Help with injector

[slash007]

I have a soap injector on my Tandem that will have suction for a few seconds once turned on, but then the suction stops. I replaced the injector and rebuilt the solenoid, but can't see anything else that I would suspect as causing the issue? Maybe it went out and got married? I can't find anything else to change and would appreciate any suggestions. Thanks.

 

[ShinePro]

LMAO


Do you have a foot valve?
Take it off see what happens

 

[slash007]

We actually tried just using the chemical and a short 2' line as a test and it only drew the chemical about 1'. This is for the Tandem, so chemicals are 90' away. Either way, suction stops, so regardless of how long the line is, it refused to draw more than 2-3 seconds.

 

[Greg Pack]

Not familiar with the tandem and even what brand injector, but the system has to have flow matched to the injector size to get proper draw. Too much air can retard flow and make the injector quit drawing. Try turning the air down if it is a foaming application. Also multiple clogged nozzle can reduce liquid flow. I had a wax that clogged a line and the injector quit drawing.

 

[slash007]

Not familiar with the tandem and even what brand injector, but the system has to have flow matched to the injector size to get proper draw. Too much air can retard flow and make the injector quit drawing. Try turning the air down if it is a foaming application. Also multiple clogged nozzle can reduce liquid flow. I had a wax that clogged a line and the injector quit drawing.

That's a great suggestion. Will check that out. Thank you.

 

[STXCW]

Which cycle?

 

[ShinePro]

Not familiar with the tandem and even what brand injector, but the system has to have flow matched to the injector size to get proper draw. Too much air can retard flow and make the injector quit drawing. Try turning the air down if it is a foaming application. Also multiple clogged nozzle can reduce liquid flow. I had a wax that clogged a line and the injector quit drawing.

Thanks Greg for jogging my memory
Getting old.
I had same problem with a foam and flo once
Put bigger injectors on to get more flow but they would not draw
Once I got the air removed they worked just fine.
Good suggestion!

 

[slash007]

Which cycle?

It's for the presoak on back bridge. I tried lowering the air today and it started putting out soap. The soap looked weak, so I tried adding air and it went back to water only. I then spent 30 minutes adding and removing air and never got it work again. I'll try again later and see if I can find anything else wrong.

 

[STXCW]

Have you checked the high pressure check valves on your manifold? You have 2 checks valves, one for each pump that leads from the outlet of the pump to the manifold. If one of them is bad, pressure will bleed off to the other side and you lose water volume therefore reducing suction at the injector.

 

[ShinePro]

What kind of injector?
And color?

 

[slash007]

Have you checked the high pressure check valves on your manifold? You have 2 checks valves, one for each pump that leads from the outlet of the pump to the manifold. If one of them is bad, pressure will bleed off to the other side and you lose water volume therefore reducing suction at the injector.

Not yet, but one thing I noticed today was that the right side was stronger than the left. The left seemed weaker and to be spitting more. I suspected a check valve and was going to check that theory next. With the Tandem you are working in the bay, so you have to move the machine and open the stupid cover then go to work. Will try it soon. That does make sense though.

 

[Greg Pack]

I will say that I built a vacuum gauge to help diagnose injector problems and it is a valuable tool when working on chemical issues. Cost like $20 from Kleen Rite to build. Just need a vacuum gauge, a 1/4 coupling, a 1/4" barb and a short section of hose. It will tell you quickly whether the injector is drawing the proper amount.

This may help:https://hydraflexinc.com/faq-troubleshooting/my-injector-wont-draw-chemical/

 

[Monte]

90% of the time...with this issue, I have found restriction down the line somewhere. Usually, Check valve guts dancing around causing variable restriction that is hard to see without stopping the air. With air off, it usually always becomes obvious, and the hunt begins for the restriction.

 

[Tech69]

Try switching the cables from a different solenoid and see if when you turn on that fluid it sucks if it does either have a bad relay pack or cables could be bad