Gq brakes

[rednut]

Having some trouble with the old GQ brakes
On first start up the pedal feels ok take of up the road and the pedal becomes hard the car still stops but need to put a bit more force into the pedal
Also with the engine sitting at idle push the pedal to the floor then release it the engine drops revs and become rough for a few seconds
I was thinking brake booster?

[BigRAWesty]

Vacume system.
Start at the source of the vacume, and work along the lines and check each join.
You'll find it.. Just takes time

[rednut]

Check the vacume system there is no real loss of vacume all the way to the booster

[BigRAWesty]

Any sorta loss on these old boats will be a big thing.
Have you got any other units using vacume??

[93patrol]

Get a hand vacuum pump on your brake booster see if it hold vacuum if not that's your issue otherwise its perished lines or if you have a diesel it's the vac pump on the alternator

[rednut]

4.2 petrol and the only other thing on that line is the clutch booster

[BigRAWesty]

Try garb a vacuum gauge and do 93's test. It is quite Possibly the booster..

[rednut]

Looks like the master cylinder was leaking at same time and was replaced by previous owner paint has peeled of the booster and the inner guard