Hector 313

Hi I have 2012 c216 cl500 I rebuild the engine my self replaced the pistons and done the sleeves and the first start was yesterday ,
the engine runs but I have 2 problems
1- the engine heats up :- I have but the new coolant liquid in the car stocked it slowly it like in from the reservoir only one , then start the car if I open my A/C the car heats up quickly the water in radiator very very hot the water in the reservoir is cold, I suspected the thermostat opened the thermostat the other very hot there I noticed the small o for the thermostat is not there there is 2 o rings beg one and smaller one ,
now I don't know if I'm flashing the water wrong or it's bad water pump or it's bad thermostat or it's just the o ring the car took 10 litres ?
second think the car takes long to stars I don't know what I just removed the error codes I think it could be from it but I truly don't know it could be from them or it could be injectors or fuel pressure pump?
cand you help me please guys 🙂
Thank you

mbwillgrubs

First thing I would do is back up and check compression. That will have you looking at the plugs for clues such as fouling and water ingress. That would give me insight into the hard start problem and insure I am not getting water past head gaskets. You could also use a OBD II reader to monitor fuel pressure and see if you are setting codes.
With respect to the coolant; is it overheating? The o-rings you speak of, if you posted a picture there are some talented folks in this group that could give you insight into what might have gone wrong.
Just be patient and methodical. Good luck.

Hector 313

thank you very much for your reply, yes its overheating especially when I start the as the heat jump for the picture you can check the attachment it's the origin that I meant