2013 Chevy Express 3500, 6.0l.
Just replaced the PS pump (AC Delco Reman) and hydroboost (AC Delco new) as they were both leaking. Due to some confusion in the various instructions I found, I did not properly bleed the system when I put it all back together. I missed the part about going lock to lock with the wheel before cranking it. I cranked it (not running it) a few times then ran it and went lock to lock with the wheel once it was running. Everything works great, no mechanical feedback or trouble as far as steering or braking goes. The problem I’m having is noise from the pump on turning or braking. When I press the brake, it makes the same PS pump noise as when I turn, I’m assuming because the hydroboost using the PS pump.
So I went back to the beginning and jacked it up and did 20 lock to lock cycles with the engine off, checking the fluid the whole time. Then put a vacuum on it and did 5 minutes each of center, right lock, left lock, and center. I checked the fluid again, still full with no bubbles. I repeated this process 2 times.
Then I started it and did 20 cycles lock to lock and pressed the brake several times with it running. Fluid still full, no bubbles or aeration.
I then reapplied the vacuum with the engine still running and repeated 5 minutes each of center, right lock, left lock, and center. I checked the fluid again, still full with no bubbles.
I reapplied vacuum and cycled lock to lock 20 times and pressed the brake under vacuum the whole time. Once again, fluid level stayed the same and no bubbles or aeration. At no point in this process did I ever lose vacuum, indicating that I have no leaks or loose connections.
After doing all of this, the noise level from the pump is the same. Is it possible that there’s still air in there after that much bleeding? Does a hydroboost system normally make more noise than a vacuum booster system? I’m thinking now that I got a bad pump. I don’t care about the noise, I care about the trouble that pump noise usually indicates. I’ve read good things about Lucas - is it worth putting it in the system instead of going through the install process again?
Just replaced the PS pump (AC Delco Reman) and hydroboost (AC Delco new) as they were both leaking. Due to some confusion in the various instructions I found, I did not properly bleed the system when I put it all back together. I missed the part about going lock to lock with the wheel before cranking it. I cranked it (not running it) a few times then ran it and went lock to lock with the wheel once it was running. Everything works great, no mechanical feedback or trouble as far as steering or braking goes. The problem I’m having is noise from the pump on turning or braking. When I press the brake, it makes the same PS pump noise as when I turn, I’m assuming because the hydroboost using the PS pump.
So I went back to the beginning and jacked it up and did 20 lock to lock cycles with the engine off, checking the fluid the whole time. Then put a vacuum on it and did 5 minutes each of center, right lock, left lock, and center. I checked the fluid again, still full with no bubbles. I repeated this process 2 times.
Then I started it and did 20 cycles lock to lock and pressed the brake several times with it running. Fluid still full, no bubbles or aeration.
I then reapplied the vacuum with the engine still running and repeated 5 minutes each of center, right lock, left lock, and center. I checked the fluid again, still full with no bubbles.
I reapplied vacuum and cycled lock to lock 20 times and pressed the brake under vacuum the whole time. Once again, fluid level stayed the same and no bubbles or aeration. At no point in this process did I ever lose vacuum, indicating that I have no leaks or loose connections.
After doing all of this, the noise level from the pump is the same. Is it possible that there’s still air in there after that much bleeding? Does a hydroboost system normally make more noise than a vacuum booster system? I’m thinking now that I got a bad pump. I don’t care about the noise, I care about the trouble that pump noise usually indicates. I’ve read good things about Lucas - is it worth putting it in the system instead of going through the install process again?