I had the same problem. Apparently I'm told it's a common complaint with 190 E's. It is because the coolant sensor (found in the front of the cylinder head) doesn't come in until the engine is touching 110 degrees. The oil pressure drops, revs drop, and panic sets in.
If you have a haynes manual look at: Carburettor fuel system, page 4A.10 and look at the diagram it should give you an idea of where the sensor is(you'll see the two prongs clearly visible).
I fitted a switch in the dash so I could switch it on manually at around 80-90 degrees to alleviate this.
To test the fan is working, all you have to do is bridge the two prongs on the sensor with a piece of wire (one piece of wire and put either end on each prong)and it should turn on to high speed (you'll hear a click). Then get some advice on how to fit a switch. It's not that difficult if youv'e got the patience and a few brains to pick. If you need any more help email me at email@example.com
I don't have a wiring diagram, sorry, bat as to the overheating: it sounds like your thrmostate isn't opening--did you replace it along with the rad? Take the old one out and put it on a pot of water on your stove. It should open around the boiling point of the water--if not, you need to replace it. If it works, you may have a water pump issue i.e. your pump is not circulating the water/antifreeze. The only other problem would be the fan not working, but that would only be the problem if you are driving in quite hot conditions and sitting a lot in traffic.
Another way to find out if your thermostat is failing is to run the car for five to ten minutes and touch the lower radiator hose. If the lower radiator hose is cold then your thermostat is busted. This may sound stupid, but make sure there's coolant in the system and no major leaks before you try this test.
OVER HEATING 190e V.P.RISI
To prevent over heating remove the thermostat damage THE thermostat so the bottom port that the thermostat closes remains blocked this will force the pump to circulate through the whole system and shut off the bypass.
The electric fan is a little tricky (DISCONNECT THE BATTERY POSITIVE TO PREVENT EXPENSIVE DAMAGE). REMOVE THE AIR CLEANER. Trace the wire going to the Electra magnetic FAN coil below the water pump it has a in-line male female plug under the air cleaner unplug it tape up the wire going to the computer IMPORTANT. TO TEST hot wire the lead going to the fans Electra magnet you will hear and see the fan magnet click in.( DO NOT PUT POWER ON THE WIRE COMING FROM THE COMPUTER) now the circuit must run via a cut in sensor which is the red insulated brass sensor with 3 wires close to the thermostat housing on top and in front of the cylinder head. unplug the 2 connectors attached together this is your on off switch leave the single lone wire in its place. connect a wire using a 5 amp in-line fuse from the battery to the ONE SIDE OF the sensor using a slide on clip the other wire is from the Fans magnetic coil connect to the other side of the sensor they are now in the same place of the removed two prong plug tie the disconnected plug out of the way leave the old two prong plug disconnected. this completes the new Electra magnetic fan circuit the fan will cut in around 90+and out at 85 degrees on its own new powered circuit.
NOW MOST IMPORTANT your car will not start you have to fool the computer you have taken the fans Electra magnetic coil out of circuit AND IT MUST BE REPLACED you can do this using any 12 volt DC solenoid the wire you disconnected that used go to the fans Electra magnet must connected to the solenoids COIL and the solenoids most be well attached to the body work. your car will start and run with no over heating problems.
Blown head gastet, radiator leaking, thermostat needs to be replaced Blown head gastet, radiator leaking, thermostat needs to be replaced
Is your fan coming on?
I'm not a mechanic but, I had to replace my radiator to fix the overheating problem on my 1994. That was the last thing I replaced after replacing the water pump, thermostat, and replaced my fan with a clutch fan. have not had anymore problems with it overheating once the radiator was replaced. Flush the coolant first then replace the radiator. Hope this helps.
your thermostat is closed. needs to be replaced. inexpensive part but can save your engine from overheating.
Inoperative radiator fans, bad water pump, failed headgasket?
Water pump defective.
Ingeneral, the fan will run only if the temperature of the radiator is above the normal range. If the fan is running, then the radiator must be over temp unless the radiator fan thermostat or it's relay is defective. If the radiator truly is over temp then you have a larger over-heating problem You state the thermostat was replaced. if you replaced the fan thermostat then either the radiator really is over temp and it is doing what it should, or there is a problem with the thermostat-fan relay or switch. If you replaced the engine thermostat that controls the flow of coolent between the engine and the radiator, then that probably wasn't your problem and you should look elsewhere for an overheating cause. I would start by determining if the engine actually is overheating or not. If it is, I would look for coolent system problems like the engine thermostat (if you didn't replace it already), water pump, leaks, scale build up in the radiator, or blockages in the system. If the engine isn't overheating then I would consentrate on the fan, fan thermostat and relays.
Waterpump, thermostat, radiator, radiator hoses.
The top radiator hose is above the thermostat. If the top radiator hose is hot, the thermostat is opening. The thermostat is not the problem. Perhaps the radiator is clogged up or the water pump is bad. Look elsewhere.
If you have replaced the water pump then flush the radiator with CLR also check to see if the fan is working properly.
Could be the thermostat or water pump. Check the radiator for crud buildup (bugs, leaves, road trash)
I had replaced the water pump and radiator. This had continued to overheat but not as bad. After replacing the head gasket it was finally fixed. I was able to answer my own question only after replacement.
radiator fan, head gasket,
Could be a collapsed lower radiator hose, perhaps a bad thermostat.
Well ive had the same priblem. We have got new radiator and cap. Then replaced thermostat then water pump. No more problems.
possiable head gasket
Have flushed complete cooling system replaced water pump radiator thermostat clutch fan added 2gal straight anti freeze then filled to capacity with water and truck is still over heating. What else could possibly be wrong
After 10 years radiator may be plugged or restricted - try to flush or boil out May need replacement
the thermostat will be under the THERMOSTAT HOUSING, which is where the TOP radiator hose fits on ie(radiator to thermostat housing) this keeps the engine at an OPTIMUM temperature BUT can be A cause of OVERHEATING IF malfunctioning
can the gasket go bad behind the water pump houseing
my 1993 Toyota Camry radiator had a hole in it it was overheating. I replaced the radiator. The car is still overheating where is the thermostat located. First, drain your coolant from the radiator. Find your lower radiator hose and follow it to the metal housing. This is the thermostat housing. Remove the 2 nuts with a 10mm wrench. Remove the thermostat and replace with new one and new gasket. Re-install and re-fill your radiator with new coolant. Drive the car with heater running. Allow the engine to cool and top off the radiator. Add coolant to the reservoir to halfway between Full and Low.
If you do not have any external leaks, a head gasket is most likely.
A Nissan Frontier may be overheating because the radiator is cracked. A thermostat failure can also cause it to overheat.
Check the fan clutch, it may not be working properly.
Probably the thermostat stuck shut.