More woes with my sumatra carbine :-(

[rovercoupe]

Could it have had the valve messed with in the past and now it takes a real heavy spring to open it and the transfer port is doing it’s job of restricting the power back down to sub 12 levels?

[Shed tuner]

the valve is steel. the hammer is steel. the mushroom head on the valve stem is synthetic (delrin ?), encased in brass. the (inner) valve face is steel.

so the only way it cannot fire is if the valve stem delrin mushroom is not being knocked away from the sealing face of the valve. generally, the only things that hold it in place are air pressure (hence you pressure lock situation) and the valve return spring.

this is why I suggested the power adjuster (which limits and can block) valve stem travel be checked first.

[WILBA]

Could it have had the valve messed with in the past and now it takes a real heavy spring to open it and the transfer port is doing it’s job of restricting the power back down to sub 12 levels?

Gun has not been messed with i know that.

[rovercoupe]

Hmm,just a thought but does it have a plastic restrictor on the valve stem? Could this have swollen and it’s stopping the hammer from getting to the stem?

[Shed tuner]

Hmm,just a thought but does it have a plastic restrictor on the valve stem? Could this have swollen and it’s stopping the hammer from getting to the stem?

or somehow jammed.. yeah, good point.

[WILBA]

or somehow jammed.. yeah, good point.

I have removed the hammer before. How do i get to the valve stem jon? Is that restrictor on the valve stem or the valve?

[WILBA]

Is the valve stem also known as the exaust valve? as thats what shows up when i look for a new one online.

[rovercoupe]

Yes the exhaust valve is the valve stem, from what I remember it’s a plastic disc that sits around the stem to stop the hammer from hitting it too hard and causing excess power. It’s been a while since mine was apart so cannot be sure what it looks like.

[WILBA]

Ordered an uprated valve stem. Will fit it and see if this fixes the problem. If not will send it away for inspection and repair.

[WILBA]

Hmm,just a thought but does it have a plastic restrictor on the valve stem? Could this have swollen and it’s stopping the hammer from getting to the stem?

What does the restrictor look like as i hsve no idea what i am looking for.