coolant fluid is gushing out from the radiator cap area when engine gets warm. Cap seems to be just fine, this happened all of a sudden AFTER I bought the car?? Any suggestions ? 91 500 sl with 93k miles...thermostat ? pump ? clutchfan? fan is ran off of belt and when shut off, fan will turn with no problem--bon't will not spin freely.. JUST had my powersteering pump replaced Friday and now this....

I don't know what your problem is but I will say one thing. Its always the thermostat. By that I mean that I would not consider fixing an overheated condition without replacing the thermostat. They are easily damaged by an overheat and are cheap so why take a chance. No matter what the problem was, replace the thermostat anyway.

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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

You didn't mention the temperature gauge?

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2012 E350
2006 Callaway SC560

temp gauge slowly goes up, went up to about 215 or so according to gauge--gauge only goes to 220 then shows red after that....so I shut off car

The old wive's tale is that thermostats fail in the open position.

That has not been my experience.

Follow Steve's advice and replace the thermostat first.

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2012 E350
2006 Callaway SC560

I'll have someone swap thermostats first, I wen't to take the thermo housing off, 2 of the 3 bolts are Absolutely tough to get to, 1 bolt does not want to turn, so I'd rather let a mechanic do this job properly before I screw up and mess up the bolt head. I found the prices for water pumps.
Laso--$152.82
Hepu-$151.00
Graf--$124.90 free shipping on either brand

What would be a reliable brand

Just wanted to update: Found the problem to be the RESERVOIR TANK, surprisingly under the cap (where that meets the plastic tank--it cracked some, ordered a NEW tank for $79. thanks for all the help