Crosman Town & Country 107

[jirushi]

So this morning I took the pump arms out of my 107 and 108.
The 108 arm was about half a cm shorter.
I adjusted the 107 arm to be exactly the same length.
But the 107 forearm still drops down when there's no air in the valve
And the forearm opens up again when I pump the cocked rifle and then open the arm up a little. So there's still a bubble of air in front of the pump cup, which should have gone into the valve.
Perhaps the 107 has a different position of the valve wall in de tube?
As in, further towards the rear of the rifle, so that I actually need to make the pump arm quite a bit longer than the 108 one?
From the outside the actions look identical.
Hmmm.
Will have to do more testing - hopefully tomorrow

[45flint]

So this morning I took the pump arms out of my 107 and 108.
The 108 arm was about half a cm shorter.
I adjusted the 107 arm to be exactly the same length.
But the 107 forearm still drops down when there's no air in the valve
And the forearm opens up again when I pump the cocked rifle and then open the arm up a little. So there's still a bubble of air in front of the pump cup, which should have gone into the valve.
Perhaps the 107 has a different position of the valve wall in de tube?
As in, further towards the rear of the rifle, so that I actually need to make the pump arm quite a bit longer than the 108 one?
From the outside the actions look identical.
Hmmm.
Will have to do more testing - hopefully tomorrow

Your 107 is a very early one and your 108 with the thin stock one of the last. Could be slightly different or built on a different station? Bottom line is your pump cup should be adjusted to the rifle. Lengthen it till it hits with about about 3/4 of a inch to go to full close. If your hitting at that point that last 3/4 inch will cam and keep the arm tight. If at that length your pump cup is not clearing the air hole it is strange? See my previous post.

[jirushi]

Your 107 is a very early one and your 108 with the thin stock one of the last. Could be slightly different or built on a different station? Bottom line is your pump cup should be adjusted to the rifle. Lengthen it till it hits with about about 3/4 of a inch to go to full close. If your hitting at that point that last 3/4 inch will cam and keep the arm tight. If at that length your pump cup is not clearing the air hole it is strange? See my previous post.

Yes this morning I went the "easy way" by using the 108 pump arm as an example.
As this didn't work, I will have to follow your, ped's and DTFletcher's info to find the correct length.
I'll get there in the end...

[DT Fletcher]

Yes this morning I went the "easy way" by using the 108 pump arm as an example.
As this didn't work, I will have to follow your, ped's and DTFletcher's info to find the correct length.
I'll get there in the end...

Setting the pump arm length is one of the simplest task to accomplish with these guns. Not sure why you're trying to make it complicated. There is only one way to set the pump length and that is the factory way, as has already been described; i.e. to the point where the pump arm over toggles (some incorrectly call this camming) and leave it there. There is simply no point in obsessing about the air hole. In my entire career of repairing these guns, I never once came across a problem with the air hole. I never even look at it since there's no reason. After all, what are you going to do about it? Drill another hole? You can't adjust the pump arm length to accommodate, since you end up with a gun that doesn't function properly.

As I've tried to explain, if that hole isn't doing it's job, the gun simply will not pump up. In short: stop worrying about the air hole!

As for the low power, the first thing to check is the pump head washer; if the pump head washer leaks at high pressure then the gun will not fully pump up and the power will be low. Very few other things can cause that. So, I suggest getting a replacement pump head of the original style with a new pump head washer.

[--ped--]

personally think the original seals are crap and would only use to keep it original and tbh I'd even then not fit it but have it so it could be returned to original
with modern materials and methods I'd fit an o ring conversion
as to the terminology of the action of the lever locking against tube i'll still call it camming over despite what anyone says as the action is more akin to that as a toggle goes through a loop to fasten two items together

[jirushi]

personally think the original seals are crap and would only use to keep it original and tbh I'd even then not fit it but have it so it could be returned to original
with modern materials and methods I'd fit an o ring conversion
as to the terminology of the action of the lever locking against tube i'll still call it camming over despite what anyone says as the action is more akin to that as a toggle goes through a loop to fasten two items together

Hi ped I bought 2 pump arms with leather seals from JH Airguns yesterday. I shall be sending one of them to you if that is ok
As a part exchange for one of your o-ring conversions.
Would be fantastic. If you want me to order other things from them for you, please let me know per pm.

Thank you DTFletcher for the advice. I will adjust the pump arm length later and stop focussing on the air hole

[45flint]

Toggle in the dictionary:
a device consisting of two bars jointed together end to end but not in line so that when a force is applied to the joint tending to straighten it pressure will be exerted on the parts adjacent or fixed to the outer ends of the bars.

I think DT got this one.

[DT Fletcher]

Hi ped I bought 2 pump arms with leather seals from JH Airguns yesterday. I shall be sending one of them to you if that is ok
As a part exchange for one of your o-ring conversions.
Would be fantastic. If you want me to order other things from them for you, please let me know per pm.

Thank you DTFletcher for the advice. I will adjust the pump arm length later and stop focussing on the air hole

Well, to adjust your pump arm without proper over toggling would result in a "droopy" forearm lever... which I cannot abide. ;-)

[DT Fletcher]

personally think the original seals are crap and would only use to keep it original and tbh I'd even then not fit it but have it so it could be returned to original
with modern materials and methods I'd fit an o ring conversion
as to the terminology of the action of the lever locking against tube i'll still call it camming over despite what anyone says as the action is more akin to that as a toggle goes through a loop to fasten two items together

Original seals crap? Completely agree. They do work but that's about it. I strongly support the fitting of a modern design valve with modern materials. Hell, I'd even go for modifying the exhaust body. There's nothing special about the T/C exhaust body; it's exactly the same as all the others in the class.