You go buy look. A 2nd person is handy for this. I had a buddy turn the crank till I saw the valves close and then he gave it an addl 1/4 turn To make sure. You have some time between open/close, so no worries. Just don't try doing more than 1 port at a time and you'll be fine.I found a way to access them. How do you know what position the valve is in? Or do you just go until it looks to be closed.
I don't see this being a huge issue until your car gets some mileage on it. I has 70k or so, mostly highway. If you do a lot of city driving, maybe around 50k. I fire its something I'll do 4 times throughout my ownership, based on 200k miles. I keep my cars for a while, lol.
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