Hydroboost Bleeding Issues

[6600DURAMAX]

Having a bear of a time getting this hydro boost to bleed and or function correctly -makes me wonder a few things ...... I have the vehicle on jack stands - no wheels . I have turn the steering wheel 20-30 times lock to lock and still have air. When I start the truck the pedal feels awful -wont return all the way, the steering feels crappy as well. Then when I shut it off the reservoir overflows everywhere .....

Do I have a hose routed incorrectly ?? What gives ......

Its a new hydroboost unit and new/rebuild PS gear box

[6600DURAMAX]

here is the ps box

[Richard]

Kind of hard to tell exactly where the hoses are going to in the pictures. In the second picture the hose routed over the hydroboost should go the PS pump. Having that large inverted trap in the main feed line is not going to make bleeding any easier. It also makes that trap the highest point in the system. Maybe try running motor, turn off then cycle steering.

[6600DURAMAX]

does this help

I have started it numerous times......... I just want to ensure nothing else is wrong

PLUS it shoots fluid out of the reservoir every time I shut the engine off as well

[57taskforce]

It’s Plumbed correctly.
Try filling the reservoir while it’s running, my setup did exactly what you are describing and the reservoir on my pump wasn’t big enough to supply the whole system from empty if that makes sense, and would start cavitating and aerate the fluid causing the volcanic eruption of foamy oil when you shut the engine off. Once I filled the reservoir with it running the cavitation stopped and it bled out really quickly.

[Richard]

The inverted trap in the pump to hydroboost is causing the drain back to pump and reservoir to be worse.

[6600DURAMAX]

Richard - what do you mean by inverted trap ?

[6600DURAMAX]

57 - I'll try that. Do you have your reservoir mounted higher than I do ? Mine is about 3'' below the top of the radiator for reference

[57taskforce]

I have the stock pump and reservoir off of a 72 v8 K20.

[Richard]

Originally Posted by 6600DURAMAX

Richard - what do you mean by inverted trap ?

A sink trap is a U shape. The hose from Hydroboost to pump forms an inverted U shape. The top of that is the highest point in your system. I would turn 90 at hydroboost and route hose under unit. Will help equalize pressures in the hoses going to the unit and should help with bleed back. Yes, getting reservoir higher will help as well. Even with the hydroboost unit or higher would be best if attainable.
Make sure the line from reservoir to pump has a good downhill angle is a necessity, it should not be level or form a trap.

[6600DURAMAX]

I'll have to reevaluate the entire setup if the reservoir needs to be higher - there is really not a good way with this style /setup. The feed line from the reservoir to the pump is definitely not at a downhill slope that's for sure.

I'll see if routing the hose under the unit is possible.

[6600DURAMAX]

I violate almost every one of these item of " what not to do" ..... Guess its back to the drawing board for reservoir placement .....

[Willie Makeit]

Originally Posted by 57taskforce

It’s Plumbed correctly.
Try filling the reservoir while it’s running, my setup did exactly what you are describing and the reservoir on my pump wasn’t big enough to supply the whole system from empty if that makes sense, and would start cavitating and aerate the fluid causing the volcanic eruption of foamy oil when you shut the engine off. Once I filled the reservoir with it running the cavitation stopped and it bled out really quickly.

I have experienced the same. Filled when running and issues went away.

[6600DURAMAX]

I have my reservoir outlet way below the pump ..... I'm sure this needs corrected ASAP. Headed out now to see how it can be mounted differently

[6600DURAMAX]

fabbed up a mount to mount it directly above the pump on the driver side head - now I need some new ferrules for teh PTFE hoses and I'll be ready to fire this up again - hopefully with better results

[Richard]

Would bet the farm this is the main problem. Good to hear you came up with a solution.

[6600DURAMAX]

Okay - mounted the hydro boost reservoir directly above the pump

Been working on bleeding it - seems to be getting better but quick question

1. the ps fluid in the reservoir continues to fluctuate up and down - is that normal?? It will almost overflow the reservoir then go down to 1/4 full when cranking the wheel from lock to lock

2. Fluid is not foaming and appears to not have much air in it

[57taskforce]

Yea the fluid level fluctuations are normal, because the fluid is being directed thru the system assist in braking and steering.

[6600DURAMAX]

Darn it ---- still have issues

When motor is off reservoir is about 1/3 full - when I crank the wheels back and forth fluid level rises to the very top of the reservoir - then when I crank the wheels back the other way the fluid drops to about 1/3 again..... all seems fine

HOWEVER - when I start the engine the reservoir empties thus allowing air back into the system.

When shut off the fluid level returns to about 1/3 then when cranking wheels with the engine off the fluid rises all the way back to the top ( essentially overflowing) ....

Is my reservoir to small ?? Something is a miss here

[6600DURAMAX]

Doing my calculations the reservoir is roughly 16 oz

Its a billet reservoir from CVF

[Getter-Done]

I can't answer the reservoir capacity question.
I was just wondering,
Did you go with a oil cooler on your system?

Hope you can find your issue with this.

Sounds like you are bleeding the system correctly.
Here is a link I have saved.

Link: https://my.cardone.com/techdocs/930394-52.pdf

[6600DURAMAX]

No cooler in the system - considered it but decide against it

[Richard]

Hate to say it but I still see a problem with the reservoir and hose to pump. There is a considerable trap in the hose. Both sides of the trap are fairly close in height preventing fluid to flow easily into pump. Maybe try clocking the PS pump so inlet fitting ievel if possible. If no, maybe changing the fitting into pump with a tight 90 would help by making the trap smaller. Some fittings I am speaking of https://www.lsxconcepts.com/collecti...-pump-fittings

[roboticjunky]

So I just went out to my garage to check the routing on my hydroboost (which the car came originally with). The single hose on the motor side/towards the passenger side is for high pressure from the ps pump. The hose closest to the firewall on the fender side is high pressure to the gear box and it goes to the thread hole closet to the frame. The hose closest to the master cylinder on the fender side is the low pressure that goes back to the reservoir. The threaded hole closest to your front driver side tire is the low pressure side and goes back to the reservoir.

Here are some pics to help explain.

[roboticjunky]

Here's another pic, but doesn't show the gearbox because it's for a rack and pinion. The black hoses in the pic are the high pressure ones.