Sheridan Sheridan Pre-C Series Repair Advice Requested

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pwcosol, a couple notes to your recent posts:
- The new 'button' style check valve is a direct replacement for the older 'flat washer' style.
- The smaller nose on your new exhaust valve won't be a problem; when everything is assembled the spring and valve will line up fine.
- I agree with others that the grey surface you think is plastic, is actually the old lead valve-body seal.
- Before I acquired a valve remover similar to the one mentioned in post #16, I just placed a pin punch though the hole of the simple tool and tapped it rearward with my trusty plastic hammer to coax out sticky valves. The threaded tool makes the job immensely easier, pulling them out trauma-free.

Don R.
 
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one thing you might want to do is clean the step inside the tube where that seal sat. IF theres any old seal left sticking on that step could lead to leakage. I kind of forgot the size but 3/8" wooden dowel diameter sounds right with a little 200 grit sandpaper attached to the end of the dowel makes a good cleaning tool. Should fit over the step and then you just twist back and forth a little bit. It will sand down to a clean ledge where the lead or delrin seal goes.l. When done swab and rinse out with acetone and alcohol all the insides of that tube. string all those parts as you saw in the image from the above post onto your tool.angled alittle up so they stay in place and guide it all back in . When it comes to a stop you will need to push down or into the tube to compress the spring and start grabbing a thread for the nut to grab. Go slow and feel carefully that the nut is in fact starting right on a thread. after you get so many turns in you can snug it down firmly.I just use a metal dowel thru the T hole of the tool for leverage. When setting the pump if you have those adjustable piston rods again memory thinking it may be 7 3/8" long piston rod fro cup edge to bottom . I use a metal rod 1/8 or 3/16th od thru the front hle that the pump linkage attaches to to temorarily allow the pump to go open and closed. Yu want that length to make the pump close with the wood handle still about an inch from fully closed position. So that slight pressure will snap the grip handle closed. Hope this makes some sense. I did mention to you that there are many generic like parts out there fittig the sheridan but really only the ones that follow the original size of the model C work the best. YEs the exhaust spring is tapered. The intake seal is brass with a rubber seal in it ,dont worry if theres no middle nub. Ive seen all white delrin checkvalves too. Ive also seen several washers in between but should only be one if all lengths are to spec. Many variations on the exhaust valve. Try to pick the longest one . I personally like the teflon (or is it delrin white seal over the lead seal . With a chrony 2 pumps and a JSB 13.7gr 20 caliber pellet (best one to use) should clock 350-380fps. AND 8 pumps shot out should leave no residual air as checked by recocking and shooting again without pumping .
 
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You guys are the best! When I got the check valve out found some slightly sticky, tar-like residue in the area. Also found what seemed like a granular black crud between that small brass washer and underside of the crown on the release valve. My thought it was some long deteriorated rubber "O" ring. Yet, that tar-like substance seems to only be in a few places, with the rest nice and clean. The pump tube was close to spotless so makes me wonder how it got into the air chamber. Will definitely give it the acetone/alcohol bath. I did note on the right side of the rear end cap with safety, where it meets the pump tube, a spot where someone did a bit of prying to ease it out. Perhaps I am not the first to get into the rifle since it left the factory (which might explain a lot). Lastly, attached pics of the completed valve remover/puller. Found one SAE eye bolt just large enough to re-thread to the metric size I needed and then cut a access into the loop. Got about 1/16 inch clearance between valve tool nut end and eyebolt, which swings up or down with no interference. Next time I pull a valve, it should come away with relative ease...

WOYO DP Modified 1.JPG


WOYO DP Modified 2.JPG
 
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Continuing the Sheridan Saga, mixed up a few ounces of the acetone/alcohol (70%) brew and initially dumped it into the forward end of pump tube. Wanted to get any oil, etc. out of there first. Next poured it in from the breech end. Cleaned that end out with aluminum .30 cleaning rod and two kinds of patches (which leave no lint). Lastly, cleaned out the forward end of pump tube with a 12 Ga. CR set. The mixture worked great! It dissolved the crud and was picked up by the cleaning patches. Looking from the rear end of the pump tube, I could see the opening for the check valve brite & clean. Very pleased with result. Also have two observations. First is the washer which separates the check valve spring from the larger escape valve spring. The one in my rifle is solidly fixed and do not believe it is removable. Second is the presence (or not) of the forward lead valve seal. Was told these rifles only had the one seal (it came away with rear end of valve when I pulled it free). Will take another look tomorrow and probe with some pics to ascertain if it is there or not (and remove if the former)...
 
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Good that you got the crud removed, amazing how much glop can be inside older guns - a couple notes to your latest post #25:
- Your post #12 shows the two springs, washer that goes between, and check valve all removed from your gun. If it were stuck in the gun you would not have removed the check valve & smaller spring (see WC's post #16 for the stack of parts as they live in the gun).
- Unless someone worked on your gun and left out the valve-body seal, it should have one. Streaks were never built without a seal at this location. As mentioned previously, the gray object you mention looking like plastic, is likely the original lead seal.

Don R.
 
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Not sure what you mean when you said the washer is solidly fixed and nont removeable? You mean stuck to the springs?? Didnt I see a picture of all the parts you got out?? It should be a seperate piece between the 2 springs . YEs there should be a new seal at the front of the valve guide body AND a seal at the end of the valve guide body . I like using the white delrin or teflon seal types that MAC 1 uses.
 
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Where to begin...DonR & cvarcher: Referencing post #12, order of parts as they came away were:
Round brass valve retaining nut--lead seal--valve--then small brass washer--then the long escape valve (so washer was between small opening at forward end of valve body and held by rear side of escape valve & shaft). Then I saw and removed the large spring which engaged with the brass head of escape valve. With a few bonks the small check valve spring fell out. All which remained was the small check valve itself (residue near and behind the pump hole inhibited it until breaking free). No washer ever came out other than the small brass one. However, looking past the forward end of that brass insert in the air chamber, there is what appears to be a washer-like spacer about a inch or so from forward end. The small spring had to come out of the hole in it to the rear. It also has scuff markings on rear... approximating the O.D. of the larger end of the big spring, which would press against it. I tapped the cleaning rod against the washer (maybe "spacer" would be a better term) several times but it was solid.

Now, in looking for the forward valve seal, I don't think there ever was one. Reason is have seen photos of "picked" lead seals. Where that forward one should be, I used several pics, pointed rods, etc. If there were any degree of lead there, I should have seen impressions, curls, or perhaps lifted a piece from the rim. All it resulted in were small scratch/scuff markings. So, took cvarcher's advice and found I had a foot long wooden dowel measuring .760 in. Then a flat head, very coarse thread 5/8 in. long screw and two washers (.735 in. OD & .230 in. ID). Next I chucked up the dowel in the lathe, used a parting tool to cut the end plumb, drilled out the hole for screw and subsequently threaded it by waxing and turning the screw down completely.

Next was the search for a mild abrasive and discovered those small sanding discs used with DREMEL tools, etc. were .740 in. OD... perfectamundo! Then laid the discs on a soft pine block and placed a washer over the disc... lining it up. Used a 5/32 gasket punch and cut a hole in each disc. Lastly, took screw--disc--washer and fastened them to the end of the dowel. Slid perfectly into place and with little pressure cleaned that area where the forward seal should go. Result was no evidence of lead was found on the disc or anywhere else. The effort just removed any small scratches or scuffs at that juncture. In the first photo viewing down into the rear of the pump tube, you see the rear lip where the rear seal was and further down the forward one... now shiny. Think I am ready to put it all back together, soon as my replacement lead seal arrives (giving me two new ones).

Lastly, found the secret to seeing down into the pump tube. Forgot I had a couple high intensity lab lights (the one pictured came out of a estate sale dumpster). With a adjustable arm and lamp, can arc it over a table top aimed at open end of the pump tube and get a pretty good view right down to the check valve. BTW, photo of dowel head complete was taken after I used it. More to come...Stay Tuned!

Pre-63 Sh BS from rear 1.JPG


Pre-63 Sh BS from rear 2.JPG


Dowel Stick Mod 1.JPG


Dowel Stick Mod 2.JPG


High Illumination Lab Lamp.JPG
 
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I am lost when you describe some of these findings. So why not start from scratch. It looks like you have it all cleaned up inside now. OK. First drop in the intake check seal (little round brass disk with the rubber side down towards the front of the gun. Then drop in the little intake spring. Then drop in the brass washer. Then drop in the larger exhaust valve spring with the narrow end up towards you or the back of the gun. OK now if I remember correctly , you use that square tool to hold onto the rest of the parts and slip it in horizontally and as centered as you can. When you feel the cushion of the spring while pressing slightly you can now turn the gun vertical and press down as far enough so that the end nut will engage with the threads. You will turn the tool alittle bit feeling ever so carefully for those threads to engage. And screw it down locking it in fairly tight. On that tool will be the exhaust valve inserted into the valve guide body. The new lead seal on the back end of the valve body (facing in towards the front of the gun. And the 2nd seal goes between the lock nut and the other side of the valve guide body facing up towards you. I wish someone would have video taped this assembly on youtube.
When a pump compresses the air in the pump tube chamber it goes thru the port hole backing the spring loaded intake check valve to let the air into the compression chamber. The spring closes the check valve . another pump and again the intake check valve backs into the compression chamber only to re turn to closed by the intake spring. Thats how that works. Then when you depress the trigger, a solid steel hammer block is thrust forward by its hammer spring striking the exhaust valve which is held closed by the larger exhaust valve spring. It overcomes that spring pressure and the air pressure thats stored just for a fraction of a second lifting the exhaust valve seal off the valve guide bodys seat rushes out. This allows air to rush up thru the ports of the valve guide body (4 ports) which rush up thru the barrels port behind the pellet. Sometimes there can be a burr on the top edge of that barrel port causing bad groups. Easy way to see is to load a pellet and then fire it out into rags with one pump. Carefully looking close at the pellets rear skirt and front shoulder you should only see 6 indent marks from the rifling . If theres any smears or other guages that could be caused by a burr . With a slotted cleaning rod and a bit of fine grit sandpaper with the bolt completely out of the gun you can smooth out that air port with the cleaning tip twisting it back and forth but dont go too deep as to mess with the barrels rifling , then retest with a new pellet ,one pump into the rags. a decent Sheridan and good eyes at 10 yards you should group 5 shots into a 1/4" circle. Benched of course.
 
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A few more observations:
- If your brass washer was BEHIND the large spring, someone worked on your gun and put it back together improperly - the washer goes between the two springs (ref post #16). Improper assembly could also account for your not finding a forward valve seal...and for the gun leaking in the first place.
- I agree with cvarcher that you could put it together as he describes and be ready to go - don't forget to polish the intake and exhaust valve seats to avoid leakage.
- On one point I disagree with cvarcher: Your older valve likely has a tiny tab to orient its single outlet port properly - make sure that is lined up with its corresponding slot in the gun as you slide the valve parts into place, otherwise all will bind up and not allow you to push everything together.
- If you find that rear lead washer to be a nuisance, it definitely is not required for the gun to work just fine.

Don R.
 
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+1 on everything DonR stated above with one added mention.
Before reassembly, perform a test run with the valve nut alone to ensure it threads in smoothly. Occasionally, lead fragments can lodge in the threads and cause problems. Begin by turning the nut counterclockwise until you feel it click into a thread, then switch to turning it clockwise. If it feels unusually tight, stop and restart from the beginning; you want to avoid a cross threading situation. Use the same technique during actual assembly.
 
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Thanks for the schematic... Very Helpful as have been everyone's comments as well! Yesterday had time to look closely at the original components and attached two photos of the entire train... as they came out of the rifle and as I think they should be (?). This excludes any new/replacement parts. In the first photo, and from trace markings on it, the small brass washer was originally spaced as seen in the second photo. The small, domed head on exhaust valve is way too small to support that spring alone. Note large spring in photos below has a only a very slight taper to it and is fairly strong. However, the brass washer fits perfectly on top of the domed head. Wear markings indicate that is where it was until assembled incorrectly. In the first photo, it was placed behind the domed/rimmed head and this prevented the exhaust valve to seat properly (and cause of air leak out the exhaust port). The other issue was the singular lead seal, which (if only one was used) should have been at the forward end of valve body (photo 2). Also explains why it was not damaged as tapered valve locking nut seated on the rear face of valve as hole in seal was wider than it was. Undoubtedly, another error in reassembly. ON the other hand, because of this, rifle was put away for decades until sold at a garage sale... remaining in fine condition all the while.

OK, a few more things. The new replacement valve (seen in post #12, pics 2 & 3 Center ExV). has too small a pin head. The largest, NOS one is from a later C-Series rebuild kit. Was thinking I can make another brass washer to fix the small-pin one and make it like the original one or just install it as made. Probably could make a brass shim to press over the brass pin head as well to make it wider. Was a "no returns" on the parts I got, so don't want to waste them. Regarding the valve body, it has four exit ports in it, so orientation would not be a issue (?). Regarding part #347 (spacer washer for springs), this is what I see inside but does not move. Maybe it was intended that way, as I would not be using the small brass washer as well (unless it was meant to fit perfectly in the center hole of #347)... thoughts...

Pre-63 ShBS Comps as Removed.JPG


Pre-63 ShBS Comps as Should Be.JPG
 
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ok, first of all forget about where this washer was. It belongs between the 2 springs--period. Not ever on the back of that exhaust valve body. Number two forget about how small the nipple on the exhaust valve head is to fit into the exhaust valve spring . When its all inside it will stay centered . Its really quite easy and a sheridan handbook showing the parts diagram will show all this. You could search for an exhasut valve stem that does have the larger diamter nipple ,im sure they are out there. Check with Rick Willnecker in Penn. he has all the parts . Not sure if his website is on or off. I think it was called Precision pellet.
 
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+1 to Wadcutter's post #32 and cvarcher's post #36, including the fact that the small nipple valve will work fine without messing with it.
> Please believe us, your brass washer IS part #347 and DOES go between the springs. If that washer were stuck in the gun, you would not have been able to remove the small spring nor the inlet valve.

I think we all hope you will reassemble the gun and enjoy it.

Don R.
 
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