Thanks to this channel I can repair my 490 instead of buying a new one. I need to repack the pump, clean or replace the prime valve and the sprayer won’t shut off with the on/off switch maybe it’s something electrical
Hey Saul, thanks for the great comment! That's awesome to hear that you can repair your Graco 490. Definitely a lot better than replacing! It could just be a faulty switch. You can replace these separately as well. Refer to this repair manual for some extra help: (AUS VERSION) www.graco.com/content/dam/graco/tech_documents/manuals/3A6/3A6491/3A6491EN-K.pdf Hope this helps! 🙌
I just repacked my Graco 395st but it won't prime. I followed the instructions meticulously. This is the 3rd time I've repacked it in 20 yrs and I have tons of pictures and notes so I know what I'm doing. It's got a new piston too. The cylinder is in good shape. Hoses are clear, no obstructions. Any ideas?
Hey, great question! What we normally do is is test in sections so we can try and isolate where the issue might be. I recommend unscrewing the hose at the back of the pump and trying to prime the unit. If you don't get any water flowing through then you know that the issue must be somewhere between the strainer, suction tube and pump. If it is something in the pump, the most likely thing is a missing or busted O-Ring, ball or seal.
What did you mean when you said building pressure but not stalling ? I have a GX19 that goes full pressure as soon as the pressure knob hits the Green Rac X section, Does not shut off and flips the Prime Valve from Spray position back to Prime. Any ideas of the issue ?
Hey quick question.. do you need to adjust the brass part of the valve by tightening or loosening it? My new valve came with it only halfway screwed down. Thank you 🙏
Hey mate, Usually this comes from the factory already tightened up. If you can see the thread below the brass fitting where it screws into the stainless section then I would recommend tightening it until it sits flush. If you have any issues after installing I would contact the place of purchase and get them to swap it out. Hope this helps!
My 595 is having an issue currently(on the past 2 jobs, 2 weeks) where on first use of the spray gun, regardless of where I put the pressure gauge be it low 1k psi to 2k psi the pressure will just keep going up non stop and basically bounce off of 4000psi like a car hitting the limiter until I begin spraying a few rooms. I found that quickly just spraying out a few rooms ceilings at the major pressure its at, normally 2 bedrooms is enough, that it will go back to normal and build and hold pressure at the amount I want and I am then able to adjust it properly as it then maintains the correct pressure. So it could be some shit built up in this valve that's causing it? and as it heats up I guess the tolerance changes and allows it to work as intended.
I have a Graco 395 finish pro. When I switch the valve to pressurize, I feel air blowing out from the valve and I have to push the valve in to stop the air from coming out. Then the rig pressurizes. Does it need a new prime valve? Thank you
Sprayed 74 of 80gal...last 2-3 i dropped from 2200psi to fluctuating 1000. Shut down for the day. Afrer flushing my rig, i noticed an excessive amount of water in my prime bucket. 3 gallons of product! I cleaned a rough Valve drain. Rig pumps up to and holds 950. Turning the knob up, it fails. Transducer? Has anybody seen product thrown back through prime valve? GRACO 695 ultra max
Thanks to this channel I can repair my 490 instead of buying a new one. I need to repack the pump, clean or replace the prime valve and the sprayer won’t shut off with the on/off switch maybe it’s something electrical
Hey Saul, thanks for the great comment! That's awesome to hear that you can repair your Graco 490. Definitely a lot better than replacing! It could just be a faulty switch. You can replace these separately as well.
Refer to this repair manual for some extra help: (AUS VERSION)
www.graco.com/content/dam/graco/tech_documents/manuals/3A6/3A6491/3A6491EN-K.pdf
Hope this helps! 🙌
Very informative and well put together video Thanks for sharing
Thanks so much. You've saved me 125 bucks
Glad to hear! That's the aim of the game 🙌🏼
I just repacked my Graco 395st but it won't prime. I followed the instructions meticulously. This is the 3rd time I've repacked it in 20 yrs and I have tons of pictures and notes so I know what I'm doing. It's got a new piston too. The cylinder is in good shape. Hoses are clear, no obstructions. Any ideas?
Hey, great question! What we normally do is is test in sections so we can try and isolate where the issue might be. I recommend unscrewing the hose at the back of the pump and trying to prime the unit. If you don't get any water flowing through then you know that the issue must be somewhere between the strainer, suction tube and pump.
If it is something in the pump, the most likely thing is a missing or busted O-Ring, ball or seal.
What did you mean when you said building pressure but not stalling ? I have a GX19 that goes full pressure as soon as the pressure knob hits the Green Rac X section, Does not shut off and flips the Prime Valve from Spray position back to Prime. Any ideas of the issue ?
Hey quick question.. do you need to adjust the brass part of the valve by tightening or loosening it? My new valve came with it only halfway screwed down.
Thank you 🙏
Hey mate,
Usually this comes from the factory already tightened up. If you can see the thread below the brass fitting where it screws into the stainless section then I would recommend tightening it until it sits flush. If you have any issues after installing I would contact the place of purchase and get them to swap it out.
Hope this helps!
@@GOIndustrial thank you much appreciated, I ordered a new one; should be here today’s
My 595 is having an issue currently(on the past 2 jobs, 2 weeks) where on first use of the spray gun, regardless of where I put the pressure gauge be it low 1k psi to 2k psi the pressure will just keep going up non stop and basically bounce off of 4000psi like a car hitting the limiter until I begin spraying a few rooms.
I found that quickly just spraying out a few rooms ceilings at the major pressure its at, normally 2 bedrooms is enough, that it will go back to normal and build and hold pressure at the amount I want and I am then able to adjust it properly as it then maintains the correct pressure.
So it could be some shit built up in this valve that's causing it? and as it heats up I guess the tolerance changes and allows it to work as intended.
Thanks
No problem! 🙌
Hi have u got any ideas the size of the small O ring at the needle? My o ring broke 😢
I have a Graco 395 finish pro. When I switch the valve to pressurize, I feel air blowing out from the valve and I have to push the valve in to stop the air from coming out. Then the rig pressurizes. Does it need a new prime valve? Thank you
Hi Josh, great comment! You are 100% spot on there, It sounds like a worn prime valve.
Sprayed 74 of 80gal...last 2-3 i dropped from 2200psi to fluctuating 1000. Shut down for the day. Afrer flushing my rig, i noticed an excessive amount of water in my prime bucket. 3 gallons of product! I cleaned a rough Valve drain. Rig pumps up to and holds 950. Turning the knob up, it fails. Transducer? Has anybody seen product thrown back through prime valve? GRACO 695 ultra max