My SLS has a leak somewhere and is getting air in the lines. I noticed last weekend that the rear of the car had dropped. I climbed underneath and manually pushed the control valve lever up, nothing happened. So I bled the lines and a lot of air came out. I again manually pushed up on the lever and the rear end raised up and stayed there. I looked at fluid resevoir under the hood and noticed there was about an inch left in the reservoir. I had filled it to the "max" line a week earlier. So I filled it to the max line again. Today I noticed that the rear had dropped. I tryed pushing the lever up and nothing happened. The reservoir again has about an inch of fluid in it. I can not find the leak, the control valve is sqeaky clean and the reservoir is dry on the outside and underneath. What could be leaking and where is the air coming from?

Thanks,
Gary
'81 300TD

Hi.

Only other things I could think of are
1. the rear shocks-they should be dry
2. those air cell things (resivoir balls)---common culprit, fairly easy fix
3. your sls pump, right on the front of your engine

Hope that helps, and I think once you find your leak, then you've found where the air is coming from.

__________________
1984 300TD Wagon--Astral Silver--Retired
1983 300TD Wagon--Dark Blue--Retired

The system is self-purging. An internal pump leak is the ONLY place that air could get introduced into the system. The leak inside the SLS pump is allowing the 'missing' hydraulic fluid to co-mingle with your lube oil. Bad scene.

All the components of the SLS, with exception of the supply line that runs from reservoir to the pump, are under positive pressure and consequently, cannot suck any air into the system. The output pipe from the pump, the lines to the struts and the accumulators are all under SIGNIFICANT pressure and any compromise of those items would generate a leak that you would have no trouble spotting.

The return line from the postion valve is under slight pressure and would show a leak as well.

__________________
Never a dull moment at Berry Hill Farm.

Fill the tank back up. Run the car so it lefts the rear up. Leave the car idling, and check for leaks.

Check below the the tank, especially the supply line that goes to the pump and check all the conections.

With the SLS under preasure you should see the leak more easily. Make sure you check the shocks...Most common place for the leak...

Just took a break here at work and went out to the car and looked under the hood. I didn't see any signs of leakage around the pump, lines or the reservoir. There seemed to be a small puddle of oil under the left rear spring area. I'll crawl under it tonight and check the accumulator and the shock. What really sucks is, I've poured three $15 bottles of fluid in the past three weeks.

Gary

Turns out one accumulator is leaking. The shocks are dry and not leaking.

Thanks for the replys.

Gary

Check the hoses to the accumulator as they are far more likely to leak than the accumulator itself. Also, be careful with the fittings as they are pretty soft and easy to strip. Where possible use a flare wrench.

__________________
LRG
1987 300D Turbo 175K
2006 Toyota Prius, efficent but no soul
1985 300 TDT(130K miles of trouble free motoring)now sold

I have a 78 6.9. There is a lot of information available for suspension issues on the various m-100 sites such as m-100.cc . If your rear level valve is old, the plastic bushings on the lever are probably brittle and cracked and if cracked badly enough, they will fall out of the contol lever. These bushings are big enough to greatly affect the ride height when they fall out. What I am getting at is that you really should be sure and use jack stands and other safety devices when crawling underneath a car with SLS and fooling around with the control valve.
My bushings failed and the rear dropped low enough to drag the muffler while I was driving the car.