I did find one shredded o-ring when I took the gun apart. With the kit I got it doesnt seem the the gun is getting a good seal around the bulkhead /cylinder spacer. I have a type 1 dewalt D51844. The plastic bag the kit came in does have my model number on it. Only one of the only rings that go under (inside) the bulkhead is the clearer color. Both of the ones I removed were clearer. Also I seem to have one o ring left over. Maybe that is because one of the other models or types takes an extra one ring. Please advise. The only other option I can think of is to pull the trigger out and check those o rings. Im just not finding info online that would indicate those o rings as the problem I am having. The gun does shoot nails but they only drive in half way 5do to the loss of air out of the nose of the gun.
The seal # 390140-00 installed on the upper part of the cylinder will allow air to come out the nose of the gun as well as the bulkhead orings as you suspect. Here is what I do the check the fit of the clear or vinyl orings on the inner side of the bulkhead. Remove both of the orings from the cylinder that come into contact with the inner side of the bulkhead. INstall one oring on the cylinder first then slip bulkhead on to check for snug /firm fit. If the one oring feels loose add a couple turns of Teflon tape under the oring and repeat test until contact feels firm but not too tight. Then remove this oring and try the other oring for fit and do the same if it feels too loose. When the second oring feels good go ahead and install both orings and re-assemble. It should work. I do not like the vinyl orings that come in the kit, I usually order buna orings to fit from "orings and more" on the internet, they sell orings by size so you must order the size needed. If you do not know how to measure the orings for size, take the orings to a hydraulic store or a bearing shop and they will tell you what size they are. vinyl orings do not last like the buna . Good luck
SOURCE: Dewalt Nail Gun D51844. Same problem as other guy
Dewalt uses about 4 or 5 orings within the gun made of semi clear urethane that fail (turn gummy and breake apart). Two are under the bulkhead and at least two in the trigger valve. To remove the bulkhead pull up on the white housing. With housing and cylinder assembly out, push down on the black retainer at the very bottom and remove the oring(take a picture of the assembly after each stage so that you can re-assemble the spring and checkvalve correctly). You will find two large orings under the bulkhead against the cylinder that need to be replaced (also the orings in the trigger, or replace the trigger valve ).
483 views
Usually answered in minutes!
×