Tuning Benjamin Bulldog Not Taking Air

[capnbo]

Need help trouble shooting the cause my Benjamin Bulldog will not take air. it had not been used for 4-5 months and was a little low on air. Connected to my bottle and brought it back up to maximum pressure. When I bled the fill line from the tank and disconnected the Foster fitting, air was slowly leaking back out. I emptied the air reservoir and filled again, same slow leak. I then took the male Foster fitting off the bulldog hoping to find signs of trash or water but it looked normal. I put the fitting back on and tried to fill and now no air can be sent to the air reservoir. Any ideas what could be wrong ? Thanks.

 

[Odoyle]

You fitting is probably plugged. Simple disassembly and clean then reinstall.

 

[cmatera]

I’m no expert, but when mine had air leaking out of he male foster, my gunsmith had me degas the gun by slowly draining the gun of air using the drain screw in front of the male foster, then take a small hex key put it in the hole of the male foster fitting and push up a little. There is a spring loaded valve in there, and it reseated it. He also said when bleeding the air from the hose, do it fast. If there is little to no air in the gun make sure to cock and leave the cocking lever open until the gun starts to take air AFTER making sure the gun is unloaded and the safety is on. When done, immediately decock the gun.

 

[Odoyle]

His Bulldog may have a mesh screen just inside the end off the male foster nipple so I am not sure if that would work.

 

[cmatera]

Might not, it did for me (on a brand new gun). If it happens again, I was told to just wrench it out and replace it, it’s cheap enough. If I do I’ll keep the old one and clean and reassemble it as a spare.

 

[Raden1942]

My Crosman foster fittings have done this before. Take it out after degassing clean and reseat the check valve. If there is a mesh in there I would try blasting some air in it with a shop compressor with a filter on it or something. Mine just had a piece of debris blocking the check valve. If none of these solutions work Crosman will send you another one if it's within warranty. If not it's probably less than 20 bucks for a new fitting. 

 

[capnbo]

Thanks everyone for your responses and suggestions. I will order a new Foster fitting today and try the other steps to get the gun charged. I will let you know if I am successful.

 

[FuzzyGrub]

FWIW: The filter is in the tip of the male foster on the BD. It does not have a filter between it and the adapter that screws into the breech. You want to order the replacement from crosman for that, and to make sure the check-valve works with the pocket in the adapter. Some aftermarket ones may drop down too far. Taking it apart, cleaning, and a little silicone oil would probably fix the existing one.

 

[capnbo]

Update: Ordered new Foster inlet/check valve from Pyramyd Air and installed on the BD this morning. Left the cocking handle open and the BD took air and is holding without leaking down. Will check the pressure tomorrow to make sure there is not a slow leak. I appreciate everyone's help you gave me to resolve this issue. The nocturnal hogs visiting our corn feeders are once again in harms way! Thanks!!