Found something odd on a OLD Dan?

[Nvreloader]

Guys

I just stripped down my oldest Dan, 50 yr model, when I got the valve out, (leaking and not holding air),
while cleaning up every thing from all the years of use and sitting around etc,
I found something I have never seen, in a Dan. (in my limited experiences with Dan's)

The poppet head and the inlet valve had 4 very tiny holes spaced equal distance around them,
and the retainer nut was brass, (instead of steel), it had 2 lead seals.

Any guess why, the holes?

Thanks,
Don

[pgritty]

Picture maybe.
Pat

[eeler1]

What’s odd?  4 ports is pretty common.

[Nvreloader]

Jon

I am talking about the poppet (exhaust) head and inlet valve had these tiny holes around the radius,
see info here, bottom of pg #9, for names and locations etc.
http://ujays.net/sheridan-manual.pdf

The main valve did also have the standard 4 holes..........

Thanks Guys,
Don

[RodJ]

Don,
I’m new to some of the terminology, but I think you’re saying that the poppet on the outlet has 4 holes, and the check body in the inlet valve has four holes.  Do the holes go all the way through, and to where? The center, other side, or ...? When the poppet and check body are seated in their respective seats, are the holes then blocked?

Never having been inside, I wouldn’t know whether the holes are supposed to be there, but I’m trying to understand how the valves hold air with holes in them, unless they are blocked off when seated.

Rod

[Nvreloader]

Rod

There is brass material, cup like holder formed around the end of the poppet stem and check disc,
that contains the sealing material rings for each part.

These very tiny holes (-.040" in size) are drilled thru the brass cup material only, that holds the sealing rings, on both pieces.

All the holes are NOT sealed in any way, except what is being sealed by the sealing ring material only,
when formed around the cups.

Just kinda weird that both parts are the same for the hole size and spacing etc.
 
IMHO, they are OEM from when this early 50's Dan was made, I was hoping some of the older Dan collectors might know why etc.

Thanks,
Don

[oldair]

Don, I've taken apart quite a few old Streaks and never seen holes as you describe.  The only reason I can think of for them would be for a tiny prybar to remove the seal if replacing the elastomer (usually folks just replace the whole thing with new ones).  It would be good to see pic's of what you have.

Don R.

[Nvreloader]

Thanks Don R

I'll try, the last time I tried posting the photo's came out TOO big and I could not get them posted etc.

Don

[RodJ]

Don, Thanks for the further description.  My knowledge is near zero on these rifles, but I was wondering what function the holes might play. Am stumped.

On the bright side, I figured out how to reduce the file size on photos.  If you send them by email to me, I can reduce and send back to you. Let me know if I can help with that.

Thanks for your helpful responses on my Sheridan post.

Rod 

[Nvreloader]

Rod here are a couple photo's, Looks like only 1 photo came thru, but you can see the tiny holes etc.

href="https://ibb.co/QfFbSkp">[/url]

Hth's

Don

[RodJ]

Interesting. They remind me of gas flow holes inside oxy-acetylene torch handles right in front of the mixing chamber where oxygen flow is controlled.  Makes no sense in the context of check and poppet valves.

Remind me, old is your rifle?  If I were forced to consider EVERY POSSIBLE possibility, one would be that Sheridan adapted extra / overstock OA valves to create the rifle.  And when those ran out, they just got more but didn’t need the holes (assuming the later guns didn’t have these holes).  But that’s just a nonrealistic guess for the sake of speculation (and maybe spurs some real ideas).

Thanks for the photo. Fun to speculate. 

[oldair]

Thanks for the photo.  It inspired me to rummage through my drawer of old dead Sheridan/Benji valves and sure enough, I have two exhaust valves with holes! They look to be ~ .030" dia, easy to overlook when dirty - my original statement was Wrong.  Now it makes me wonder if the holes were to assure no air got trapped beneath the seal when these were assembled?
Also found a couple intake valves with the same outer 'bell shape' but no holes.  Looking at my 'collection' it's apparent that valve details varied somewhat - straight-sided cups with differing heights, flat brass base with no cup, and the 'bell' shape with/without holes.

One question: It looks like the stem of your exhaust valve has an enlarged brass portion (barely visible) where it runs into the rubber material vs normal straight steel stem of 5/32 diameter...am I seeing it right?

Don R.

[Nvreloader]

Don R

I have two old valves, the one with the holes has a poppet shaft diameter of .153-4" and is straight shafted,
the other valves shaft is .153-4" then steps up in size to .195" just before the rubber seal.

The hole poppet has a thickness of .285" for the cup part and is one solid piece and the other is .210" and is 2 piece,

Both valves have an inside throat diameter of .228",
there is a difference in length from 1.395" (hole poppet shaft) to 1.305" for the other old one, all other measurements are the same for both valves.

I am also finding up to 1/4" length differences of the poppet springs, and I got these 2 valve poppet spring mixed up........ , so I'll have to figure the average for length between the 2 valves, before installing them.

Thanks Guys,
Don

[eeler1]

No idea on th holes, Don.  But interesting, maybe Rod has it right.

[RodJ]

Big question just popped into my mind: does the presence or absence of holes make a difference in velocity??? 

And, does this create a “hole” new vintage subgroup of streaks to collect?    (pun intended)

[RodJ]

No idea on th holes, Don.  But interesting, maybe Rod has it right.

Not saying I’m definitely on to anything but didn’t the Sheridan streaks start right after WWII?  There would have be a lot of small aircraft torches (and parts) lying around.

[Nvreloader]

Thanks Guys

I don't have any Idea about the the fps readings yet,
I am attempting to figure out how to get the OLD sealing ring out of the cup base, and make a new sealing ring,
without messing up the cup or poppet head, so I can keep the OEM parts together, and reuse them etc,
then I can answer the fps question.............LOL   

So far both my sealing attempts have averaged right at 600 fps w/14.3 gr Crosman (Old) pellets at 8 pumps.

Don

[Brian W Cook]

I’m pretty sure the holes are to keep any high pressure air caught behind seal from blowing it out of the valve body .   My Crosman 101 valve has 1 hole in the side .

[oldair]

The Crosman 101 valve was intended for seal replacement (stem screws off, service centers had the 'valve washer' aka seal) and I'm pretty sure the side hole was intended for prying out the old seal.  It's large enough for a jeweler's screwdriver or ice pick to be used.  The seal is well captured by the step in the stem which also prevents air from getting underneath the seal.

Sheridan exhaust & intake valves were not set up for replacing the seal.  No separate seal part was available, rather you just buy an exhaust valve stem/seal/cup assembly.   The style of brass cup in itself won't affect the velocity - it'll depend on variables of return spring strength, seal hardness, and stem length protruding thru the valve.  Definitely the tiny holes are not involved.

Don R.

[Brian W Cook]

Sounds plausible.   Digging those hardened up old seals had to be tiring .