dennismorgan

Enough mechanical parts can go bad without helping the process.
While fixing a low voltage electric brake problem on my 30 foot fifth wheel,I put my steering lock bar from my seat to the brake petal so I could check trailer brake voltage while the motor was running.Well I probably left the petal depressed to long and power steering fluid started leaking out of a hole on the underside of the booster pump combo power brakes unit.
Can anyone confirm I did infact destroy a perfectly functioning expensive part?

patdaly

Ouch, you mean the Hydraboost unit that the master cylinder is bolted to?

If you have a leak out of that, and it isn't from the hose, that isn't good.

dennismorgan

Yes,thats the one,the power steering boost for the brakes,Looks like a small vent hole on the bottom side,perhaps it is there for when an internal seal blows out it alerts you by way of fluid dripping.My question is,can you create to much pressure in that unit by depresing the brake for long periods of time with motor running ,for the purpose of checking electric brakes on trailers.

DIESELWRKS

Mopar1973Man's Dodge Cummins Articles - Brake Hydrobooster Rebuild

dennismorgan

Thanks,that tells it all,I would defiinatly take a shot at fixing a leak in the hydra boost unit with that in depth info.
However,i,m to late recieving the info,I already hired a mechanic who changed it out for a remanufactured one from autozone.Cost me $266 dollars labour part included in Mexico.But I do love it whenever I can beat the system,repairing an expensive complicated part myself for cheap.
One thing your article did not cover,that little drain hole on the bottom side of the hydraboost unit,the mechaic told me the drain hole works both ways,if your master cylender was leaking internally it would drip out of that same hole,in my case it was the hydra boost leaking power steering boost.
There may aso be a lesson here to be learned as my son told me he has done the exact same thing checking his electric trailer brakes,putting a bar between brake petal and seat,the power steering pump puts out like 1900 psi and is unnatural to depress your brake petal for so long.
Thanks again,kind of kicking myself for not waiting a little longer for a response,but when my truck is down,all is not well in the universe!

SIXSLUG

Glad you got it fixed....the hydroboost unit can be a pain to repair, especially if dirt gets into the system.....