Broken Surefire!?!!

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Gitlaa

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Jan 3, 2007
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There is something seriously wrong with my surefire g2. When i tighten the tailcap all the way it does not power on even with fresh batteries, I checked the lamp and it works perfectly, then i checked the tailcap on my c2 and that works perfectly as well. When i put a different tailcap on my g2 it powers on way before i could twist the cap all the way on. So it must be the body?? how is that even possible?

Here is a short video http://www.youtube.com/watch?v=1ffJc-kR20A
 
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Why would you suspect the body? Didnt you say yourself switching the TC out fixed the problem? The body on a G2 isnt made of a conductive material I dont see how that could cause your issue.
 
I said the g2 tailcap works on my c2, therefore proving that it isn't the tailcap.
 
Try removing the tailcap from the G2. Use known-good cells and a known-good lamp into the light. Then touch one end of a wire to the Neg (-) terminal of the bottom cell and the other end of the wire to the exposed metal sleeve of the G2's body tube. That should complete the circuit. Does the light go on? If not, then something is wrong with the lamp connection to the metal sleeve. If it does go on, then the problem is the tailcap (which doesn't seem like it will be the case since it worked in your C2).

For the former problem, re-attach the tailcap.

Turn over the light and remove the bezel to expose the lamp. Screw down the tailcap all the way (your test of the tailcap on a C2 shows that the tailcap is known-good) and then press the lamp down into the neck of the light. Does the light come on? If not (assuming a known-good lamp), then the springs aren't making electrical connection to the metal sleeve that is pressed into the plastic G2 body. You can try to verify this by using some hookup wire to connect the lamp's center spring to the top center terminal of the battery and the large outer spring to the metal sleeve. That should complete the circuit and the lamp should light. If the lamp lights, then you can try stretching the springs for both the lamp and the tailcap. It could be that there is some tolerance stacking going on and things are coming up just a bit short to make a complete circuit. Also make sure all contacts are clean.
 
I said the g2 tailcap works on my c2, therefore proving that it isn't the tailcap.

Ohh my appologies. When you said you checked the TC on your C2 I thought you meant that you checked your G2 using the C2 TC. What do the threads and endof the battery tube look like on your G2. Did you try putting the C2 TC on the G2?
 
There's not a whole lot that can go wrong with these units. I would be suspect of the connection between the lamp assembly and the top of the battery tube. Inside the G2 I believe IIRC is a thin metal sleeve. In order to complete a circuit the negative side of the battery has to touch the tailcap which touches the metal sleeve which touches the lamp which touched the positive battery nub.
 
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to make this more simple to understand. If i use the g2 batteries with the g2 head and the g2 tailcap in my c2 body then it works just fine. when i put that on the g2 body it refuses to fire up. also if i put my c2 tailcap on the g2 it turns on way too soon. its crazy, maybe the video will help
http://www.youtube.com/watch?v=1ffJc-kR20A
 
Now if only everybody that broke something posted videos that in depth! I really dont know what to tell you? Maybe Email surefire and send them the link to the youtube vid although im sure somebody here will be able to answer your question sooner or later.
 
When i put a different tailcap on my g2 it powers on way before i could twist the cap all the way on.

your tailcap's spring must be veered to one side, thereby shorting the battery to the side on contact rather than after been screwed down to a certain point. if not then the base of the spring is somehow shorting it out. theres absolutely nothing in the G2 tailcap that could have been broken...save the rubber boot that I know of
 
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your tailcap's spring must be veered to one side, thereby shorting the battery to the side on contact rather than after been screwed down to a certain point.

that would make sense, but why would both the tailcaps work just fine on my c2 body?? watch the video maybe it will help. also the springs on both tailcaps are perfectly centered.
 
hmm :thinking:

tried wiping all the lube off the tail end of the body then try?
occiasionally if theres a film of lube on the end contact pad there may be intermittent contact, if not then I'm out of ideas:green:
 
when you use the C2's metal tail on the G2, it's normal for the light to turn on like that. I even verified with the tail from my Z3 on my G2.


I'd clean the tail end of the G2's metal sleeve really well with a scotch brite pad and use a Q tip with rubbing alcohol to clean out the insides of the tailcap, mainly between the plunger and the threads. There is a centering Oring in there too, make sure that's in place. If you look close you can see it on the plunger.
 
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to make this more simple to understand. If i use the g2 batteries with the g2 head and the g2 tailcap in my c2 body then it works just fine. when i put that on the g2 body it refuses to fire up. also if i put my c2 tailcap on the g2 it turns on way too soon. its crazy, maybe the video will help
http://www.youtube.com/watch?v=1ffJc-kR20A

So all components (metal tube sleeve, tailcap switch, lampassembly) work, just not together. Sounds like tolerance stacking to me. Is the sleeve too far back toward the tail end of the tube such that it engages the C2 switch early and doesn't engage the P60 lamp assembly outer spring at all? Try stretching the G2 tailcap's tail spring and inserting a paper clip bent into a circle into the flashlight neck to help create contact between the sleeve and LA outer spring.
 
So all components (metal tube sleeve, tailcap switch, lampassembly) work, just not together. Sounds like tolerance stacking to me. Is the sleeve too far back toward the tail end of the tube such that it engages the C2 switch early and doesn't engage the P60 lamp assembly outer spring at all? Try stretching the G2 tailcap's tail spring and inserting a paper clip bent into a circle into the flashlight neck to help create contact between the sleeve and LA outer spring.
Good suggestion, my first (& only) thought was the positioning of the press-in metal sleeve inside the nitrolon body.
 
I tried all of the suggestions but it still does not work. Should i send this one back?
 
Could you bring the G2 to one of the Surefire retailer near your area and try with their G2 body and tailcap? Perhaps then you can convince Surefire to send you a new body or tailcap without you sending back yours. my .02 lumens. :grin2:
 
In your video, the G2 has a 6P metal bezel. The C2 appears to use an LED drop-in, not the P60 that is apparently in your G2. Any other differences, such as different batteries?

Try to keep things as constant as possible for your tests.

Where is the presumably original G2 Nitrolon bezel?

Can you provide photos of the C2 and G2 tailcaps, viewing the inside of them (spring side, not button side)? Also, the lamp assemblies (side views to compare overall lengths and spring geometries), the tops and bottoms of the C2 and G2 tubes (tail and neck), overall lengths of the tubes (shown preferably side-by-side), and C2 vs G2 batteries.
 

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