I have a fire pit and when attempting to light it with the internal proprane valve; it will light, but when I quit depressing the valve, it eventually burns itself out.

I find that the trigger valves in these guns are reliable and that most problems with random fire is lack of lubrication and adjustment of the safety foot. Assuming that air does not leak when you connect air supply and leaks from trigger when attempting to fire. This indicates a lack of lubrication of the head valve. Remove the head valve and lube with white grease.
Test the gun, of ok then you are done. If no joy, then check safety foot for adjustment. How to test if the safety foot is the problem.
Remove the nails, remove the trigger leaving exposed the trigger firing pin. Adjust air supply to 100 psi and connect to gun.
Assuming no leaks quickly depress the trigger valve pin all the way in. If the gun fires then the problem is with the safety foot and or the actual trigger is not pushing the firing pin all the way in when attempting to fire. Make adjustments accordingly. Good luck with your repair.

Air leaking from trigger when attempting to fire the gun is normal and should cause nailer to fire, however if the trigger pin is not depressed all the way in,the gun may not respond. Easy test. Remove the nails and remove the trigger. Connect the gun to air and quickly depress the valve pin all the way in with finger. If the gun fires, adjust the safety foot so that the trigger pin is depressed all the way in. If the gun still does not fire, then remove the head cap and pull out the headvalve. Apply plenty of white grease to orings and retest. If the gun fires, then replace the headvalve orings. When the headvalve orings are worn, air will leak from bulkhead chamber to the headvalve chamber causing the gun to not respond to the trigger. The addition of grease to worn orings will make them temporarily seal. Good luck

Most likely stuck trigger valve. Easy to check. Remove nails, remove trigger to expose the firing pin of trigger valve. Connect air and very quickly depress the firing pin all the way in. If the gun fires , adjust the safety to depress the trigger valve completely. If the gun does not fire, replace firing valve, or remove and check /lube o-rings in valve. Good luck

tank safety valve. turn it off, turn it on several times with burner off.
if you hear a definate little snap,, thats when it activates the internal safety cutoff valve. when you get the valve on without the snap your good to go. I have had some bottles that I had to jar the bottom of bottle on the ground to get the valve to drop and to give out the gas. Then when all else fails take it back. always keep it upright..

Could be just a lack of lubrication in the headvalve /orings or the safety foot is not pushing in the trigger pin all the way. Easy to check. Remove the head and pull out the head-valve. Apply plenty of white grease or silicone paste to the orings and the surface where the orings make contact. Install the head and test. If the gun fires then you are done. If the gun does not fire, make sure that the safety foot is depressing the trigger valve all the way in when attempting to nail. Simple test is to remove the trigger exposing the firing pin. With nails removed and air connected, with quick motion depress the firing pin all the way in. If the gun fires make adjustments to safety foot. If the gun still does not fire (with headvalve lubed) replace the firing valve core part # ca0108. Good luck

Take a look on amazon for it: Amazon com dewalt trigger valve I hope this was helpful. Have a nice day

Not much information on the problem or what you have tryed to do to fix it, but my first guess would be a pitted petcock valve. If the gas ON/OFF valve gets pitted then the gas simply will not shut off fully.

Take the tank back off and open all the valves on the cooker. Close all the valves on the cooker. Put the tank back on the cooker. Open the tank just barely. Light the burners. The valve cannot be turned wide open on the newer grills.

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