Air-Assisted Air Pump Issues

When the air pump starts to misbehave, sometimes fiddling with the pressure can be an easy short-term fix. March 28, 2012

Question
I'm having issues with my Kremlin pump. What's happening is when the piston goes down when it hits its lowest point it will kind of hang for a second then resume normal function until the next down pump. I've replaced my mvx with a brand new excite so itís not a gun issue. I've checked all filters.

I'm spraying Bernel facet lv 90 lacquer same as I have for years. I took the pump apart and cleaned it as much as I know how to do. This fixed the issue or maybe five minutes and then it returned. I have tried doing a good flush with zeroresults.

Forum Responses
(Finishing Forum)
From the original questioner:
I just made an observation but canít remember if it's normal or not. I donít think it is. Whenever my pump pumps (piston reaches top or bottom) I lose about 4-5 psi of fluid pressure. This is causing the wink. Any known causes of this?



From contributor H:
The air motor needs repair it is either the springs that are bad or the little seal that is on top of the air motor rod - this can cause erratic shifting. Also, look to see if you can hear any air leaks from the top of the motor. One other thing you can do is to turn up the pump pressure a little.


From the original questioner:
Any idea where I can find directions for replacing the seals and springs? I have the parts but do not have the knowledge to replace.



From the original questioner:
I should also add I would have it repaired professionally but the local Kremlin dealer has a two week turnaround time, which is the reason I had to buy a new xcite instead of just fixing my mvx. I would love to buy a new pump but I really can't afford it at the time as they are expensive.


From the original questioner:
Contributor H - thanks for the advice on upping pump pressure. I never really thought about that as I've been running the same settings for years. I upped my fluid to 40-42 and my air to about 17-18 with the trigger pulled and it has pretty much eliminated my issue.

I've been toying with a #9 tip for the last week or so to get more product on per coat and to increase speed. My problem is my tip is regularly getting clogged and I cannot complete a full rail without having to stop and de-clog it. My number six can easily go two days without the fan being affected. I run a filter on my dipstick as well as where the gun meets the fluid hose.



From contributor G:
You are now running your air pressure higher than before - right? This may be causing the material to dry on the tip where you didn't have so much air before.


From contributor H:
To make the pump run faster you do not need to necessarily raise the atomized air unless you are getting tails. As far as clogging goes, I used to use thinner general purpose but I found if I used a higher quality thinner I didn't have as many problems, just a thought

How old is your hose? If you spray post-cat hoses just clog over time, same with the dip tube. The nine tip is larger than the six and you should have less clogging not more, unless you are using the black tip seal in the six which is a pretty tight mesh filter.