FWB 65 problem

PaulB · Post by **PaulB** » Wed May 11, 2011 8:50 pm

A thirty year plus old FWB 65 has a significant amount of what appears to be small pieces of a very light brown waxey substance inside the piston. You can see it through the hole in the conical breach seal. An amount of it blows out every time you shoot. It does not seem to effect velocity or accuracy. I am sure that it is not supposed to be there. What is it? How can I clean it out?

Greg Derr · Post by **Greg Derr** » Wed May 11, 2011 9:44 pm

Sounds like a seal is breaking up, they tend to turn reddish brown and fall apart with age.

Gerard · Post by **Gerard** » Thu May 12, 2011 3:59 am

From what I understand of the 65 (and I am not a gunsmith, so take it with a grain of salt) this is not a seal exactly, but a piston head bumper. Not sure of the name really. But the 65 uses a steel ring on the piston to do the job of sealing. The plastic (delrin?) head bumper is just there to prevent the piston slamming against the cylinder end and transfer port. A tear-down is in order and a new plastic part should be installed once everything has been well cleaned and lightly lubricated with an appropriate oil.

Cones · Post by **Cones** » Thu May 12, 2011 7:01 am

It is as has been already stated the piston buffer, it needs replacing. I would also replace the seal and the small plastic button below it as well.

I have written a complete guide on the thread below.

http://www.airgunbbs.com/showthread.php ... u-Model-65

Strip guide here

http://www.airgunbbs.com/showthread.php ... ost4545004

If you are in doubt about servicing it yourself then I am sure someone else like the forum sponsor should be able to help.

HTH

Mark

PFribley · Post by **PFribley** » Thu May 12, 2011 8:33 am

I recently had my FWB C55 gone over by the moderator(Pilkguns). I highly recomend them if you don't want to tackle the job yourself. The service was handled in a professional,timley manner. In my opinion they did not overcharge. They repaired all of the issues with the pistol. It worked as good as new when returned to me. I will not hesitate to use there services. I have a FWB65 that has a trigger that I am not happy with. Am considering sending it to them for a going over. This is based on my previous experience with them.

kevinweiho · Post by **kevinweiho** » Thu May 12, 2011 4:08 pm

Both the piston washer and buffer should be replaced.

I think FWB updated the material of their seals and they are green in color.