I just changed my thermostat in the 1988 300E. I had to rip it out in pieces as it was so stuck in there it would not come out. Anyway, once back in the engine coolant temperature rose to its normal point, at about 82*C to 85*C. Great. Then the hose to the thermostat housing cover popped off and coolant shot all over the place. When I looked carefully at the hose, it has a counterbore for the thermostat housing cover nipple (a black plastic housing cover with integral nipple) and a white plastic reinforcement behind that (down the hose) that starts flush with the end of the counterbore and extends for an inch or so down into the hose, toward the radiator. Anyway, the connection was a very loose fit and when I tightened the hose clamp it did not do much. I tried moving the hose clamp further toward the thermostat housing and that did not solve the problem either. So I put the clamp back on the indentation in the hose where it had been for God knows how long, tightened it with a 7 mm wrench and now it seems to hold. Anyone know what the deal is with this connection? What is the hard, white plastic interior hose liner for? Thanks, Jim

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Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)