Reply To: Blocked engine block

Thank you all for your advice.  A recipe on the internet proved effective.  Drain the radiator. Dissolve a dishwasher tablet in hot water and pour into the radiator and top up  Run the engine until it is warm and drain.  Flush with clean water. This is a degreaser and does not froth up.  Use 10 -13 ounces of citric acid per gallon and dissolve with water.  I found got water dissolves the best. Pour into the radiator and top up.  Run the engine until it is hot and let it run for 10 – 15 minutes.  Drain and flush out with clean water until there is no trace of the bitter taste of the acid.   Prior to doing all this I used a drill bit and screwed it into the drain hole, turning it with my fingers. and managed to get a lot of black sediment out.  This was not quite long enough so uses a hard plastic tue sharpened to a point and continued pushing and twisting until eventually water started to trickle out.