MAC5200 Low Pressure

[NcFramer]

i have a makita 5200 air compressor. i use daily for construction. the unit has been building water/moister in tank for a while now getting more and more. and today it wont pump past 80lbs and just keeps running has bad smell from water in tank. i cant really hear a leak.
would anyone know what it may be and what part/parts i need to fix it?

edit: when i shut it down it has a rattling noise at fan/motor

[Mike]

Well, the smell from the tank is a concern but it shouldn't affect the pressure in the tank. I'm wondering if the piston and rings are going bad, That would explain the poor compression. If oil is getting past the piston ring that could explain the bad smell. Also if your air filter is clogged, it will cause oil to be pulled past the piston rings into the tank. I would definitely check the filter and if it's clean, you're going to have to look at the piston. Here's a link to the Makita MAC5200 parts breakdown for reference:

Makita MAC5200 Air Compressor Parts : eReplacementparts.com