1.) Doesn't the container have the instructions on it? 2.) I'm thinking running the citrus solution for 15-30 minutes would suffice. 3.) You should flush the system until the water coming out runs clear. Don't drive around with just water in the sysyem.
Why is it not practical for you to not be able to open the drain on the block? It's right there on the passenger side by #5 spark plug. A 19mm wrench will do the trick. Of course, if you don't have the tools or a suitable location to do this I understand.
However, I really don't understand why your mechanic can't do it. If he can't, you need a different tech. Draining the block is one of the easiest things to do. You simply loosen the plug and let it drain. The radiator is the same proceedure
91 300E 120K
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