Power Steering Leak - High Pressure Hose

[91LS400vgb]

I've had a persistent small p/s leak since I purchased my 91 LS400 less than a year ago. The power steering pump, rack and high pressure hose were replaced right before I purchased the car. Originally, I thought I was losing fluid through the idle up valve so I replaced that. However, the leak continued and I now have discovered that a small amount of fluid is leaking from the high pressure hose underneath on the driver's side that is threaded into a steel line (see picture). It is seeping out from the threads. I have tried tightening the connection but it won't budge, so I'm not sure what to do. Should I loosen it and apply some kind of thread sealant? The other thought I had was adding a power steering leak additive as the leak is very small - but I'm concerned that may not be the best option in the long run. Any advice is appreciated. Thanks.

[cardona6569]

Hello:

I had a similar problem. First if your fluid is not clean flush the fluid, remembering it uses Tranny fluid not PS fluid, (Clean is red like wine color with no dirt) I advise to clean the solenoid filter in the Rack. Second take out the High Pressure hose it has a crush gasket and a fitting that mounts in the PS Pump, (fitting looks like a steam from a faucet). Take the fitting which will come off the hose, and it does not matter where the holes go when putting it back in, touch the oblique the (tip) area after the threads, if they are burred, need to take sand paper (fine grade) and some Tranny fluid and make it smooth again, like you do in the faucets in the house. After that put everthing back togheter clean everything and use the Barrs no leak for transmission fluid and that should be the end of it. It was for mine and it has more than a year. Remember it will be difficult to take the fitting out. If it leaked for a long time, some fluid could be trapped in the bilges, need to give it some time but should not have much fluid coming out. The PS Pump does not have o ring that go with this part they are further down inside the pump and will not be affected by this. This saved me 600 pluis labor. You could also use the leak treament first and see what happens, but I doubt it will help much without the repair.

Good Luck!

I've had a persistent small p/s leak since I purchased my 91 LS400 less than a year ago. The power steering pump, rack and high pressure hose were replaced right before I purchased the car. Originally, I thought I was losing fluid through the idle up valve so I replaced that. However, the leak continued and I now have discovered that a small amount of fluid is leaking from the high pressure hose on the driver's side that is threaded into a steel line (see picture). It is seeping out from the threads. I have tried tightening the connection but it won't budge, so I'm not sure what to do. Should I loosen it and apply some kind of thread sealant? The other thought I had was adding a power steering leak additive as the leak is very small - but I'm concerned that may not be the best option in the long run. Any advice is appreciated. Thanks.

[91LS400vgb]

I just want to clarify that the leak is not at the end that attaches to the ps pump. It's beneath the car closer to the gear housing (see arrow in picture). I assume you mean I should disconnect the hose here and make sure the tip is smooth, otherwise smoothen it, then retighten and add the bar's leak for p/s. Thanks for your advice, cardona.

[91LS400vgb]

Just an update. A good mechanic I know indicated sometimes one can get away with just applying teflon tape on the threads. I've tried loosening the flare nut where the fluid is coming out but I am unable to do so as it is extremely tight. I even broke my wrench trying to loosen it. I may wind up just bringing it to the mechanic and letting him try with the risk that he will come back and tell me he has to replace the whole hose. My other option is just getting a new hose and installing it myself.

It seems all the power steering sealers out there work by swelling the seals and o-rings. That obviously wouldn't work here. Is there a product out there specifically for my condition where the leak is at the flare fitting?

[91LS400vgb]

Well, I can't get that flare fitting to loosen up, so I am considering replacing the whole high pressure hose assembly. I see there are banjo bolts at both ends. Anyone have any caveats before I go ahead and do this? I could not find a tutorial on replacing the high pressure hose and would appreciate any advice.

Btw, while I was under the car, I removed the solenoid filter using the hammer and screwdriver technique and found that the screens were 50% clogged. Also found a hole in one of the screens (perhaps intentionally) and a small tear in another.

[93ls400walt]

There are washers/gaskets at the hose bolts that can/need to be replaced. Thsy can be the source of the leak. Also some have said by cleaning the screen thay have lowered the hose pressure. And the leaking has stopped.

[91LS400vgb]

Thanks for your advice, cardona and walt. I refused to give up and finally was able to loosen the flare fitting. I had to rig up a 17mm crow foot to a 3/8 extension and a breaker bar, plus I held against using channel lock pliers. It was tough. I followed cardona's suggestion and used a fine emery cloth to smooth the sealing surface of the flared tubing. I sprayed some brake cleaner to remove any particles, making sure the rubber hose was covered to prevent contamination. I then wrapped the threads several times with teflon tape and tightened it using a 17mm flare wrench, using an adjustable wrench to hold against. Also, I made sure not to get any teflon tape on the tip. So far no leaks - I will monitor it over the next several days.

[93ls400walt]

Thanks for the follow-up