My Daisy 747 had only dieseled once before since I bought it in January of 2003... probably in the first year. It sounded more like .22 short than an air pistol, but nothing happened. A month or so ago, it did it again. THIS time with more serious consequences. There was a loud BANG, the bolt blew open, and smoke curled out of the muzzle and now open bolt. I didn't notice anything at first, aside from a small "click" when pumping the handle, but soon, damage became obvious... I took a the usual single pump, and the lever, the piston, and the front sight fell off on the floor. Not good. My toy broke. As it turned out, the front end of the compression tube had cracked, and that was all that was holding the gun together.
Maybe a week later, I found a slightly beat up 717 on ebay for a decent price... Most of the basic mechanics are the same, and replacing the broken compression tube was easy. I was back in business, popping away in my basement, slowly regaining the accuracy I'd lost over the last several years of very little pistol shooting, and much less expensively than firing my powder pistols. But not for long. Soon, the gun quit working again. Opening it up revealed a broken sear... Very likely it had cracked when the bolt blew open, and just took a little while to break. I was able to replace it with the sear from my "parts 717," but while the gun functioned again, I'd lost the ability to adjuist the trigger pressure. This wasn't a big problem... the pressure was at the lightest now, which is OK for a target pistol, but still, it nagged at me, and finding either a new 747 sear or a "parts 747" was more difficult, and most likely expensive.
I was popping away OK now, but the loss of trigger adjustability still nagged at me. It was one of the things aside from the match grade barrel that made my gun a 747. So, I took things apart again, and using a large steel washer, fashioned new flange to engage the trigger-pressure spring and soldered it into place, carefully measuring, comparing, and trying into place to match the broken sear. Taking a torch to my difficult to replace part made me nervous, but things worked out in the end, and my gun now fully functioned like it's supposed to, even though I have the trigger set to touch off lightly.
Daisy insisted in their instructions to use ONLY 20 weight non-detergent motor oil to lubricate the pistol, and I'm a guy that follows instructions. If I bought a new bucket, I'd read the instructions on how to pick it up. I'd suppose they figured that the low pressure, single pump, pistol wouldn't have a dieseling problem. However, I've now acquired a bottle of silicone air gun lubricant, and no combustible product will ever again come into contact with my 747.
And, I'm going to keep an eye out for a "parts 747" just in case...
Maybe a week later, I found a slightly beat up 717 on ebay for a decent price... Most of the basic mechanics are the same, and replacing the broken compression tube was easy. I was back in business, popping away in my basement, slowly regaining the accuracy I'd lost over the last several years of very little pistol shooting, and much less expensively than firing my powder pistols. But not for long. Soon, the gun quit working again. Opening it up revealed a broken sear... Very likely it had cracked when the bolt blew open, and just took a little while to break. I was able to replace it with the sear from my "parts 717," but while the gun functioned again, I'd lost the ability to adjuist the trigger pressure. This wasn't a big problem... the pressure was at the lightest now, which is OK for a target pistol, but still, it nagged at me, and finding either a new 747 sear or a "parts 747" was more difficult, and most likely expensive.
I was popping away OK now, but the loss of trigger adjustability still nagged at me. It was one of the things aside from the match grade barrel that made my gun a 747. So, I took things apart again, and using a large steel washer, fashioned new flange to engage the trigger-pressure spring and soldered it into place, carefully measuring, comparing, and trying into place to match the broken sear. Taking a torch to my difficult to replace part made me nervous, but things worked out in the end, and my gun now fully functioned like it's supposed to, even though I have the trigger set to touch off lightly.
Daisy insisted in their instructions to use ONLY 20 weight non-detergent motor oil to lubricate the pistol, and I'm a guy that follows instructions. If I bought a new bucket, I'd read the instructions on how to pick it up. I'd suppose they figured that the low pressure, single pump, pistol wouldn't have a dieseling problem. However, I've now acquired a bottle of silicone air gun lubricant, and no combustible product will ever again come into contact with my 747.
And, I'm going to keep an eye out for a "parts 747" just in case...
