Leak at Power Steering Pump Reservoir Cap - Possible Overheat???

[Kaline]

I recently bought my first W-body: a 1990 Oldsmobile Cutlass Supreme SL with the 3.1L/auto and 110K miles on it. The car appears to have seen reasonable care for most of its life.

 

Tonight I found out the mysterious leak under the hood is power steering fluid, which seems to be spraying out from UNDER the power steering reservoir cap. At idle when you turn the wheel, fluid sprays out from under the cap. It's made a mess underhood (I just degreased everything) and seems to me that the pump is over pressure. I could hear pressure relief when I took the reservoir cap off. Any idea what is going on? I've never dealt with a steering issue before. I looked thru my GM manual, but it does not have a troubleshooting section (one good thing the Haynes and Chilton's manuals have). Any input is appreciated.

[cutlassdude96]

bad cap seal?

[GP1138]

Yeah, see about getting a new cap. Are you absolutely sure it's from the cap, though? The pulley seal likes to fail, causing the fluid to shoot out all over the belt, and it gets fluid EVERYWHERE.

[luzmina]

I have replaced two P/S pumps in the life of my Lumina with the same problem you described and the leak in both cases was coming from the pump bearing spraying oil when you turn the wheels, it took me around one hour to do the job, the pump is around $20 with life time warranty.

[Kaline]

Update on the issue: I realized that the reservoir stated spraying fluid after an hour of city-driving thru neighborhoods. Lots of 90-degree turns, lots of low speeds (25mph max): the type of driving that really gives the steering system a workout. I think the power steering fluid was very old and I overheated it, which caused it to boil in the reservoir and spray out the cap seal. I had this happen once with my '94 Impala SS after a couple laps at Waterford Hills. I have refilled it with fresh Prestone Power Steering fluid, wiped up the mess underhood and it has not leaked since. Once I start driving the car daily (it still needs shocks, tires and an alignment) I'll report on it again.

[Kaline]

UPDATE: The power steering has been working fine ever since last September, until night Friday when my fiancee and I were driving around looking at houses. It was probably about an hour of low-speed (under 20mph) driving through neighborhoods when the power steering started blowing fluid out the cap. I think the system overheated. I refilled it with fluid and it's been fine since. I'm going to keep an eye on it to see if anything was damaged. I've got a mess of PS fluid to hose down, too!

 

Have any of you overheaded your power steering before? Did GM release a power steering cooler for these cars?

[95oldsVan]

The main PS hose is leaking,and until you change that,youre gonna get alot of air inside the system...I had the same problem on my 91 Lumina and until I changed the hose,it would eventually spray the fluid out.I replaced the main pump hose and the problem stopped...I did replace the pump 4 times until it dawned on me they cant all be bad and had to be something else...

 

So Check the hoses going down the pump and around the back of the engine...my 97 GP is doing the same thing right now and I looked in the back and seen the hose soaked with fluid...it has the same set up as the lumina I had...so do a thorough job finding any other hose leaks before replacing the pump.Im gonna replace the hose first before the pump.Just wanted to point this out.

 

 

 

[Kaline]

When you say main power steering hose, do you mean the high pressure hose? I'll check this hose on my car. Thanks!

[Pabz]

bad cap seal?

[95oldsVan]

When you say main power steering hose, do you mean the high pressure hose? I'll check this hose on my car. Thanks!

 

Yeah the High pressure hose...make sure theyre not leaking either..from what I learned,excess air in the system can cause fluid to flow out.Do check the cap seal as stated too..

 

[rjtiminskygtp]

I remember before I had my licence, and I was driving with my brother because he had his licence and i had my learners, and I turned and started driving and all of a sudden through the vents inside and the hood louvers, smoke started pouring out so I pulled over and opened the hood, and all around the power steering cap was soaked, the hood insulation was soaked, and the motor was soaked. I wiped it off and drove back to our hometown and then took it to the garage to get checked, and they looked at everything, and there was absolutely no problem, and it has never happened since. There is evidence everywhere that it happened but there was no source. The mechanic thought it may've had too much air pressure inside and expanded to the point it burped and then it was fine.

[Justin]

Sounds like you're on the right track. I've got a '89 GP that gets a very severe workout power steering wise and it will blow fluid out of the cap after a while. There are actually 2 little pinholes in the top of the cap that allow pressure to release under severe conditions, so as long as you keep the level within the lines you should be fine.

[DiscoStudd]

Did GM release a power steering cooler for these cars?

The 92-99 H-Bodies had PS coolers. They were also a common source for leaks, due to where they were mounted (on the frame rail - they got quite beat up being in that location...)

[1990lumina]

The reseveriour on my Lumina a lways seems "damp" with fluid...though it neevr actually leaks. I degrease it all, and the next day it's wet again, but it never goes past leaking off the top of the reseviour....usually was happened is dust clings it to it and I just leave it like that..it's wierd though...

[Dark Ride]

I had this happen a while ago on my car, It happened a lot for me, and eventually drained the reservior and I burned up the pump. Put in a new pump, never happened again. Try Flushing Your Power Steering System, it may have more shit in it than you think.

 

Mitch