L4 Waterproofness? (With O-ring)

I know that the L4 isn't very waterproof without the o-ring, but how does it do underwater with the o-ring? How deep can it go with out leaking, and can you turn it on and off underwater? /ubbthreads/images/graemlins/confused.gif

Assume that all the o-rings are present, and that they are all well lubed.

I know somebody knows the answer to this. /ubbthreads/images/graemlins/icon23.gif

Well my L4 arrived today! /ubbthreads/images/graemlins/smile.gif

My L4 has the o-ring, that was forgotten on many peoples'.

I did a blow test for the KL4 end, blowing into the bottom of the light without the Z57 on and of course without the batteries. No bubbles at all. At this point I had not lubed up anything so I was pretty impressed.

I took off my KL4 and put the Z57 clickie back on. I blew hard, and I got a few bubbles! /ubbthreads/images/graemlins/thumbsdown.gif

I lubed up the threads between the body of the L4 and the clickie. I did the blow test again, and got one bubble. It seems that one bubble sealed it up, because after that I didn't get any bubbles. I tried blowing for a while, but no bubbles.

I am still not sure what to think. I got a top-quality light from a very reputable company (Surefire), yet the light didn't come very waterproof. Even with all of the o-rings, and lubing them up, I am not sure how waterproof the L4 is. /ubbthreads/images/graemlins/jpshakehead.gif I am not taking many chances with it, because it was so expensive. The L4 will be my EDC, and I wish I knew for sure that it is waterproof or not. /ubbthreads/images/graemlins/crazy.gif /ubbthreads/images/graemlins/icon23.gif

Yea, Aaron. I have the same concerns. Here's what I've decided to do with my high-end (meaning high-priced EDC. I going to use them the way they're supposed to be used. If they get bang up or dropped in a puddle or fall into the lake, I'm going to trust they perform as advertised or at least close to that. If not, they go back for a replacement. It's simple as that. I tired of wasting time and energy worrying as to whether or not such-and-such a light will hold up to what I consider normal usage. To me, dropping a light in a puddle constitutes normal usage and should not yield water in the light or moisture/condesation on the inside of the lens.

What exactly does Surefire say about the L4 and waterproofness?

I know they have a "If it breaks, we fix it!" guarantee but would that cover replacing the L4 if damaged by water?

In most real world cases, the light will leak if it is not water proof in an equalized (rain) or positive ambient pressure state (under water). The blow test is not really valid for either of these conditions. I for one have no idea how "water proof" the L4 is in practice or is designed in theory to be. I have seen or heard no stated claims. Having flooded my share of UW equipment due to foreign objects contaminating otherwise appropriate seals I know that even if the *design* is sound, the onus is still on me.

If as you say, someone has the answer to this, I too hope they share it here.

- Don

the light shouldn't leak from the tail...as far as i know surefire has had problems sealing their bezels, but their tailcaps have never leaked on me. try cleaning and lubing the O-ring, and don't overlube /ubbthreads/images/graemlins/smile.gif