I have a 2016 4runner with a Magnuson. The SC Belt chewed a hole in my drivers side AC line after about 500 miles. I will zip tie it out of the way after I replace it.

I got a qoute for a local shop, it was around $800 to replace the line ~200 parts and $600 labor, so I thought I would give it a try.

I have the guages and compressor coming, and have watched a few youtube videos. My big question is how do I make sure that I have enought oil in the AC system without taking the compressor off.

There is oily residue on the skid plate at the bottom of the engine bay, so I am sure I need to add some, just dont want to over/under fill.

Anyone have good advice or approach to the problem?

Do you have a vacuum to evacuate the system? I thought that was part of the procedure when replacing any part of the A/C system.

Your oil level will be fine, don't mess with it.

Replace the line, then use standard gauges and a vacuum pump to draw vacuum on the system for a while, then turn off and wait to see if any leaks. If not, recharge and you should be good to go.

Depending on how long it’s been open to atmosphere, I’d get a new dryer.

You cannot, only way is to drain and flush system and then fill to spec.

Usually all hoses and tubes hold 1oz and the accumulator holds 1oz
It is advisable as mentioned to replace the accumulator when a system is opened up.
Replacing accumulator and the hose personally I would replace with 1.25oz of oil
Be sure to pump down to 500 microns to rid the system of any moisture.

I do have a vaccume pump.