Fluid leak (PS pump or low pressure hose)?

jseabolt · December 9, 2017

So about a year ago, I started smelling something from the engine compartment while waiting at red lights and what resembled steam. I knew power steering fluid was going somewhere because there was fluid all over the frame below the pump. Initially I thought maybe the pump seal was getting worn so I put a few CCs of that White Shepherd stop leak in the fluid. OK I know what you guys are thinking. This stuff is snake oil but I've used this stuff many times and I've always had good luck with it. It's always stopped the leak and caused no ill effects. Well that didn't fix it.

Apparently the high pressure hose was leaking from around the fitting. I was going to replace both hoses but the guy at the auto part insisted that the low pressure hose never goes bad. Really? So I just replaced the high pressure hose at the time. This seemed to slow the leak down.

Before heading off to Washington D.C. in November for a car show (yeah in the middle of D.C.) I topped the reservoir off as well as a quart of motor oil every 2000 miles as usual. So when I get back (~800 mile round trip) the reservoir is half full so it's lost that much since. And there is fluid on the frame and both hoses. But just from looking at the pump, I cannot see any fluid around the pump itself.

I went back to the auto part store to inquire about a low pressure hose. I asked him to take a look to see if he could tell where the leak was coming from. He looks briefly at it (said it was too cold for him to be outside). He still insists that the low pressure hose cannot possibly leak because there is no pressure on it. He says it's the pump and it's "dripping" onto the frame and hose fittings. So it just looks like it's coming from one of the hoses.

Here is what baffles me. If the seal was bad on the pump, wouldn't it be slinging fluid all over the place? On to the belt causing it to squeal? Reason being is I work at a chemical plant and when a pump seal fails, it sprays out in all directions.

This guy has been helpful to me in the past so that is why I try to do business with him instead of the chain stores. He has ran the independent auto part store here in town for ages. Unlike those high school drop outs the chain stores hires that knows nothing about cars.

The alternator went out on this van and I decided to replace the idler and tensioner pulleys and serpentine belt while I was at it and one of the chain auto part stores kept giving me the wrong parts. He even put a new belt on it in outside the store for me to make sure this one was going to fit.

This time it seemed I was taking up his time trying to rush me out of his store. Something about having to put his parts order in before 10:30 or it would be delayed a day.

Anyway. I was thinking about replacing the low pressure hose (can't hurt) because it's much easier than replacing the pump to see if this stops the leak. One thing I have not checked is the hose from the reservoir. It could be leaking from this hose.

What do you guys think? If the pump seal was bad, wouldn't it be slinging power steering fluid, not dripping it?

SierraDually · December 9, 2017

If it were me, I would clean all around the area of the p/s pump and hoses, get all the grease and crud off of there. It will only take 5 minutes. You don't need to be able to eat off of there. Just get it clean then drive it for an hour or 15 minutes or whatever it takes and have a good look at the area. It should be plainly obvious where the fluid is coming from. Alternatively you could have someone else turn the steering wheel with the engine running and have someone else look at the suspect area while the steering wheel is being turned. If it is a really bad leak you may be able to see the fluid coming out when the system is under the pressure of a moving steering wheel as opposed to a stationary one.

If you replaced the high pressure line, it's easy to mess up an o-ring while threading it in or to try and re-use an old o-ring. Then you start leaking from where the hose fitting threads into the pump body because of a 5 cent o-ring. Did you use new o-rings when you replaced the hose?

jseabolt · December 9, 2017

The guy at the autopart store had me to turn the steering wheel in both directions and said he never saw any fluid coming from the low pressure hose.

You made a good point on something I forgot to ask. I don't remember the O-rings until I looked up this photo of a power hose but I'm assuming new hoses came with them. Usually anytime I replace a rubber seal (even brake caliper seals) I give them a good coating with Dow Corning's O-ring and valve lubricant before installing them.

SierraDually · December 10, 2017

In that case I would clean the pump or wherever it's leaking and then recheck before fluid gets everywhere again. It won't be too hard to pinpoint.

For example, if you clean the low pressure hose then you will see a wet spot afterwords where the fluid is coming from.

Just wipe it down to dry with a couple rags. Usually when things are dirty the leaking area is the cleanest area already, because the constant fluid flow tends to clean off any dust etc. If you can post a couple pics with good lighting that might help

sdeeter19555 · December 11, 2017

Could be the fluid getting hot or foaming and blowing past the cap? That cap is like a radiator cap, and has a pressure release.

Steve
2012 2500hd 6.0l

jseabolt · April 24, 2018

Been awhile since I made this post. So today I decided to replace the low pressure hose. I went to another autopart store.

Kind of hard to tell but here's what the leak looked like:

https://drive.google.com/open?id=1nr2fckW_zTnhivCc9HQNky0tWLg6Dc58

The hose wasn't cracked but could have been a worn O-ring.

I de-greased the area and will monitor any fluid leakage.

I did have one of those "DUHH" moments. I wonder if I over filled the reservoir and as the fluid got hot it expanded and was leaking from the cap. When I posted this, the reservoir was half full below the dipstick so there must have been a leak.

txab · April 24, 2018

A low pressure hose can leak usually at the ends. Sometimes when hose gets hard from age and heat. Couple that with a hose clamp the no longer tightens very well . So did you put the orings on the HP hose? Also did you make sure you removed the old o-rings?

jseabolt · April 25, 2018

Yeah. Before I left the auto parts store I made sure the new hose had an O-ring with it. The O-ring with the old hose was just like the other one where it was stuck on the fitting. I noticed it was concave shaped. I don't know if the other end was also concave and it just conformed to it's shape over 20 years.

One of the biggest issues was trying to compress the ends of that stupid clamp with a pair of pliers. I hate those type clamps and usually replace them use a worm type clamp and a 1/4 socket and ratchet.

While I was cleaning up my tools, I decided to clean the old hose up as well just to see if I could tell if there was anything wrong with it. I thought just for kicks I'd cover one end and shoot some compressed air in the other end and stick it in my parts washer to see if any bubbles may form around the hose.

jseabolt · April 25, 2018

I just checked the level in the reservoir. According to the dipstick the level when cold is with the reservoir about half full. When I last checked it, the level was half full, most likely where it needed to be to begin with!

There is a short window between the add mark and full when cold. Like 3 or 4 ounces. I siphoned some out of the reservoir down to the add when cold mark and will monitor.

I guess I did not take into account that power steering fluid expands as it get's hot. I knew automatic transmission fluid expands but didn't think about the power steering pump generating heat.

I'm thinking I may just overfilled the reservoir and it was blowing it out around the cap. Since there was fluid on the reservoir as well as the ECU, frame and steering box. Who knows it could have been leaking from the hose as well as the reservoir cap.

It probably wasn't a bad idea to change the hose anyway being the van is 20 years old. I replaced the high pressure hose a couple of years ago because it was blowing fluid all over the engine compartment.

Dad just about lost his 76 Chevy pickup one day. He installed an external transmission cooler and one of those hoses busted in 25 years later and the truck suffered an engine fire.