Thursday, December 17, 2009

Daisy 717 Repair Part 1

Nick sent me a big box of incredible airgun fun today. He's got some kind of secret gift for finding airgun stuff at yard sales, flea markets and gun shows that most of us can only dream about. In the box was a Daisy 717 target pistol. It was in several pieces. A quick reassembly and I found--as I had been forewarned--that the air valve was leaking like mad. Long time and extremely astute readers will note that Nick has already repaired the .22 cal version of this gun--the discontinued model 722. I thought I'd blog this anyway. I know, aways late to the party. Bear with me. The generic term 7XX is used to denote all the variants--the 717, 747 and the discontinued models 777 and 722.

Daisy 717. Age unknown.

If you've never handled a Daisy 7XX pistol, take a look at that ruler. It's about 14" long. Target guns can be almost cartoonish in size.

I began disassembly by removing the rear sight and setting it aside. Next, put the safety on by pushing it all the way to the right--or the ball bearing and spring will fly across the room. Ask me how I know this.

Then unscrew the grips.

Open the cocking lever,

and remove the three phillips head screws.

The left cover lifts right off.

The grip frame then pulls off and the compression tube comes off the front.

Wrap your hand around the left side of the safety and push it from right to left. The ball bearing and spring will pop out of the body of the safety button.

Give the cocking lever a quick close and the air valve and barrel assembly will "pop" out of the end of the compression tube from the pressure build up. If the pump seal is bad and it won't build pressure, just pull it straight out.

This o-ring seals the face of the valve to the inside of the compression tube so the compressed air goes into the valve instead of leaking around it.

Unscrew the pump lever pivot.

A curved washer is under the screw head.

Front sight lifts up. It's got a post that slides through a bushing for the cocking lever pivot. The post is threaded for the pivot screw removed above.

The steel cocking lever bushing. Note that is has a groove on the top end. The groove must sit at exactly 90 degrees to the tube when reinstalled. The bottom of the front sight has a corresponding notch that rests in this groove--this aligns the barrel to the compression tube.

Pulling the cocking lever forward removes the piston. There are two curved washers . One above and one under the cocking lever. The curved sides match the ID of the compression tube. They keep the lever centered at the pivot. The cylindrical bushing goes through it all.

Piston has an o-ring seal and a felt wiper. The felt (replaced with a foam ring on the new models) retains oil. It's only there to keep the seals wet with oil to prolong sealing and lifespan.

Fear not. The new foam ring Daisy now uses will retrofit perfectly.



Remembering Nick's previous experiment, I faced off the front of the piston using the Taig lathe. Removed several thousandths until the face was even and the high spots were gone.

High speed, a sharp knife, and light cuts.

LinkLapped the face with polishing compound on a granite plate. The spots in the center are low spots--small imperfections in the face of the casting.

Removed the valve with a 1/2" wrench.

Shoot. It's an early one. The valve seal is conical on the early guns.



The original on the left. A brand new 7XX valve is on the right. The white end seals are different shapes. The new seal is dome shaped. I don't know if the new seal is simply a drop-in replacement or if the seal needs to be turned down into a cone.

More to come...

17 comments:

Anonymous said...

This is Great !
I have had my Daisy 717 for at least 30 years with no problem. Now the seal on the piston has gone and I have to take it apart to replace it.
I have a problem with getting the barrel separated from the air chamber. I can see the shaft attached to the front sight and this stops te piston from sliding out the front. But I can't get the back end off. I tried tapping the barrel backwards but it only moves slightly. Is there something else holding It?

Felice Luftschein said...

I don't think anything else is holding it, it should come out if you pump the lever.

Anonymous said...

Pumping the lever did not work as the piston seal had gone but I found a brass rod and gently tapped the barrel at the muzzle. After it moved about 1/4" it came free. I looked at the mating of the two surfaces - the piston and valve and at first they appeared flat, then I discovered a thin film, almost paperlike that may have been accumulated dried residue of oils. I remember one time, for storage purposes I used a Teflon oil so this might be what it is. I'll replace all the seals and anything else I can think of.
By the way there is a version of this pistol with a Walther bbl. still being sold. I got one from Kittery Trading Post in Maine

Thanks for your excellent article and photos.

Anonymous said...

Hi, me again. I got two sets of O rings and a new valve from Daisy. Fitted them and re-assembled, but the back seal won't hold pressure. I don't know about the front seal but I can hear the air coming out the back seal as I close the lever. Different O rings don't help. I tried with the new valve and the old one and with and without the trigger assembly. Any ideas?

Anonymous said...

Use soapy water to determine exactly where it is leaking?

Without knowing exactly how it's leaking it's hard to figure out. Could be a crack, a rough spot in the tube, etc. I'm assuming you have it cocked when you are testing?

Nick

derrick38 said...

Leaking 717,

Did you read part 3? Note the shims I made.
http://anotherairgunblog.blogspot.com/2009/12/daisy-717-repair-part-3-final.html

I think you may have the same problem that plagued my gun.

Anonymous said...

Thanks everyone. I did two things and it seems fixed. The first was when I assembled it I really pushed the valve assembly into the tube. There was enough retention of compressed air to drive a pellet out immediately. But 5 seconds later it was gone. However, oiling fixed that. So I agree with derrick38 on the amount the assembly has to be forward. I wonder how plumbing Teflon tape would work instead of shims. Might not be permanent, though. Thanks again. Bren

derrick38 said...

I think you underestimate how easy the shims are to make. Some $3 scissors and a pop can would do it. I think I eventually glued them in place after confirming it was a successful repair.

Anonymous said...

hey can anyone help me ive got a 717 but the plastic lever on the bolt action has snapped cant seem to find spares for sale are they available it was my first airgun and i really want to get it fixed

Nick Carter said...

Fill out the form here:
http://daisy.com/serviceform.html
Daisy will send you an exploded view and price list of all the parts for the 717.

Technoshaman said...

Thank you for all the information on the 717, they are really helpful. I've had mine since I was 14 (19 years since then). It's been leaking big time (I'd left it at my dad's and now my love for air pistols / rifles is back) and the rear sight is gone. I'm about to order the spares from Daisy. And yes, my safety spring and ball bearing flew away as well since I found your site "after" disassembling my 717 :)

Anonymous said...

Where do you get the new valves from I've been looking but I can't find any?

derrick38 said...

Direct from Daisy

Anonymous said...

I have a 717, and just found out someone broke off one of the ears on the rear sight, what/where do I look for a replacement rear sight?
Also, I had a point sight 800 and one of the dove tails are broke, (plastic)I'd like to replace it with another scope, again..what/where do I look for a new scope?
I've tried amazon, ebay to no luck, any help would be appreciated.
If anyone has any suggestions, please email me at:robhec@ptd.net as I don't usually come to this site.
Thank you...Bob

Felice Luftschein said...

Bob,
http://www.daisy.com/customerserviceform

And they'll let you buy replacement parts.

Peter Pan said...

Hi, I'm from Germany. my english is bad. I need for 717 daysi a complete rear sight assembly. who can help! Norbi from Germany
Email: norbert.golf.kuehn@web.de

Peter Pan said...

Hi, I'm from Germany. my english is bad. I need for 717 daysi a complete rear sight assembly. who can help! Norbi from Germany
Email norbert.golf.kuehn@web.de