PDQ G5-S HP Problem, Cat 2530 pump

[dannysaturday]

I have a cat 2530 on a PDQ G5-S, Wash was operating normally, all the sudden HP was pulsing and about half psi. Figured valves, took them out and found a little metal ring inside one of the valves, put it back together and pulsing stopped but the pressure was still only about 600psi. Ordered a new seal kit, put that in and gained about 50-100psi but still not right. The pump was making a squealing noise at start up for a second, but that cleared up. Here's what I do know:
Pump is getting plenty of water
New seals in the head
fairly new turbo nozzles

I did notice the pressure relief valve, where the divert-er for Gatlin guns or Arch is in the pump station is leaking slightly when HP is on. Not enough for a 300PSI drop, I'd think but could be wrong. Also my PSI on my LP soap manifold is around 200, and I've been having a problem of the some stream starting to weaken after presoak is about 3/4 way finished. PDQ said that should be higher but I don't think so.
I'm stumped, could it be the valves stems for the HP chemical manifold leaking back, back feeding into the inlet when not it use causing a problem? They're $170 each so didn't want to buy a few for no reason if that is unlikely.

Any ideas or help is greatly appreciated. Feel free to call or Text anytime.
Danny Saturday
904-753-6141

 

[Sparkleclean]

Danny did you fix this? If not call me tomorrow and i might be able to help you. Do you have the aluminum changeover valve that is air operated, or do you have the stainless steel one with the electronic danfoss valves on them? Im talking about the changeover valve the pressure relief valve is screwed i to. Also word of advice, i would keep a couple of the chemical valves on hand in case something goes wrong. If they are the newer model with the rounded edge on the electronic coil (held down by a phillips screw) they tend to suck. If they are the older version with the square coils (held down with a nut) they are more robust. There is also a service bulletin about the newer chem valves. You can not have your chemicals stored, or even run through hoses that rise over 15" above the water manifold height. The newer chem valves only hold back 1/2 psi which is equal to 15" according to the pdq engineers. The older square ones were stronger. That means your chemical tanks cant have liquid in them that exceeds the 15" level above the manifold in the pumpstation, nor can you run your chem lines out of the pumpstations and up to the ceiling and across a room to another pumpstation. nor can you have chemical tanks in an attic....etc, etc....

I would guess though that you might still have bad valves. You mentioned you fixed one and changed the seals, but did you change the valves or just fix it. If one fell apart i would guess they are shot and should be replaced. If the valves arent sealing properly you would gt chatter and a loss of pressure. Anytime i do any work inside the pumps i change the seals and valves at the same time. They are a pain in the but to work on while laying on the floor so i do everything at once to save the labor.

If none of this helped, and if you havent fixed the problem yet, call me, you have my number. Also feel free to call anytime you have a problem with your g5's, i like to talk shop and can probably help you with most issues.

 

[dannysaturday]

I have not found a solution yet! Since this post, I put a brand new cat pump in, and changed several of those chemicals valves with the newer style. Still getting 600 psi in the arch, when Gatlin guns are on they are putting out 1250psi. Would love to talk tomorrow if you're free, I'm not sure remember where I had your number. Thanks for the help!