That's a good challenge to take on, I hope you can getting it shooting again.
Hi,
A friend bought this Sheridan Model B Sporter recently from the USA.
I am going to try to make it work again.
The pump cup doesn't seal in the tube. A friend advised to soak in transmission fluid stop leak.
Hopefully that will work.
I would like to "get into" the valve.
Mostly out of curiosity, but probably because it needs new seals.
There's no info on the net on how to do this.
I guess a special tool is needed to unscrew the valve nut?
Here are a few photos. The gun has seen some life, and I think the barrel blocks have been re-soldered. That might be the reasons why all the paint (B's were painted, A's were chemically blackened) is gone.
Cheers, Louis
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That's a good challenge to take on, I hope you can getting it shooting again.
Nice Sheridan to have Louis - makes me jealous that you can import from the US freely.
You know who to ask if you want the definitive answer on the valve![]()
Hi Louis!UJ will supply a repair manual upon request....Trev
Thank you gents.
I shall indeed contact The King of Seals
@Trevor, good tip, I've sent UJ an email.
The pump cup is soaking in "transmission fluid stop leak". If that doesn't help, then I will try to flare it up.
Although I can't unscrew it. It might be Loctited.
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The valve is out, with thanks to advice from UJ Backus.
I would like to unscrew it, but it's super duper tight.
The logical thing would be to replace the o-ring and then test if it seals, but it would be interesting to "get inside".
Perhaps it needs some heat, and collets.
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sometimes the adage if it ain't broke don't try to fix it springs to mind
but it doesn't look a difficult part to make
I asked UJ about disassembling the valve, and he confirms that they sometimes need a lot of heat, and a lot of force.
The factory used a tough thread sealing compound.
I will have to leave this one closed until I know if it works.
Otherwise I will get the propane torch out![]()
Thank you Lawrie.
The valve is really super tight. I am using collets, but there is zero movement, even if I use all the force I have (admittedly, not a huge amount, but still).
I have decided to leave it. It would be good to at least clean, or better: resurface or replace, the two seals inside. As the inlet valve seems to leak (air pressure is felt on opening the pump arm, from 5 pumps onwards).
The pump cup seals well, after a few "sessions" in the spring compressor.
I am now getting 620 ft/s with 13.73 gr JSB, at 8 pumps. It could be a bit better (my A does 13 ft/lbs on 8 pumps), but it ain't bad.
I will call this project finished for the time being. It will make its way to the owner, my friend in the North of Holland (which in our country means a two hour drive; we think that's very far)
This quad seal off a TR Robb custom Innova pump head (which was rubbish tbh) fits, hooray!
Nice barrel
This was a special moment, when the valve re-entered the gun
I like looking at the gun from every angle
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Well done Louis. It does look like a solid piece of engineering.
Cheers ratbuster2240.
It needs more work, both mechanically as comsetically, but I'll leave that to the owner.
I have put the gun "on the rails", it shoots now, that's nice.
I shot my A during the weekend.
On Saturday evening it performed well; a 2 cm group at 30 meters.
At 8 pumps (I thought 13 ft/lbs, but it's 14; 680 ft/s).
But on Sunday, the pellets hit low, and there was less of a BANG.
Tested, power low.
Listened at the valve after pumping; a leak from the inlet.
I guess I'll have to take it apart and kindly ask Lawrie to make new seals
Cheers
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That's very healthy power for an 80 year old airgun. Will you use a polyurethane material for the inlet seal?
Yes it packs a punch and it's very accurate too. The sights are great, better than on the B actually (finer foresight).
I think that Lawrie uses polyurethane yes. Hope I will get this A valve apart! It was resealed in 2010 in the USA.
Cheers, Louis
Ps. I know it's sinful but I think I prefer this cheap Crosman 187, shooting wise. 40 shots per powerlet at 620 ft/s, and very accurate. Wish it had grooves for a scope.
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