Today reader RidgeRunner continues his a blog series on his experiences with the Crosman 150 air pistol. Today he starts to repair the 150 pistol I sent him. If you’d like to write a guest post for this blog, please email me at firstname.lastname@example.org.
Take it away, RidgeRunner
RidgeRunner’s Crosman 150 – Part One
The Crosman 150 I will be sealing.
This report covers:
- On with the show
- Removing the valve assembly
- The reseal
First thing I would like to do is thank BB for not only sending me this 150, but for being such a wonderful inspiration for so many of us and for his personal support for RRHFWA, which would not even exist if it were not for him.
Next, I would like to thank Derrick of Another Airgun Blog for writing and photographing his experience with resealing his 150. It was most certainly a big help to me.
I would also like to thank Dennis Baker and his gang for putting together so many seal kits, one of which I used on this air pistol.
I’m about to start.
On with the show
The very first thing I did was unscrew the front gas tube plug and remove the wonderful one-piece laminated wood grips by removing the two screws holding them to the frame and sliding them backwards. Many of the Crosman 150s that I have seen have two plastic slab grips — one on each side, but this one has some real nice grips. I may do something with them at a later date, but not right now.
The next thing I did was remove the screw holding on the rear sight. It also held the rear of the barrel to the gas tube, retained the rear barrel plug and also held the hammer/striker in.
This 150 has a breech cover that slides back to pull the bolt back for loading a pellet.
Next I removed the small screw from the breech cover. This allowed the cover to slide off of the rear of the barrel and also allowed the bolt to slide out of the back of the barrel.
For my next trick, I removed the screw holding the front sight to the barrel. The front sight on this 150 is plastic, but the one on Quinn’s is metal. I may have to look for one of those. [Editor’s note: The metal sight is original to the gun. The plastic sight is a replacement Crosman made in latter years.]
After starting this is what I had.
Now that the bolt is out of the way, I can access the screw that is still holding the barrel onto the gas tube. With this screw removed, the barrel just falls off of the gas tube, revealing the transfer port and its gasket.
The next thing I do is remove the two screws holding the grip frame and trigger assembly to the gas tube. They also just drop away now. All this leaves is the valve assembly and the stop block still in the gas tube. This is also where it got a little tricky.
Everything except the valve assembly and stop block are now out.
Removing the valve assembly
I took a long, hard look at Derrick’s blog to determine just how he removed the valve assembly from this tube. How did he get the valve stem out of the way to remove the stop block pin? In his blog he took a long, thin pin and pushed on the valve stem with it and then knocked the stop block pin out. Well, I took my small pin punch, but no matter how hard I pushed, the valve stem would not get out of my way.
What I did not realize is when Derrick pushed on the valve stem, his valve assembly slid forward. This one did not. I then took my rubber mallet and hammered on the punch until the valve assembly did slide forward enough to allow me to remove the stop block pin. After that the stop block just slid right out of the back of the gas tube and allowing me to use a larger punch to push the valve assembly out of the front of the gas tube.
Once this was accomplished, it was a simple matter of unscrewing the back of the valve assembly to get it apart and start resealing.
The valve disassembled.
In the kit I purchased from Dennis and the gang were two white o-rings, a small black o-ring, a large black o-ring, a soft black transfer port gasket, a new spring and a new valve stem.
The white o-rings go — one on the screw-on cap and the other on the front of the valve assembly. The large black o-ring goes on the inside of the back of the valve assembly. You can probably figure out where the valve stem and the spring go. If these give you any trouble, you had better not be doing this.
The small black o-ring goes on the bolt and you can probably figure out where the transfer port gasket goes.
Now it’s time to put it all back together. Really, it is not that bad. The first thing you should do is clean the gas tube. Mine was pretty cruddy. That may be why the valve assembly did not just slide out.
After cleaning, I inserted the stop block and pin. Next thing I did was push the valve assembly in place, making sure the threaded hole in it lined up with the screw hole for the grip assembly screw. From here on out reassembly is just the reverse of taking this apart. Even I could do it.
This took a lot longer for you to read about than for me to do it. Next time around I will shoot this thing across my chronograph and see how fast it is.