able to find those pads at advance?

 

Yep, and dielectric grease as well.

 

haha i got a ton of that in my toolbox from when i was always hooking up car audio systems

 

Have you checked for voltage at the solenoid from the ignition switch? Do all of your accesories function in the acc position? Do the guages function in the ON position? I think your problem would be solved with proper troublshooting of your starter solenoid. Hope this helps.

 

new solenoid is in the mail. it was like 10 bucks and i didnt feel like going through the trouble since its ancient and my starter is brand new anyway.

I did take my ground off the block and wire brush the hell outta the wire lug and the bolt hole area, it helped significantly. my lights at least came on dimly now.

But i think my battery is fried as well. this was just a whole slew of ***** that hit the fan all at once: old starter shorting inside and draining the battery to nothing repetitively, solenoid started smoking while I was trying to jump it to test the starter directly, and wires and connections are old as hell.

 

A bad battery can cause a lot of electrical problems. The alternator will go nuts trying to keep it charged, and lots of accessories don't work right when they are underpowered. The starter, for instance, when voltage drops, it tries to pull additional amps, which puts more of a strain on things like the solenoid.

 

hmmm I wonder if that had anything to do with my headlights pulsing when the trucks running....

I put the boat battery in last night with the multimeter, and the voltage drop isnt quite as bad as my other battery even though its only 550ca compared to 1000ca. managed to get it running for a second when it was hooked up to jumper cables, but after that, i couldnt get enough power to engage the starter