C4 stiff steering
Oil Producer
Joined: Apr 2014
Posts: 9,368
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i “flushed” my 87, 86 and 85 steering racks with acetone and atf mixture. I let it sit in the rack for 5 min. then flushed with 100% atf and called it hood. i use atf as power steering fluid.
the “flush” procedure can be exciting. i fill the reservoir, and disconnect the return line and direct it INSIDE a 2 litre pop bottle. i tape the hose in the bottle!! the fluid flow and pressure out of the power steering pump is much much higher than i expected.
it will drain the reservoir in a second or two. so i was starting the car and shutting it down immediately to displace all the fluid. i raise the front wheels during this procedure so that i can turn the wheel left and right several times to move fluid in the rack.
the “soak” with acetone atf mixture was an experiment that worked, i had a rack that was VERY STIFF on center and turning the wheel required tonnes of force and then it would let go and jerk the car. im not sure why it worked or what the atf/acetone did, it was a shaken mix (put 50/50 into 2litre pop bottle and shook it up). that rack was fixed afterwards and i tracked the car several times afterwards prior to selling it. your results may very. use plain atf if you want to simple displace dirty fluids. you need to turn rack from lock to lock to be thorough. good luck.
the “flush” procedure can be exciting. i fill the reservoir, and disconnect the return line and direct it INSIDE a 2 litre pop bottle. i tape the hose in the bottle!! the fluid flow and pressure out of the power steering pump is much much higher than i expected.
it will drain the reservoir in a second or two. so i was starting the car and shutting it down immediately to displace all the fluid. i raise the front wheels during this procedure so that i can turn the wheel left and right several times to move fluid in the rack.
the “soak” with acetone atf mixture was an experiment that worked, i had a rack that was VERY STIFF on center and turning the wheel required tonnes of force and then it would let go and jerk the car. im not sure why it worked or what the atf/acetone did, it was a shaken mix (put 50/50 into 2litre pop bottle and shook it up). that rack was fixed afterwards and i tracked the car several times afterwards prior to selling it. your results may very. use plain atf if you want to simple displace dirty fluids. you need to turn rack from lock to lock to be thorough. good luck.
Last edited by VikingTrad3r; Sep 18, 2021 at 08:57 PM.
