Weird issue with brake pedal feel and PS pump

[KATOOM]

Today I happen to notice this larger puddle of oil under the truck.  Looking underneath it was coming from the PS pump and dripping at a rate of a drop every 30 seconds or so.  But why...?  The engine had been off for a day and no one was ever in the truck at any time doing anything like trying to turn the steering wheel or touching the brakes.  Thinking a hose let go, I eventually came to the conclusion that for whatever reason the PS fluid level raised up high enough to spill out the top and make a mess...with the engine off no less.   Yes, the fluid level was very high.

 

Then an hour later when I was parking the 5th wheel back in its spot I felt this weird bump in the brake pedal when pushing on the brakes quickly.  Not every time but every couple times I pressed the pedal it would that weird feedback bump and the other times would be smooth pedal action.  The only way I can describe how it felt was if the pedal was slightly hanging up on something giving this slight initial bump in the pedals movement.

 

Could both of these be related?  The strange phenomenon of PS fluid deciding to climb up and out of the reservoir while the trucks sitting parked, and a brake pedal hiccup.

 

And just to clarify, the brakes work great and the steering feels fine with no noise...

[Dieselfuture]

I'm pretty sure the problem is related, somehow air got in system. Maybe after your trip something got hot enough to do that. I'd blame it on your turbo blanket  didn't you say you smelled something like oil at one point when climbing steep grade,  could have been something to do with it. Sorry not trying to miss guide you or anything, just some random thoughts.

[01cummins4ever]

I had an issue like this a while back, Does the oil in pump reservoir look unusually dark ? 

[Mopar1973Man]

Just for heads up. Power Steering fluid should be changed every 30k miles. This doesn't mean suck out the fluid in the power and fill again. This means pushing over 2-3 quarts through the system until the output of the steering gearbox return hose looks clean. The steering box holds nearly a full quart by itself. 

 

3 Forgot fluids...

 

Power Steering fluid - Every 30k miles or every 36 months

Coolant - When the pH level drifts away from 7 and turns corrosive.

Brake fluid - Every 30k miles or every 36 months (Brake fluid is hygroscopic it will absorb water!)

[dripley]

9 hours ago, KATOOM said:

Today I happen to notice this larger puddle of oil under the truck.  Looking underneath it was coming from the PS pump and dripping at a rate of a drop every 30 seconds or so.  But why...?  The engine had been off for a day and no one was ever in the truck at any time doing anything like trying to turn the steering wheel or touching the brakes.  Thinking a hose let go, I eventually came to the conclusion that for whatever reason the PS fluid level raised up high enough to spill out the top and make a mess...with the engine off no less.   Yes, the fluid level was very high.

 

Then an hour later when I was parking the 5th wheel back in its spot I felt this weird bump in the brake pedal when pushing on the brakes quickly.  Not every time but every couple times I pressed the pedal it would that weird feedback bump and the other times would be smooth pedal action.  The only way I can describe how it felt was if the pedal was slightly hanging up on something giving this slight initial bump in the pedals movement.

 

Could both of these be related?  The strange phenomenon of PS fluid deciding to climb up and out of the reservoir while the trucks sitting parked, and a brake pedal hiccup.

 

And just to clarify, the brakes work great and the steering feels fine with no noise...

I just resealed my hydro boost and was having very similar issues. Pedal feedback, a weird noise every so often. I did get a grown out of the PS pump once but that was because the fluid level got very low. Everything worked fine. Mine was leaking from the hydro boost and not the PS pump though. I speculate that either of them leaking might cause the same symptoms if it let air into the system???

[01cummins4ever]

10 hours ago, KATOOM said:

 

 

Could both of these be related?  The strange phenomenon of PS fluid deciding to climb up and out of the reservoir while the trucks sitting parked, and a brake pedal hiccup.

 

 

air in system could cause fluid to rise, but in my situation it was engine oil being introduced into pump reservoir from a bad vacuum pump seal and a bad power steering pump seal. I chased this problem to no end, their was no sign of leakage from the vacuum pump, but came to the conclusion that the power steering pump was being contaminated and the level filling up with engine oil. When I pulled the vac pump and steering pump off, the vac pump seal was butchered, so I just assumed it was drawing in engine oil from the bad seals. I resealed the vac pump and put on a reman power steering pump and problem went away.

Edited August 8, 2018 by 01cummins4ever

[dripley]

I had to go back and re read. Dont know how I did not pick up on the fluid level rising. But I did'nt.

[KATOOM]

5 hours ago, Dieselfuture said:

I'm pretty sure the problem is related, somehow air got in system. Maybe after your trip something got hot enough to do that. I'd blame it on your turbo blanket  didn't you say you smelled something like oil at one point when climbing steep grade,  could have been something to do with it. Sorry not trying to miss guide you or anything, just some random thoughts.

 

Yes, you're correct and after seeing the leak and all the oily crap under there, I remembered that I did smell oil on that climb.  I cant say whether or not the heat of the climb was related but maybe...

 

3 hours ago, 01cummins4ever said:

I had an issue like this a while back, Does the oil in pump reservoir look unusually dark ? 

 

No darker than normal PS fluid.  Reddish color...

 

3 hours ago, Mopar1973Man said:

Just for heads up. Power Steering fluid should be changed every 30k miles. This doesn't mean suck out the fluid in the power and fill again. This means pushing over 2-3 quarts through the system until the output of the steering gearbox return hose looks clean. The steering box holds nearly a full quart by itself. 

 

3 Forgot fluids...

 

Power Steering fluid - Every 30k miles or every 36 months

Coolant - When the pH level drifts away from 7 and turns corrosive.

Brake fluid - Every 30k miles or every 36 months (Brake fluid is hygroscopic it will absorb water!)

 

Agreed, but I've sucked the fluid out and replaced it twice in the past few years with only about 30k miles since then.  And it was with full synthetic PS fluid as well.  So I cant imagine its because of old cooked fluid.  There has to be another reason...

 

2 hours ago, dripley said:

I just resealed my hydro boost and was having very similar issues. Pedal feedback, a weird noise every so often. I did get a grown out of the PS pump once but that was because the fluid level got very low. Everything worked fine. Mine was leaking from the hydro boost and not the PS pump though. I speculate that either of them leaking might cause the same symptoms if it let air into the system???

 

This is interesting.  I guess I didnt think about the hydroboost system being static.  I'll look for leaks elsewhere indicating a drainback which could have allowed fluid stock to overfill the reserve.

 

1 hour ago, 01cummins4ever said:

air in system could cause fluid to rise, but in my situation it was engine oil being introduced into pump reservoir from a bad vacuum pump seal and a bad power steering pump seal. I chased this problem to no end, their was no sign of leakage from the vacuum pump, but came to the conclusion that the power steering pump was being contaminated and the level filling up with engine oil. When I pulled the vac pump and steering pump off, the vac pump seal was butchered, so I just assumed it was drawing in engine oil from the bad seals. I resealed the vac pump and put on a reman power steering pump and problem went away.

 

I'm puzzled by this...  I dont believe it would be possible for the PS pump and the vacuum pump to share fluids under any circumstances.  Matter of fact, there's a gap between the two so if either component seal was bad then a leak would simply drain between the two.  No?

[Mopar1973Man]

31 minutes ago, KATOOM said:

I'm puzzled by this...  I dont believe it would be possible for the PS pump and the vacuum pump to share fluids under any circumstances.  Matter of fact, there's a gap between the two so if either component seal was bad then a leak would simply drain between the two.  No?

 

You are correct. They can't share fuilds. 

[adamey1000]

sounds very much like a hydroboost issue. as others have said, if a seal let go and introduced air, that would explain the fluid rising. That is what mine did around a year ago. Flushed the PS pump and replaced the hydroboost, problem gone. I didn't even realize how much brake pressure I was having to use on the bad booster until I about threw myself through the windshield with the new booster. 

[01cummins4ever]

3 hours ago, KATOOM said:

 

 

 

I'm puzzled by this...  I dont believe it would be possible for the PS pump and the vacuum pump to share fluids under any circumstances.  Matter of fact, there's a gap between the two so if either component seal was bad then a leak would simply drain between the two.  No?

I was scratching my head over that too, but how else do you explain pumping out more fluid than the system holds over a month or so duration and fluid turning black.  here's an old thread I started a few years back.

 

maybe since your fluid is still reddish in color it may not imply, 

overflowing power steering fluid - 2nd Generation Dodge 24 Valve Powertrain - Mopar1973Man's Dodge Cummins Forum.url

[KATOOM]

OK, so I got home from work and did some checking.  I dont see any leaking from the hydroboost.  Its not clean and the bottom of it is sort of oily but its been like that forever.  Meaning, nothing new and excessive.

 

The pump is oily and again dripping.  So obviously there's a leak somewhere allowing the fluid upstream to flow back down into the pump.  Things are pretty oily and wet around the pump so its hard to distinguish where or what could be leaking in addition to whats spilling out the lid.

 

Then I checked pedal feel with the engine off.  When I pressed on the pedal the movement had some chatter, not smooth.  Even if I pumped the pedal a few times the chatter would remain.

Then I started the engine with my foot on the pedal and nothing happened.  The pedal did not push back against my foot and if I held my foot pressure against it, the pedal would drop to the floor and I could hear a slight hiss.  I didnt move the truck either, and just shut it down.

 

So all that said, I guess I'm looking at three options?

1) There's a leak in the system.  Likely a hose or something I cant see.

2) The PS pump outlet is plugged up and not providing the hydroboost with adequate fluid pressure.

3) The hydroboost is toast.

 

Any suggestions before I start throwing parts at it?

[adamey1000]

11 hours ago, KATOOM said:

I dont see any leaking from the hydroboost.  Its not clean and the bottom of it is sort of oily but its been like that forever.  Meaning, nothing new and excessive.

This doesn’t necessarily mean that the hydroboost is not the source of the leak. It is the high point in the system. So if a seal was broken, you wouldn’t expect to see much in the way of fluid leaking there. The only time it should leak would be under pressure. If the leak were below the level of the reservoir, you should see a low fluid level and the leak would be from whatever component had the hydraulic seal broken. 

 

11 hours ago, KATOOM said:

Then I started the engine with my foot on the pedal and nothing happened.  The pedal did not push back against my foot and if I held my foot pressure against it, the pedal would drop to the floor and I could hear a slight hiss.  I didnt move the truck either, and just shut it down.

 

A properly functioning booster should push back against your foot when you start the engine. But the fact that the brake pressure leaks down is curious. If the master cylinder was good and the booster was bad, it should still hold pressure. 

 

On one one of my father in laws cars, he was having a problem where the booster was actually applying the brakes itself. A dried out grommet was preventing the pedal from returning fully to the top, which allowed the vacuum pressure to suck the pedal back down. Unless you reached down and pulled the pedal up to the top of is travel, the brake pedal would slowly go to the floor on its own. Totally different meathod of operation, but the principle is the same. I just tell that story to say boosters do odd things sometimes. 

Edited August 9, 2018 by adamey1000
Edited for clarity

[Haggar]

K,

 

Here is a good article on the hydroboost.  http://www.brakeandfrontend.com/operation-diagnosis-and-repair-of-hydro-boost-power-assist-systems/

 

Here are the quick test procedures.  It sounds like your accumulator is bad for certain, and maybe another seal or two.

Edited August 9, 2018 by Haggar

[dripley]

I just resealed mine. It was all working fine but seal between the case halfs had sprung a leak. I went thru 2 quarts in about 1000 miles.  I used the article in the articles section here and some info @Haggar provided a while back on getting the brake rod off. Unfortunately due to the thunder storms I lacked the time to do this part. I hope that does not come back to haunt. Because I did have a small leak that showed up on the floor mat about 3 months back. So far nothing during the the trip to and from Maryland. All is working hotmstraight and normal.

 The job is not difficult. Getting to some of the bolts is not much fun especially under the dash. Just an awkward place to be. I did struggle a bit trying to get the case halfs back together. I either kept dropping either one of the springs or had a hard time lining up the spoolvalve and the power piston to get them back together. All an all not a difficult job just awkward. 

 

[Mopar1973Man]

As long as I keep changing my power steering fluid I hope that I don't have to do that job for a long time yet. 351k and rolling...

[015point9]

20 minutes ago, Mopar1973Man said:

As long as I keep changing my power steering fluid I hope that I don't have to do that job for a long time yet. 351k and rolling...

 

Any info on best way to change?  I dont think my Turkey baster is getting out very much.

[Mopar1973Man]

Basically, you want to unhook the steering box return line. Now cap the pump nipple to keep fluid in the reservoir. Now route the return line to a waste container. Now jack up the front axle. Now with the ENGINE OFF, KEY OFF position to unlock the steering wheel. Now slowly go from lock to lock. The steering gearbox will pump the fluid out. Keep the reservoir full and keep doing this till the fluid runs cleanly on the return line. Typically I use close to 1 gallon to flush and refill the system. 

 

The steering gearbox by itself holds close to a quart of fluid. Turkey baster will not work at all.

[KATOOM]

18 hours ago, Mopar1973Man said:

Basically, you want to unhook the steering box return line. Now cap the pump nipple to keep fluid in the reservoir. Now route the return line to a waste container. Now jack up the front axle. Now with the ENGINE OFF, KEY OFF position to unlock the steering wheel. Now slowly go from lock to lock. The steering gearbox will pump the fluid out. Keep the reservoir full and keep doing this till the fluid runs cleanly on the return line. Typically I use close to 1 gallon to flush and refill the system. 

 

The steering gearbox by itself holds close to a quart of fluid. Turkey baster will not work at all.

 

I thought I remember you talking about taking off the pressure line at the PS pump which runs up to the hydroboost and pulling out the screen filter?

Edited August 10, 2018 by KATOOM

[Mopar1973Man]

28 minutes ago, KATOOM said:

I thought I remember you talking about taking off the pressure line at the PS pump which runs up to the hydroboost and pulling out the screen filter?

1

 

Nope not I... I'm going to guess it would be @Cowboy .