That fluid is somewhat costly, i think i would verify that the pump is at least circulating fluid when the engine is running by removing the cap on the reservoir and look in there, if its working you will see a small stream of fluid coming in from the small steel return pipe that attaches to the cap. Then do your cleaning and leak finding and after the repairs are made flush and fill with new fluid.No point putting in the new fluid then having to take the system apart and loose half of it. Don

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Red Green "This is only temporary,Unless it works!"

97 E300D 157000 miles
87 300TD ?141k? miles