Charging/Starting System Issues

The other weekend my truck went swimming. See mid recovery photo attached. However, since then I have been having issues starting the truck. Usually, requires 1-3 tries to start if a jump is not required. Does any one have suggestions on what I should check next?

So far I have done the following:

1. Checked the Battery - Bench test with multimeter at 12.6 V.
2. Check battery with truck running - 13.6 V
3. Checked the Starter - SAT truck starts when jumped.
4. Assumption at this point was a bad alternator
5. Alternator was replaced with Toyota original part for the truck.
   
6. After alternator was replaced started truck and check battery again still only seeing 13.6 V
7. I have check all the fuses in the system and made sure that all additions (winch and lights) were off and not drawing power. Still at 13.6 V
8. With everything running still only getting 13.5 V at the battery

 

Oem battery?

 

I had that problem a few years ago after some muddy off roading. I took it to the dealership and they changed the battery but that didn’t fix it. After a few days the problem went away and hasn’t happened since. I came to the conclusion that maybe the starter/ solenoid got wet. It seems that it just needed to dry out.

 

I haven't had a reason to measure voltage on my third gen yet but is 13.6v not normal for this engine when idling? That's always been pretty much the standard voltage for a 12v system to read with a functioning alternator.

 

So are you saying it starts first try every time with a jump?

 

check your starter to see if its completely gunked up
Like the other poster said check and see if the start solenoid isn't blocked or something

Also swap a battery with a friend to see if it fixes it

 

Yea its the OEM battery.

 

Yeah it will Start with a jump and there was no change when I started using a friends battery.

 

sounds like something is drawing more current than a single battery can deliver

makes me think that some electrical motor or solenoid is gunked up

can you post a video of it trying to start?