[workingjoe]

i bought the o-ring kit. the gun was removed from the job after it would auto shoot when plugged in and it seemed there was something sliding around i the gun holding it pointing up or pointing down before plugged in to air. soetimes when plugged in to air it would just leak out then replugged in sometimes it would seat" and hold pressure to allow use. i took it apart.. cleaned it . reinstalled it all teh o rings looked fine no scrathes or nothing but loads of oil and grime in teh inside of gun. it is still shooting a nail when plugged in . maybe i shoudl rebuild the trigger valve . this is my firs nail gun rebuild so any help is appreciated.

 

[The Coastal Craftsman]

See if you can find a rebuild guide on line for your model. Should be an easy fix. But def dont be using it if it's randomly letting nails fire. Sounds like the trigger valve may be faulty or needs cleaning out. Try spraying some brake and clucth cleaner down inside the air inlet then give the the tool a few blank shots. If it works fine then re oil the tool with air tool oil and see how it runs.

 

[JonM]

i bought the o-ring kit. the gun was removed from the job after it would auto shoot when plugged in and it seemed there was something sliding around i the gun holding it pointing up or pointing down before plugged in to air. soetimes when plugged in to air it would just leak out then replugged in sometimes it would seat" and hold pressure to allow use. i took it apart.. cleaned it . reinstalled it all teh o rings looked fine no scrathes or nothing but loads of oil and grime in teh inside of gun. it is still shooting a nail when plugged in . maybe i shoudl rebuild the trigger valve . this is my firs nail gun rebuild so any help is appreciated.

bostitch is notorious for leaking at the trigger....

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[Kent Whitten]

I think I would be wary of using cleaners inside of the air nozzle. Some of those cleaners will melt the rubber o-rings inside rendering it completely useless. I know some are fine, but not all are created equal.

 

[The Coastal Craftsman]

Brake and clutch cleaner should be fine as it's brake seal and clucth seal freindly. But read on the rear of the can before you use it to see if it says it reacts with plastic or rubber.

 

[willworkforbeer]

Saw this thread and dropped in to make a point. Anyone inclined to work on or offer advice on nailgun repair that is not an ASE certified mechanic could be called a hack. And nailguns are dangerous right?

I was an ASE certified GM mechanic (over 20 years ago), I saw my fair share of shade tree hackery. Stuff butchered and yes even sometimes dangerous.

My point is the next time those of you who are inclined to attack someone for being a hack think about it for a second first. Hey I've done it here myself. Its getting pretty freakin vicious though.

Some of you guys feel entitled to big money, now its you invading the handymans territory, not always the other way around. Times are tough, there isnt enough work for everybody. Chill out a little :thumbsup:

 

[workingjoe]

ok i pushed out the rolled pins. pulled teh valve out it looks pretty clean and ok.. cleaned it off blew through it and put back together . still shoots off a round when hooked to air.. i dunno maybe i will do the o rings and then put it back together see if that helps maybe they are damaged and causing this.

 

[Tom Struble]

it could be the trigger valve body itself i always replace the whole assembly on those

 

[Andrew M.]

it could be the trigger valve body itself i always replace the whole assembly on those

I have senco clone I just rebuilt, older Heavy Duty 15ga DA finish nailer, metal build and the trigger valve was the issue. I rebuilt it with new orings and polished the brass piston bore[had some scratches] on the valve with Blue magic and a Q-tip.. No issues now. It would also shoot a nail when a hose was put on. Your trigger also must be free to move and not have the trigger piston touch when air is on. There is usually an external spring on a restrictive trigger that holds it away from the piston/valve. Use of the wrong oil or too much causes problems. Marvel mystery oil is a good oil if you want to clean out the gun as it has solvents and will not harm plastics/rubber. Snap On uses that for their air tool oil.
Just bought a Bostich coil siding siding nailer, and not impressed with all the plastic parts. Saves weight but at a cost. Wish I bought a Hitachi , it has a better build, the older light green ones I mean. My NR90AC3 is excellent for example.

I would buy a new valve. Hate all those cheap plastic parts, the pic looks like a plastic assembly. Hold any gun away from you when you click on the hose, you never know.