16v runs cooler with the a/c on
 

hi
this is a weird one see if anyone can help

its a 86 190e 16v, when at ilde or in traffic it runs hot,
it doesn't overheat because I don't let it. Hot is 100.
when i notice its at 100 i turn on the a/c and it dropps
back to 75 very quickly on doesn't rise agian?
If the a/c goes off it risies back up fast?
I just changed the fan clucth ,water pump, radiator, im also running like 80 water and 20 MB antifreeze with water wetter.
it seems to help alot
thanks
dave

190e 16v
Iroc 911
gyrocopter

That's a no-brainer. Your main fan switch never starts. The reason is your auxillary fan always runs when your ac is on. Your main fan kicks in at about 110C and stays on until your temp goes down to 100C. So, when you turn your ac on your aux fan starts and cools the engine down. Now, since 190's use 100-110C switch ("starts at 110C stops at 100C") you actually never give the switch/main fan a chance to do it's job. If you don't believe me, ask any MB dealer mechanic.

Now, if at an idle your engine temp exceeds 115C, your switch is probably bad (it's about $22.00). I have a 1996 Stang, and the temp continuously oscillates between middle and about 2/3 of the gauge, so 110C for a 190 is an equivalent and it's normal, and, I believe, it's not "too hot".

By the way, tkamiya-190s have only one auxillary fan in front of the radiator, and one main behind it. So, no "low speed" fans...

yup

the temp switch is working for the main fan and it does come on at 110 i tested it, but in my driveway i can watch it climb to almost over heating if i dont rev it ? at what temp should the elecrtic fan swith on it seems to only come on with the climate
controll

Actually, the "low" setting of the auxillary fan and the electromagnetic fan are both triggered by the freon pressure switch on the A/C drier. The 'high" setting of the auxillary fan is triggered by the temperature sensor in front of the engine. If you are running your 16v without A/C, both fans have to be triggered at temps above 100 degrees C.

*(100 deg C for the Elect. mag. fan and 110 for the Aux fan @ high: Red 3 prong switch for 16v)

*(105 deg C for the Elect. mag. fan and 115 for the Aux fan @ high: Green 3 prong switch for the 8v)

There are times that having your aux fan run at least on "low" actually prevents the temp from reaching above 100 degrees C to trigger your "highs".

I agree that 75 degrees C is a bit too low.