GMC Brakes

[rogerw24]

Good Day to you all

The Brake pedel on my GMC went solid with no movement at all. with the engine running and very heavy pressing of the brake the engine note changed but still no pedal.
After contacting the forum recently I was told that it was the Hydrovac that was the problem.

Went yesterday to remove the hydrovac, and before doing anything tried the brakes and they work again. Now this has happened before where they started working then without any notice the pedal geas solid and there is no brakes.
The brakes are not draging so I am at a loss where to go and hope someone can assist me.

Thanks in advance for any help.

Roger Walker

[John V Cliche]

Yup, Roger
I'm thinking a dirty/sticky,gummy Hyrdo-vac is the culprit also.
Hope his helps
John