Hi, I have recently bought an 1983 MB 300D Turbo. The heat hose to the firewall is disconnect, because of suspected leak in the heat core. I wanted to know if I can connect it back, and pour a sealant in my coolant so it can seal the leak?

Over the ‘many’ (44) years I have been doing auto repair - I’ve yet to find any sort of ’miracle’ products that will be a permanent repair for ANY type of coolant leak or other problems that require mechanical repairs .. I’ve tried quite a few of em - without any long term success! Plus you never know when the leak will return and possibly leave you stranded.. Good luck with it - whatever your endeavor!

I am not looking for a LONG term success, hence I will not be using the heater that much. But I would just would like to know if it will be a good idea to plug that hose back in, and to pour Blue Devils, head gasket sealant in the coolant reservi and see if it will repair the problem temporary. Replacing the heat core is very costly and demanded in labour. My mechanic does not even want to do it, because in his eyes it is not worth it.