Dewalt Round Head Framing Nailer D51845 - Answered Questions & Fixed issues

The bulkhead on a nailer is the part that separates the pressure chamber from the lower compartment of the nailer. Usually round center hole for the cylinder to pass thru. The outer shape conforms to the inner contour of the body. Usually made of plastic some are metal and have orings seals or oring surface.

Dewalt uses a combination buna and vinyl orings. The vinyl orings in their nailers fail by turning into putty. To fix your problem replace the trigger valve or the vinyl orings within. You will meed three orings in the trigger valve, (buna 70) , two rings are 2mm and one is 6mm. Within the body of the gun there are 5 more vinyl orings that fail. The rebuild kit has some vinyl orings and will most likely fail also. Convert to buna for longer life. Good luck

Use an Allen wrench to loosen the two or 4 bolts on nose of the gun. Take the plate off and remove offending nail.

Parts and manual can be found here: http://servicenet.dewalt.com/ Good luck with your nailing projects

Where does the air leak out from? If it leaks from the trigger DeWalt makes a trigger valve assembly part # 641006-00 list 8.89 BUT if it leaks from other areas we have to look into it deeper. If it is just the trigger valve let me know and I will give you instructions how to remove and install the new one.

Check this notice and post your question again if you nailer is not part of this recall. Good luck. D51844 & D51845 Recall Notice Published 06/09/2005 08:49 AM ' Updated 09/29/2011 09:35 AM What is the recall on the D51844 and D51845 about? The contact trip on some of the nailers may not operate properly, which may permit a nail to be ejected with only trigger actuation.Only nailers with the following date codes are affected:200203, 200204, 200217, 200302, 200304, 200308, 200315, 200325, 200329, 200343, 200403, 200404, 200406, 200407, 200412, 200413, 200415, 200416, 200417 See the link listed below for illustrations & more information regarding the recall.http://www.dewalt.com/us/articles/article.asp?ID=1373

Piston oring will not cause gun to leak. Most likely the orings between the cylinder and cylinder spacer and orings sealing the cylinder spacer to the body. The cylinder spacer is the white plastic piece visable when you pull off the head. Order the oring kit and replace all the orings in the lower part of the gun. Dewalt used some vinyl orings on the cylinder that failed. The trigger also has orings that will fail. Good idea to order a trigger valve and have it ready( or replace now if the gun is several years old). Good luck and post again if you have question about this gun.

Time for oring kit # d518005 available at Dewalt service center or at www.toolpartsdirect.com.
May as well order the replacement trigger valve while there. These two items will renew your gun. Good luck

Dewalt framing nailers have several orings made of urethane that lose their capacity to seal over time (gun being used or in storage, orings will fail). Too much or too little oil would not have made much of a difference. If your nailer is a couple or years old, order oring kit and replace the orings that seal the cylinder to cylinder spacer(white plastic between cylinder and body of gun). In the head if the gun there is a stationary headvalve that usually does not fail. On some nailers, too much oil will cause the orings to swell and lock-up(but not leak air). Good luck

Dewalt has two triggers available for their framing nailer. The black trigger (390746-00) is a bump style trigger. While holding the trigger, you will be able to fire a nail by pressing nose against work. This trigger is preferred by most framers because it is much faster. Gray trigger will only allow one nail to be fired. Bumping will not work with the gray trigger. With trigger released, you must place the nose against work then pull trigger to fire. To fire next round, you must release trigger, pull gun off the work, again place nose against work then press trigger. Check dewalt web site for recall information. Some dewalt framers have been recalled for faulty trigger. Good luck with your projects.

Dewalt has a new trigger valve to replace the original (part number 5140095-73). Not sure if the new valve is replacement to address an issue or natural progression. I would also replace the orings that make contact with the reference #55 on parts list called the bulkhead. There are four orings contacting the bulkhead that wear and may contribute to multi-fire or miss. Finally, look for worn parts that contact the trigger. The safety foot pushes up on the inner part of trigger then pushes on the firing valve pin. If safety mech parts are worn or trigger is worn, the gun may miss. Parts are at dewalt service center or at www.toolpartsdirect.com Good luck

Take a screw drive and push down on the hammer it is sturck.

Have you looked into the recall for D51845? Here is the link:

http://support.dewalt.com/app/answers/detail/a_id/1137/~/d51844-%26-d51845-recall-notice

Maybe you will not have to repair it yourself. Good holiday

I'm not sure what you mean by "breaks the last 3-4 nails from the end' but because of the damage that can be done by firing an empty nail gun most manufacturers are making their guns stop working when the magazine gets down to the last three nails. You would need to check your operators manual to see if your model is one of these.

Spray wd40 on the nail track and oil gun well. if that doesn't work you have a bad push pin in the gun will have to replace

http://servicenet.dewalt.com/

There are 4 types of D51845, and your type number should be found near your model number. Go to this site and on the left is the box you will input your model number, it will ask for the type number, and then it will take you to a parts list. Click on the tab for diagrams, and there you go. I hope this helps, let me know if you have any other questions.

Cylinder is held in place by the bulkhead (plastic ring with 4 upright tabs). See parts list at www.toolpartsdirect.com. To remove cylinder carefully pull /pry up bulkhead. Air leaking from nose is caused by debris/ worn orings in gun where bulkhead seals against body. Before you change any orings, remove bulkhead and examine condition of metal where orings contact body. Remove any scratches with 400 grit paper. Replace orings as needed. Dewalt used vinyl orings in your gun that fail due to oil breaking down the material. Your kit may contain vinyl orings, however black viton orings would be a great improvement (if available). Good luck.

Go to eReplacementParts.com : Power Tool Parts and Tool Repair and find a diagram and the parts you need.

We used nail guns for years. I still own 6 guns, but they aren't used much anymore.
You have a 'blown head gasket.'
Or there is debris from the air hose that got lodged into the gun.
There is a head gasket and a trigger gasket.
Both can blow out any time from use, lack of oil, or they can stick open from debris.
You can take apart the head and clean it up and add oil to see if that solves problem.
You can order a gun re-build kit for your model and put in the parts yourself.
You can have a nail gun repair shop do the job.

Nail guns require gun oil.
If you don't use gun for a while, oil should be put into air hose opening and then left to run down into gun. More oil is better.
If you use 3-in-1 oil or some oil besides gun oil, then it will corrode the gaskets.
When storing air hose and guns, put tape over openings so they stay clean.
Before hooking air hose to a gun, you can also put a blower on hose and blow out the line first

Sounds like the control valve mounted underneath the exhaust cap.First go to a parts store with tool info and get a rebuild kit.If you need more help or have question write back.