Hydraboost noise/oil foaming

[Chuck Leeper]

Did a search and an OLD thread I started is now back!
This time it's on a 71 Bronco. A DIY deal by someone yrs ago, using a HB without the safety accumulator.
This involves a brake failure via the rear hose being torn off. Luckily, the prop valve allowed for some ft brake.
The system was allowed to get dirty/rusty and required a new m/c and prop valve.
All's back together and the problem is:
Engine started, HB is charged and brakes "kinda work". Need bleeding.
With engine off, as we attempt to bleed, the p/s fluid in the HB bleeds back into the p/s reservoir and there's no pressure transmitted to the m/c.
My contention is the HB is fried and leaking internally.
Anyone help with ideas will be appreciated!

 

[1KWIKSIX]

PSC power steering reservoir should get rid of the foaming / aeration.
I’ve also installed a power steering cooler in order to keep fluid temps st bay & additonally running a full synthetic PS fluid which helps fight high temps & aeration

 

[jlat]

hello people: I don't think the res. is an issue. I looped one of the lines to hold more fluid and I think it works. My installation was a pain and it did not go smoothly. I did add a cooler and it whines a bit but it seems better than last year. I do plan on changing the fluid more than I should but I had a 94 Astro van for years and didn't do much with the fluid. I didn't even know what a Hydor boost was and it was in that van. Too bad as I donated the van with almost 300K on it as I would have removed it. I liked that van.
IBBY

 

[Chuck Leeper]

This is a new issue.
I've done more digging and have pretty much figured that the internal accumulator check valve has taken a dump, allowing the fluid to leak back to the p/s res. That's why we can't create pedal pressure.

 

[conn84gn]

After replacing everything else and still had noise and soft Padel noticed the gear box was leaking
Replaced that and the noise is gone and got a good pedal.