Crosman Town & Country 107

[--ped--]

all the piston heads I have are the same as yours Louis and as you've seen this type are rebuildable but usually they were rebuilt by the service centres(you can get them from JG on an exchange basis still)
is the rod adjusted correctly and these seals are designed to squeeze a bit on opening and expand when pumped so they sealed to the tube
how much more clearance do you need can you shave a bit off the piston pivot block so the lever opens a touch more
on one of my 140's and a Sheridan I found I had to slot the breeth hole a fraction when fitting upgraded pistons

[jirushi]

all the piston heads I have are the same as yours Louis and as you've seen this type are rebuildable but usually they were rebuilt by the service centres(you can get them from JG on an exchange basis still)
is the rod adjusted correctly and these seals are designed to squeeze a bit on opening and expand when pumped so they sealed to the tube
how much more clearance do you need can you shave a bit off the piston pivot block so the lever opens a touch more
on one of my 140's and a Sheridan I found I had to slot the breeth hole a fraction when fitting upgraded pistons

Good ideas. I will check later re the clearance.
Do you know if the rod can be turned into the piston pivot block?
This would be the logical way to adjust the length of the rod?
Well, the answer lies at home hehe.

[45flint]

I’m mixing threads from the other forum but you said your pump arm was welded to probably put on the new pump cup? If you are now finding that it was not adjusted correctly he may have given up? It may be why your rifle is in such good shape, it wasn’t used after that? I’ve seen that with other vintage rifles, sometimes the ones in excellent shape broke and they were never fixed? Good thing is this is a easy fix, I bought one from Rick for a Crosman 101 that had a leather pump seal. Worked great and was not much money. I like you wanted to keep the original but in the end I used the new one cause I would be the only one that would know anyway.

[jirushi]

I’m mixing threads from the other forum but you said your pump arm was welded to probably put on the new pump cup? If you are now finding that it was not adjusted correctly he may have given up? It may be why your rifle is in such good shape, it wasn’t used after that? I’ve seen that with other vintage rifles, sometimes the ones in excellent shape broke and they were never fixed? Good thing is this is a easy fix, I bought one from Rick for a Crosman 101 that had a leather pump seal. Worked great and was not much money. I like you wanted to keep the original but in the end I used the new one cause I would be the only one that would know anyway.

Yes I asked for Rick Willnecker's advice and he says part of my pump rod comes off a 1400.
I don't really mind tbh, as long as it works (as you point out).
Luckily, this rod is easy to adjust in length. Pfew.
It took a few attempts to get the length just right.
Now the cup clears the "breathing hole".
However, I'm not there yet...
The gun is very low on power (about 3.5 ft/lbs with 8 pumps. I've tried 15 pumps, the pumping is way too easy - 4 ft/lbs).
Hmmm.
It doesn't seem to be leaking. But I can't be sure. I am sure that the new seals are fitted correctly in the compression chamber. I've lubed them with a bit of silicon grease.
I didn't bang the brass nut all the way down onto the pump cup base; I left a bit of space to make it easier to replace the cup next time. I can't see how this would cause low power though.
One thing that struck me, is that the check valve spring in Rick's seal kit is about 1 cm longer than the one that was in the gun.
The gun now contains Rick's spring.
Perhaps the check valve cannot open properly with this stronger spring?
My 108 is perfect though, and Rick resealed that for me a few months ago; I'm sure he used this same spring.
And I don't think that the 108's internals are any different from the 107?
Hmmmmmmm

Any ideas?

[draitzer]

Louis, if you left the brass retainer piece sticking out proud of the pump cup, then you've got excess 'dead space' in front of the piston cup which means the full gulp of air for each pump is not going into the valve chamber. Either pressing it all the way on or cutting it flush with the front of the cup will remedy this (also explains why your cup didn't clear the breathing hole with lever opened all the way: your overall piston head assembly is longer than normal). Obviously you'll need to re-adjust the rod length to compensate, so as to have the piston bottom out against the valve again.

Don R.

[45flint]

Louis, if you left the brass retainer piece sticking out proud of the pump cup, then you've got excess 'dead space' in front of the piston cup which means the full gulp of air for each pump is not going into the valve chamber. Either pressing it all the way on or cutting it flush with the front of the cup will remedy this (also explains why your cup didn't clear the breathing hole with lever opened all the way: your overall piston head assembly is longer than normal). Obviously you'll need to re-adjust the rod length to compensate, so as to have the piston bottom out against the valve again.

Don R.

I think Don’s got it. I bet it’s your pump cup? Also in not tapping down the brass collar firmly, air may be escaping through the cup? One way to see if it’s the cup let the charge you are getting stand overnight if it holds then you are not getting the air in? Pump cup and adjustment? But I’m a rookie, so what do I know?

[--ped--]

I would agree that it is the piston head leaking air past on the compression stroke and would press the brass collar on further
as it's not a genuine piston but a later one I'd if all else fails put an o ring piston in it

[jirushi]

Louis, if you left the brass retainer piece sticking out proud of the pump cup, then you've got excess 'dead space' in front of the piston cup which means the full gulp of air for each pump is not going into the valve chamber. Either pressing it all the way on or cutting it flush with the front of the cup will remedy this (also explains why your cup didn't clear the breathing hole with lever opened all the way: your overall piston head assembly is longer than normal). Obviously you'll need to re-adjust the rod length to compensate, so as to have the piston bottom out against the valve again.

Don R.

Hi Don R., thank you for your advice. Cutting the alu base and brass retainer piece flush might be a good idea! After pressing it all the way on, the pump cup still isn't protruding. The breahting hole is clear now though.

[45flint]

“An o-ring pump head would be a great idea, to test the difference. The problem might still be the cup not sealing well enough. A hint towards this theory is that pumping becomes harder up to 8 or 9 pumps, but then it's not that much more difficult to go 12 pumps, and the velocity increase is marginal. Maybe the pump is then simply not coping with the pressure, and leaking air - without me hearing it. “

That doesn’t sound right, should be harder to pump with each stroke?