How to Find Air Bag Leak on a Trailair Replacement Pin Box on a 5th Wheel Trailer

Question:

I saw you video about the air pressure in the Trailair King pin. I have two additional questions. First I fill my Trailair 18K to 90psi that works for me but I half to always fill it back up. Do I have a leak or could the pressure be two high and is being forced out? If I have a leak can that be repaired or do I have to replace the Air Spring?

asked by: Carl B

Expert Reply:

The 90 psi is within the capacity of the air bags used in Trailair pin boxes so it isn't that the pressure is too high. It does sound like there is a leak. The leak is likely at the inflation valve. You can put soapy water around and on the valve and see if it starts to bubble. That would indicate a leak. Or, even better, you could use Detect-A-Leak, # V02126, which is a lot easier than soapy water.

If it is leaking at the valve you can replace the valve. The replacement valve is # LC156740.

expert reply by: Michael H