What Would Cause Roadmaster Invisibrake to Stop Building Pressure

Updated 10/07/2020 | Published 10/06/2020

Question:

My invisibrake will not hold pressure. It is not maxed out either. I cant get the adjusting knob to do anything it shows no pressure at all. The unit runs but doesnt build pressure. How can I fix this.

asked by: Gary F

Expert Reply:

I spoke with my contact at Roadmaster about the InvisiBrake # RM-8700 issue you are having and he told me that the first place to check is the vacuum line that leads to the engine. If that is kinked it will prevent it from building any pressure.

He did say that if you sit for long enough the pressure will eventually bleed off.

expert reply by: Jameson C