TargetTalk

I have a Morini cylinder that is rated for 20 years, and still has 7 years of life. I know I can't use it in competition, but it should be fine for practice, except it has developed a slow leak. It will drop from 200 bar down to ~ 130 bar over the course of a week. I'm not sure if it's the gauge end or the valve/fill end.

In a rational world, I could send it to Pilkguns for repair. However, they apparently no longer work on cylinders more than 10 years old, independent of what the manufacturer says about their safe working life.

If it's the valve end, I'm perfectly capable of fixing it myself, IF I can get parts. Does anyone know if there are vendors (probably in Europe) that sell rebuild kits, or do they use standard O-rings?

My one concern is that I've heard that the gauges can be an issue. I don't know if the gauges tend to leak internally, stop gauging properly, or if it's just the seal to the tank that tends to leak.

Any thoughts or ideas? Yes, I know I can buy a new cylinder. It just irks me to spend $200 for a 20 year cylinder, only to have some European bureaucrat wave a pen and turn it into scrap.

Thanks!

Gwhite wrote:... I'm not sure if it's the gauge end or the valve/fill end.
...do they use standard O-rings?

Put it in a bucket of water, that will tell you which end is leaking.

As for O rings, I'm not sure, but I would be surprised if they were not standard metric sizes (but usually a harder grade, rated for high pressure). I can't speak for Morini cylinders but Steyr are standard sizes and are easy to put new seals in, once the valve end is out you use a long hex key to get the gauge out from the inside.

And, I agree, why should you buy a new one when yours is still useable (once you fix the leak).

j-team wrote:

Gwhite wrote:... I'm not sure if it's the gauge end or the valve/fill end.
...do they use standard O-rings?

Put it in a bucket of water, that will tell you which end is leaking.

As for O rings, I'm not sure, but I would be surprised if they were not standard metric sizes (but usually a harder grade, rated for high pressure). I can't speak for Morini cylinders but Steyr are standard sizes and are easy to put new seals in, once the valve end is out you use a long hex key to get the gauge out from the inside.

And, I agree, why should you buy a new one when yours is still useable (once you fix the leak).

I was thinking about putting the valve end in a bucket of water. That will be easy to dry out. I don't think I want to try that with the gauge end... If it doesn't blow bubbles from the valve end, I'll assume it's the gauge end.

I did find some info on-line with a list of the sizes of the O-rings. They all appear to be standard sizes, but I may have trouble sourcing them in a harder material. Unfortunately, the valve seal (which has been the culprit in the past for others) is just listed as a green Viton O-ting with no size info. It is part No. 162010A.

I wouldn't assume that it's one end or the other. If there's a slow leak, it could be the cylinder wall as well, especially since it's that old. Test everything and proceed carefully. That hole could rupture and send the whole thing flying off...somewhere. Pray it's not in your direction or that of someone you care for.

Seriously, don't screw around with something you're keeping under around 3000 PSI. If I were you I would drain the cylinder completely and slowly add a bit of air, then do the complete test. Don't use it for anything else until you've figured out what is going on. I know that APs are not as dangerous as firearms, but they deserve our respect in the appropriate places. This is one of them.

Chia wrote:I wouldn't assume that it's one end or the other. If there's a slow leak, it could be the cylinder wall as well, especially since it's that old. Test everything and proceed carefully. That hole could rupture and send the whole thing flying off...somewhere. Pray it's not in your direction or that of someone you care for.

Seriously, don't screw around with something you're keeping under around 3000 PSI. If I were you I would drain the cylinder completely and slowly add a bit of air, then do the complete test. Don't use it for anything else until you've figured out what is going on. I know that APs are not as dangerous as firearms, but they deserve our respect in the appropriate places. This is one of them.

Sheesh! I suppose that's to be expected from a lawyer!

Gwhite, go ahead an reseal your cylinder and keep using it!

The cylinder in question has seen VERY light use, and has lived in a temperature controlled environment. If a cylinder is going to fail from age, it is most likely due to the number of times it's been filled, and how much of a pressure swing it's been exposed to each time it's filled. I top mine off with a handpump, so they also haven't seen wild pressure swings from filling from empty.

Morini had no problem putting a 20 year service life on these cylinders for many years. The current 10 year limit is ENTIRELY due to politics & money, and has nothing to do with the inability of the manufacturers to make cylinders that are safe for that long. Plenty of people have experienced leaky Morini cylinders for seal issues. I have yet to hear of ONE that was a flaw in the cylinder itself.

does it leak if you leave it in the pistol? If not then its the filler valve. I had a P34 that only ran down out of the gun. It did not show any leak with soapy water from a brush yet over 2 weeks it would lose 100 bar. Had it serviced for the equivalent of $50 even though FWB couldn't detect a leak at first.
Re leaking through the side wall, unlikely without total catastrophic failure!

Gwhite wrote:The cylinder in question has seen VERY light use, and has lived in a temperature controlled environment. If a cylinder is going to fail from age, it is most likely due to the number of times it's been filled, and how much of a pressure swing it's been exposed to each time it's filled. I top mine off with a handpump, so they also haven't seen wild pressure swings from filling from empty.

Morini had no problem putting a 20 year service life on these cylinders for many years. The current 10 year limit is ENTIRELY due to politics & money, and has nothing to do with the inability of the manufacturers to make cylinders that are safe for that long. Plenty of people have experienced leaky Morini cylinders for seal issues. I have yet to hear of ONE that was a flaw in the cylinder itself.

Hey, if it's what you want to do, I won't stop you. It's your cylinder and you know it better than me. I was relying on a set of information that seemed to indicate that a rupture could be a possibility. If you don't think it is, than do what you need to do, and I apologize if I caused offense. It was not done out of malice.

And yes I know that "sounds like something a lawyer would say." That's because we all get a lovely set of classes on something called negligence and products liability. We spend an entire semester listening to lovely things like why wood shredders are now equipped with an emergency switch and about who is liable if a person is ordered to use a blowtorch near unlabelled oxygen tanks (everyone, probably including the manufacturer of the oxygen tanks). Personally, I can't go ride on state fairground rides anymore.

Anyways, sorry for the interruption.

TenMetrePeter wrote:does it leak if you leave it in the pistol? If not then its the filler valve. I had a P34 that only ran down out of the gun. It did not show any leak with soapy water from a brush yet over 2 weeks it would lose 100 bar. Had it serviced for the equivalent of $50 even though FWB couldn't detect a leak at first.
Re leaking through the side wall, unlikely without total catastrophic failure!

Mine leaks off the pistol, at a rate of about 100 bar a week. I've found that Cibles in Canada has seals. There is apparently quite a variation in the cost of a set of seals, due to multiple design changes over the years. We are going back & forth to see what version of seals mine might require. I may have to open it up to find out.

In the meantime, I'm thinking about how best to make a pair of close fitting wooden blocks to clamp the cylinder in a vise.

My question was does it leak in the gun?
If not its definitely the non return fill valve in the cylinder. Just trying to diagnose for you. I would strongly favour professional servicing. Clamping in a vice even with blocks is maybe scary with a pressure vessel that delicate.
Also I replaced a perfect cylinder at 10 years because I value my face.

I agree that it is most likely the fill valve. As for getting it serviced "professionally", nobody will touch it because it's more than 10 years old.

I have a full machine shop in my basement, and have worked with pressure vessels in the past. I'm not going to do anything to compromise the integrity of the cylinder.

I've had 3 Morini gauges replaced because they were leaking, it's far from unusual.

Don't be afraid of putting that end in water. The part where the needle sits is low pressure. The (plastic) glass just levers off.

David Levene wrote:I've had 3 Morini gauges replaced because they were leaking, it's far from unusual.

Don't be afraid of putting that end in water. The part where the needle sits is low pressure. The (plastic) glass just levers off.

Good to know. I suppose I can flush it with alcohol and/or pack it in desicant afterward. I'm hoping it will blow bubbles from the valve end & I will know for sure. I'm hoping to have time to do the dunk test this weekend.

There are a couple of models of tank pressure indicators, the early one (diamond needle shape) is the common
one to leak.
I have found that the tank seals dry out and crack between 7-10 years and leak, these are easy to replace.
If it is the valve then you need to strip the tank so replace all seals.
if it is the indicator then it requires replacement.
Some years ago we increased the hardness of the seals from Nitrol 70 to Nitrol 90 and the life increased.
Don't worry about wooden blocks for the tank clamp, heavy leather and a good machine vice with nylon soft
jaws works well. I have also used 10mm rope (multilpe turns to make a Spanish Windlass on a range with no workshop).

Cyl. Tank ends 162007A 23mm x 1.5mm
Fill Valve 162020B 3.8mm x 1.2mm

I would prefer to dunk or dribble the gauge end in thin sewing machine oil or pelgun type oil than water. Its a method promoted by Air Arms for testing their PCP components and they released a number of youtube videos on the subject. When I replaced my Air arms cylinder gauge I used that method. Water and small brass gear wheels have a poor prognosis.

David M wrote:There are a couple of models of tank pressure indicators, the early one (diamond needle shape) is the common
one to leak.
I have found that the tank seals dry out and crack between 7-10 years and leak, these are easy to replace.
If it is the valve then you need to strip the tank so replace all seals.
if it is the indicator then it requires replacement.
Some years ago we increased the hardness of the seals from Nitrol 70 to Nitrol 90 and the life increased.
Don't worry about wooden blocks for the tank clamp, heavy leather and a good machine vice with nylon soft
jaws works well. I have also used 10mm rope (multilpe turns to make a Spanish Windlass on a range with no workshop).

Cyl. Tank ends 162007A 23mm x 1.5mm
Fill Valve 162020B 3.8mm x 1.2mm

Thanks for all the info. The data I have found earlier lists:

162008A MORINI O-RING 23 x 1.5mm (Air Cylinder Seals)
162010A MORINI O-RING (Air Cylinder Air Release Unit Green Viton) <- Fill Valve seal

This is probably for earlier cylinders. Mine looks like:



My usual source for O-rings is McMaster Carr, and they have most of the various sizes, but many of them aren't available in Durometer 90. I can get some in Viton with Durometer 75, but that's not much difference. They also don't carry anything as small as the valve seal. For now, I'll probably get a seal kit from Cibles, but I may do some more digging to find a US source for the right O-rings. The team I help coach has a number of Morinis as well, and I suspect this won't be the only leak I have to deal with.

TenMetrePeter wrote:I would prefer to dunk or dribble the gauge end in thin sewing machine oil or pelgun type oil than water. Its a method promoted by Air Arms for testing their PCP components and they released a number of youtube videos on the subject. When I replaced my Air arms cylinder gauge I used that method. Water and small brass gear wheels have a poor prognosis.

Thanks for the tip. I was planning on checking out YouTube for testing ideas. The valve end is easy, because all I need is a very thin layer I can stand the cylinder up in. The gauge end requires a lot more oil & clean-up, so I'm hoping it blows bubbles from the fill end & I'm done. I have lots of RemOil, which is quite thin.

You may want to remember, that if air is going out NOTHING is going in. I use water.

Rover wrote:You may want to remember, that if air is going out NOTHING is going in. I use water.

On the valve end, it isn't an issue. On the gauge end, there is a vent hole in the side of the gauge that would be above the level of the gauge face. That means it's quite likely that the gauge will get water in it to some extent.

I've been told that getting water in the gauge doesn't do any damage, at least for brief exposures. It still makes me nervous.

It really is not rocket science...
Put a little bit of sticky tape over the hole, if the gauge is leaking it will force a bubble and lift the tape.
Or mix some detergent and water 50/50 and wipe over the joints it will bubble if leaking.