Hi,
My old 1986 560sl car didn’t turned realy from few years.
I have to verify a lot of things.
First i filled it with 98 gasoline, but now my motor turns at 1800 rpm mini!

Where is it coming from ? Automatic choke? Fresher temp?
How to slow it ?

I made 2 miles and the water thank was full !
Do you think it comes from motor speed ? Or old radiator?
Tk