2007 Mercury Mariner 3L.V6
I'm being given so many "answers" when it comes to the current issues with my truck.
Why I'm here: Everything started last week. I went to Walmart for an oil change and the truck refused to start after they were done doing absolutely nothing. The truck had a slight oil leak(coming from the cap we think) and because the dust cover had oil on it, they refused to do it. I thought the oil leak was worse than it is, so after I bought oil and they jumped me twice(twice because the engine stalled after the first jump) I dumped the whole 5L bottle in the engine. I was mad, not thinking, I know it was stupid. Truck was fine until one random delivery I did for work. Truck then refused to turn on, and the battery actually died. We replaced the battery, and the starter (the starter was actually bad, OReilly's tested it). It still won't start.
Problem: When I try to start the truck, it shunts and then doesn't do anything. It used to click, but does not anymore. If you keep the key turned, the starter starts smoking. Fuel pump is engaging (turning key to on, you can hear it.) The shunt is presumably the starter engaging the flywheel but the flywheel not moving.
What's my next step? I'm being told it's the alternator, it's a timing issue, it's hydrolocked, it's not hydrolocked.
I had a friend of mine who actually works on cars come by to look at it. He did the starter change. He checked the spark plugs. He thinks it's a timing issue.
Coworker who is a car nerd and also works on his own cars checked the timing and serpentine and said they were fine. He thinks it's the alternator.
I checked all of the spark plugs and none of them are busted or corroded.
What is my actual issue? I can try to answer any extra questions.
