Recently I was using a pressure washer to clean a concrete surface
prior to some masonry work. In doing so I unintentionaly blasted over
some rusty rebar and it stripped the rust off. THat got me thinking -
I have an old automobile rear axle that I need to clean up and instead
of using a wire brush in a grinder, that I might want to use the
pressure washer. I am not concerned with have the surface be a
spotless metal (nor am I concerned about the immediate rusting that
will take place as the water dries) - only to remove the scale prior to
applying a phosphoric acid treatment and then paint. I plan on opening
up the diff cover after pressure washer (once the axle asm is dry) to
check that no water got inside (other than the vent port or bad seals
there should be no entry of water). Off in Google land awaiting your
thoughts. TIA.

wrote:

Recently I was using a pressure washer to clean a concrete surface
prior to some masonry work. In doing so I unintentionaly blasted over
some rusty rebar and it stripped the rust off. THat got me thinking -
I have an old automobile rear axle that I need to clean up and instead
of using a wire brush in a grinder, that I might want to use the
pressure washer. I am not concerned with have the surface be a
spotless metal (nor am I concerned about the immediate rusting that
will take place as the water dries) - only to remove the scale prior to
applying a phosphoric acid treatment and then paint. I plan on opening
up the diff cover after pressure washer (once the axle asm is dry) to
check that no water got inside (other than the vent port or bad seals
there should be no entry of water). Off in Google land awaiting your
thoughts. TIA.

It won't get all the rust, but it will take off a lot. I have used a pressure
washer to knock a lot of the heavy rust off of a truck bed/frame prior to
working on it. Seemed to help a lot. I don't see how it can hurt, but I'm not
sure it will take off as much as you'd like.

GWE