Troubleshooting Air Compressor Leaking After Switch Replacement

Question:

Ive replaced the combination switch and valve for the control panel in the cab and the push on ribbed connectors on the back of the combo valve/ switch have a slow leak. The original valve/switch never leaked. I could put sixty pounds in the air springs and they would stay like that for ten years. I bought a whole roll of the red 1/4 OD plastic Airline tubing, so I have plenty to work with. Also have a hair dryer to warm it up if necessary. Would like it to be like it was. Must be a trick to getting those ribbed 5/32 little male connectors on the back of the valve to seal. Please advise.

asked by: John H

Expert Reply:

I'm assuming you're talking about the brass tee on the back in the picture below with one end open and the other two running into the switch and gauge. Did you use soapy water to identify the exact location of the leak? I only say that since there are a lot of connections going on here. Also, make sure you're using a hose cutter like # AL10530 when replacing any sections to keep your cuts perfectly square or you could end up with leaks in other locations as well.

Since you got the # F49ZR a week ago I will also assume you already tried installing a new section of hose and it isn't the old hose still on there that is leaking. This is just a barbed style fitting so I would say throw a hose clamp on it to keep it from coming loose/leaking. Heating the hose can certainly help you get it on but there are no special tips or tricks to get it to seal since it is designed to stay sealed from compression.

It could even be that some vibrations over time wore it down ever so slightly to a point that after removing the old hose it just isn't sealing like it did before. Since this is on a 2002 and you're replacing other parts I'm assuming you've had it for a while. You could potentially replace that fitting but it is not something we carry at this time. If you decide you want to go that route please let me know and I will see if Firestone has it available. I would still try a small hose clamp first, that will likely take care of it.

expert reply by: Robin H