Hello All,
So i picked up the super tune kit from hajimoto. While stripped down I super polished the bolt and other moving parts using high speed soft wire wheel, then buffing compound and a buffer. Incredibly smooth action now. So that's cool. However after reassembly I find that attaching the air bottle air poured from the barrel. I disassembled and followed the instructional video again. Success. Not so fast. Over night the tank went from 1500psi to 0. Pumping air does nothing while bottle's on the gun. Remove bottle and fill no problem. Reintroduce bottle and there's a short burst leak then it sealed. Left for 2 hours and it drops 500psi.
Any ideas?
Thank You,
John
@pluric Yep, he and I spoke before he shipped my order. Very knowledgeable and friendly guy, but I know he's super busy right now. I did email him I just figured while I was waiting on him to have a moment that maybe someone here had run into a similar situation. New air compressor arriving tomorrow!! I've hand pumped maybe 10 tanks worth in two days. lol shoulders dead.
Then my guess would be that o-ring that is so easy to nick pushing the valve back into the tube video 16.36. Fortunately I had ordered a replacement kit with the tune kit. I tried to be careful but I did need to replace it. Also did you seat the poppit as in the video at 15.34? Also tighten the valve to swell the o-ring?
@pluric I lubed every o-ring with lithium oil. I can't say definitively but i don't think i nicked one. I did do the burnish but may not have gotten it good enough. I can do it again if we think that's the issue. Could it be? I did tighten the valve cage to squish the o-ring until the threads stopped me from tightening any more.
So what do you think? Should I pull it all apart again, replace all the o-rings and re-burnish? Once burnished, should you be able to see evidence on the poppet? He said not to melt it so I did the 10 seconds he mentioned.
Thanks,
John
ok. after watching that burnishing part again (for the 10th time) he does specify 'to prevent leaking air when under pressure'. So I'm probably going to be re-burnishing tomorrow. Also both times that I've not been able to add air while the bottle was attached - the bottle was completely empty. Both times putting air in the bottle and then attaching to rifle seems to resolve the issue. Is this typical?
Reburnish your poppet. That is most likely it, make sure both surfaces are super clean and then burnish.
When I burnish a poppet on a valve I bring my lathe to 2500rpm and put 5+ pounds of force for 5-10 seconds squishing the parts together to get a really good burnish. I do that three or so times then inspect the poppet to make sure it has a good solid burnish.
Handpumping a n empty bottle on gun is tough to get poppit to seat- it will leak thru barrel- or try cocking first, taking pressure off valve pin(once you have compressor, shouldn't be a problem)- as far as your slow leak currently, I would look @ bottle block o-rings(need to deburr block screw holes as they will nick the block o-rings & are rough from the factory)- I've done both my .22 & .25 & had to do the block rings 4 times before getting it right. A tiny nick is all it takes to get slow leak.
ok. after watching that burnishing part again (for the 10th time) he does specify 'to prevent leaking air when under pressure'. So I'm probably going to be re-burnishing tomorrow. Also both times that I've not been able to add air while the bottle was attached - the bottle was completely empty. Both times putting air in the bottle and then attaching to rifle seems to resolve the issue. Is this typical?
First I'd see if you could talk to Hajimoto. That is so much work to tear it down again. The poppit would be suspect. On your bottle fill question I think a slow fill, by hand pump, could be part of the issue. Sometimes valves, poppits what ever is being sealed by pressure need a good "shock" of instant high pressure to force them to seal. Often my hose fitting from my air tank to my fill valve leaks until it gets enough hose pressure to force it to seal.
So if for example if I'd been using a hand pump I don' think I'd ever be able to get it to stop leaking enough to build pressure to seal itself.
I've got a couple Gauntlets with the Hajimoto kits on them. I just went and looked at the pressure and they both are holding. One I purchased with the kit installed the other one I did myself. So I am curious what may be the cause of your air loss.
Rick
I am suspecting the poppit and will likely re-burnish before the day's end. Tear down and reassembly is really not a big deal. I can have it done carefully in under an hour. Just checked gauge... it's on zero. So i'll reburnish and post back.
Thanks everyone for chiming in.
John
**EDIT UPDATE**
Started tear down at 2:16pm, re-burnished and test fired at 2:40pm. No leaks, can fill empty bottle attached to rifle with hand pump from 0psi. Thanks again to all who chimed in.
So I have put the compressor together and have returned home with two gallons of oil when i needed just 12 oz. So ready to shoot! There are a herd of about 10 deer all around my 35 and 75 yard targets. LOL. squirrel too. quite a few of them. and so I wait. Loving my new hung feng compressor though. turned 45 minutes of manual labor into a button press followed by a one minute wait. sweet!
@pluric That's too funny. I'm just over a week. I'll keep the hand pump as backup, but the compressor is amazing. And yes it is holding air now. I just didn't burnish enough. I didn't want to over do it. Guess that's what happens... air leaks. LOL. Thanks again!
John
@pluric-I followed your same path LOL discovery+pump & now 3 compressors later, all is good(with 10+ PCP's to fill)
I'm sure there are several members here that have been that path. ? Once you've made the decision to shoot with air it's awful hard to look at a pump and think "This will be fun". Walking around pesting is one thing, but to try and paper shoot, no way. I've gotten so lazy I'll often tether the gun so I don't have to fill it. ? ?
I bought a Daystate to leave at my vacation spot so I don't have to haul tanks back and forth. If I could just find someone to aim and pull the trigger I'd be set. ?