JGA spray gun help

[catchawave]

Hi all,
Just bought a used Devilbis JGA suction gun off ebay, but when I connect to my airline, air just streams out of the air can and th trigger does nothing to stop this.

Is this right or has it got seal problems or something.

Any help and feedback is welcome. I am new to spraying 2k and have been scanning this site and others for info.

I bought the gun as I now need to put the top caot on my 74 bug.

Cheers,
Andy

 

[pedrobedro]

Put some fluid in the can and see if it sprays it out, is the trigger spring returning the trigger ?. There are two stages, one where just air comes out and then where fluid is released and no it shouldn't do it as no air should pass through till you pull the trigger.

 

[jaykay]

might of been sitting awhile,there should be a seal on the top,betweencup and the base.it should be leather or a polystyrene one.
keep us informed.

 

[jaykay]

oh check vent hole is not blocked up. that is in the top of base that fit to the cup/pot.

 

[catchawave]

Jga.

Sorry guys,

I meant to say that air just streams out of the air cap.

When I pull the trigger the fluid does come out ok but the air is just on all the time.

Andy

 

[Wozzaaah]

Isn't that known as a 'constant bleed' gun?
The air is on all the time, the trigger just controls the paint flow?

 

[brightspark]

Isn't that known as a 'constant bleed' gun?
The air is on all the time, the trigger just controls the paint flow?

its either one o them but i didnt think devilbiss made them . u said its a jga there was an exploded view of one in a post on here a few weeks ago sumeone might know where it is .could be summat worn on it letting the air though

 

[catchawave]

jga help

Hi,

I have got the exploded diagrams and it shows a needle valve to control air flow and one to control paint flow so I dont think that air should be coming out all the time.

Also, The air control screw can be tightened up and the air stops but no paint can be sprayed either.

Seems to me that the valve or seal that the trigger controls isnt working but when the trigger is squeezed the paint will spray out as it operates the top lever.

I am still trying to contact the guy who I bought it from as he said it was working 100%.

He could have done me but hopefully not.
Andy

 

[brightspark]

Hi,

I have got the exploded diagrams and it shows a needle valve to control air flow and one to control paint flow so I dont think that air should be coming out all the time.

Also, The air control screw can be tightened up and the air stops but no paint can be sprayed either.

Seems to me that the valve or seal that the trigger controls isnt working but when the trigger is squeezed the paint will spray out as it operates the top lever.

I am still trying to contact the guy who I bought it from as he said it was working 100%.

He could have done me but hopefully not.
Andy

at worst there a good gun and u can get the service kits 4 them

 

[danelectro]

JGA isn't a constant bleed gun Wozzah, I think you've probably got a stuck air valve - look behind the trigger, you have the main needle, then below that a sprung loaded air valve, the air valve should NOT be stuck in, it should rest against the trigger. think that is your prob

If you can get a picture put up here of a side view, I could tell you straight off what the problem is

 

[catchawave]

jga gun help

Hi,

Heres a photo of my gun, the trigger is loose sortof indicating the air valve needle is stuck in slightly.

Just to note that when the trigger is not pressed no paint comes out, but air continues to come out of the air cap. When I squeeze the trigger paint / thinners does spray our nicely.

Hope you can help.

Andy

 

[Paul.]

you'll need to take the air needle valve assembly out and investigate, the trigger will need to come off to give you room to withdraw it, it may just be sticking, I've seen sprayguns with rusty springs caused by damp air, all the parts are available, that one looks as if its been apart a few times by the look of the rounded nuts,

 

[Welderpaul]

The trigger rattles on mine. I think they are all like that!

 

[catchawave]

Thanks guys,
I have taken the assembly out including the small rod but the spring and rubber seems to be stuck in there.
Can I just pull it out or will it shaft the gun.

Cheers.
Andy

 

[Paul.]

Gently pull it with some narrow nosed pliers it should come out, sometimes this happens when the gun has been immersed in thinner to clean it. (something you shouldn't do with an assembled gun). thinner and paint debris finds its way into the airways and gums up the works when the thinner evaporates,.

 

[danelectro]

I'm thinking that air valve is stuck, like paul says, gently pull it out and see what's what. Got to say I'm convinced it's not terminal, just a sticky thingy!!!

I do believe the valve and spring should be attached to the shaft, but it's only a push fit so as above it's quite feasible to have some old thinners in there mucking it up

If it helps, I'll pull mine apart so you can see what it looks like, will have to be tomorrow, coz I'm going to bed now!!!

P.S. one thing to check, if you take the fluid needle out (unscrew the fluid flow screw - below the fan control) see if there is any resistance from the air valve against the trigger, basically the trigger should spring back....if that makes sense!!

 

[jaykay]

sounds like it time for a overhaul/rebuild.
air coming out the aircap,sounds like the crush washer behind the nozzle needs renewing.

 

[catchawave]

Jga

Thanks guys for all the help, I really do appreciate it.

I will take it out tonight including the spring and washer and see what happens.

Be interesting to see any photos of your valves just so I can see how it goes together.

Does anyone know how much an overall kit is for a JGA and where to get one, The guy on ebay hasnt got back to me yet.

Still, its meant to try us and all that.

Would like to get the beetle painted by the end of the year...ambitous??

 

[catchawave]

Jga update

Hi all,

Just an update, managed to contact the guy about the gun, I have sent it back to him as he says he has lots of spares and he may be able to repair the problem hopefully.

I did check out the cost of a new one, the FLG range I can get for about 85 quid. Just in case he gives me a refund.

Anyway, just a quick thanks to everyone who helped me out, Thanks again.

Andy.

ps, looks like the weekend paint job is now postponed.

 

[jaykay]

a repair kit 62 quid.
so now this guy has the gun back and your money?????
you should read some of the ebay discussion boards.