I bought an old Graco 395 pro series airless sprayer. I does work well when I tested with water but taking the filters out and intake screen off I noticed someone didn't clean the unit very well and has cured paint in the intake tube. Rest of it has diluted paint cured inside like it was rinsed but not long enough. Anyhow I got all the filters cleaned but wonder what else I can do for it. If anyone knows, I want to use it for oil treatments to maintain my log house. Thanks anyone.

I would pour a bit of paint stripper in the plugged up areas and work with it. I would be careful some paint strippers can and will damage rubber o-rings.

thank you, Currently using 'Krud Cutter that dissolves latex. It's getting the filters and screens clean. Soaking the gun right now. Looks like oil based paint was used one time, thankfully, got that removed from the pick up tube screen by poking a wire brush thru the screen. I'm going for a new hose tomorrow and it does have a new tip thankfully.

 

Paint store said it's probably best not to run anything thru it that dissolves paint as it may cause a lot of clogs in the future. I don't think it's ever had the anti corrosion stuff run thru it because some rusty water ran out in the beginning with the hose off.

 

Anyone know if it's normal for the pump to have a little knocking sound in there?

I would see about getting information on the pump and if there is a disassembly and cleaning you can do plus lubrication.

Yes I have watched several U tube vids on troubleshooting and easy fix its. Amazing the best ones are from a guy in Idaho called 'the Idaho Painter. He's got the best clearest vids.

you can take the intake tube off and clean it, or just get a few gallons of lacquer thinner then set it to prim. let it run for about an hour.

the packing kit to rebuild it is about 30$ and it's really easy to do.

make sure you put some throat sleeve oil where you see the piston rod going up n down.

when you store it not in use for more then a week or so, keep paint thinner in it with pressure on, no rust and it's when you leave the pressure off the the paint dries out in the packing cause air can reach it.

the 395's are great little rigs.

the knocking sound is the ball and seat at the bottom. when it won't prim that little ball is what has some debris not letting it seat.

do the lacquer thinner for a good while then do again with clean thinner. i have 5 airless sprayers and i do this method to all of them every fall. and i store mine with lacquer thinner in them all winter long. the ones i use regulatory get normal paint thinner for the cold nights. any more question let me know, i am a professional painter by the way.

i can walk you through or make videos on taking the pump apart if you need.

Thank you HR. I'm havin fun taking it apart and learning the workings. As soon as I put the Graco lube to the pump it ran much better. Opened the gear case cover and added more grease to the gears. That seemed to help. Will rebuild the pump like you say, you have me convinced, so going for a new seal kit today. So far I'm impressed with it's design build quality.

So just soak the intake and priming hoses in Lacquere thinner and then run it for an hour. Do you remove the filter screens?

I forgot how much fun it is to get a new toy that's old( might be 20-25 yrs old), pay so little for it ($125) and get it to work like new again.

 

HR, I did watch a U tube vid on the pump. I think I can figure it out..... though.... I might need help at some point.

i wouldn't take the hoses off. when i pick up a used one, i run the lacquer thinner though it for about 45 min to an hour, then i put in fresh thinner and re run for another 30 min or so. the filters are cheepish, get the different mesh for latex, oil, lacquer. if you plan on runnig latex and or lacquer though it get two separate pressure hoses and guns. that way you never contaminate the lacquer with latex bits.

 

post some pics if you can so i can see what vintage you have. i have 3 395's but they are all the same era.

 

soem good tips to have on hand are 411, 515, 517.  the smallest being the 411. oil and lacquer tip. 515 for interior latex, 517 exterior tip.

the way the tips numbering works is say 411/ the first digit 4, take that number and double it. you'll have an 8" spray pattern, 11 is the orifice size. you want to keep the gun 8-10" away from the substrate for an even spay patters., and over lap your pattern by half.

if your getting heavy line at both ends of the pattern then you need more pressure or thinner material. or maybe a new tip.

make sure you keep the filter in the gun clean as well. no need for a new hose unless yours has a hole in it. or you want to add one. the longest i think the 395's can go are about 100 foot.

 

to be a little more clear. run the lacquer thinner through the machine for about an hour. both with the prime leaver in the down or prime position, and then in the flat or pressure position. with you pulling the trigger on the gun.

Okay, running laquere thinner thru now for about 10 mins. and a bunch of paint flakes are coming out.  Amazing. Number of flakes are diminishing rapidly and are staying away from the pick up tube in the bottom of the bucket luckily. I have the gun off the hose going in the bucket. Works great.

does the siphon tube have a rock guard on it? if not you need one.

Update: I ran that for an hour and a half and then ran crud cutter thru it. White paint dissolved into liquid came out. Sprayer was obviously neglected.

Everything works well now except the gun does not shut off all the way. Oh well.... keep working on it

does the siphon tube have a rock guard on it? if not you need one.

It does and I ordered a pump rebuild kit for it.

I think I paid too much considering the amount of time getting it right.

not sure the model of gun, but they have a needle and seat, you should be able to take the front of it off like where the tip screws onto. i think it's a 9/16 i may be wrong. some debris may be in there or it might be time for a rebuild kit for the gun as well.

\good practice is to soak the gun in lacquer thinner as a few hours/days as well then wire brush or high pressure wash it off when the paint is all gooie.

Thanks HR, I will rebuild the gun too because after doing what you say I found no debris so it needs a new kit as well. I thank you for this help.

See if I can get some pics up today. It's difficult for a guy that ops on somewhat of a computer handicap

you might not have to rebuild the gun, most times adjustment is all that is needed.