How far to tighten barbs?

How far down do you tighten the barbs on a MCR220 radiator? I can tighten them down about halfway by hand. Do you use a wrench to tighten them all the way down? The Apogee has Orings so they must be tightened all the way but the rad doesn't, just plastic barbs. Also, do you take the blocks apart and clean them and the rad before use?

I just started working on my first set with the same rad. I made the mistake of tightening them down to where they were flush with the surface of the rad using a wrench. this made the thread section of the nylon barb start to crack and seprate from the barbed part. I would definitely recommend using teflon tape, and then tightening them with a wrench almost all the way down. Maybe 90% if you want to think of a percentage. I remember seeing a post about someone taking apart their apogee and cleaning out some bits of metal. It's a good idea as long as you put it back together properly, but I don't think it is necessary.

You should tighten them all the way to decrease the chances of leaking, just dont force it tight. As far as cleaning the blocks, it's really up to you.

What about cleaning the rad?

I put a bit of Dow 33 on the threads to ease friction so I could get the O-ring to seat completely. You could use Dow 55 if you'd like the O-ring to swell although that's a little harder to get.

you can try liquid teflon - I like it better then teflon tape and it looks cleaner when it settles and dries. for those nylon barbs tighten it hand tight then go 1/4 to 1/2 turn. They're 3/8" or 1/2" NPT most likely. Certain nylon barbs are weaker than others, ie the white barbs at home depot are as opposed to my PushOn barbs I got from McMaster.

It is always a good idea to rinse things out before using as bits and pieces can easily end up in the product before you receive it.