my trooper has no brakes at all! :shock: i changed the master cyl. hoping that was the problem but to no avail. my next target is the booster. anyone know of what could go wrong inside of the brake booster? or how to replace it?
Usually the diaphram inside the booster goes bad. It cant be fixed, have to buy another booster. I havent heard of very many failing on any vehicle so a used one should be fine.
Also check the vacuum line going to it. I dont know if all isuzus have them but my manuals say there is a check valve in the line. If its bad it'll probably have the same effect. Alot cheaper then a booster.
To remove the booster remove the vacuum line, remove the master cylinder (again) then inside disconnect the push rod from the brake pedal and undo the 4 nuts to the booster. It should come right out then. Install should be the reverse.
One thing I found out y'day when I went to flush the brake fluid in my rodeo. It says in the manual to pull the ABS fuse, will not let the fluid flow right otherwise. Also says the engine MUST be running while bleeding the brakes or the booster WILL be ruined. Dont know if thats only if using the pump and bleed method or if it also applies to the mighty vac method but I didnt take any chances.
I know yours is older and a trooper not a rodeo so I dont know how much of that applies.