1998 328is cooling issues

[328Marcos]

hi all...
so Ive got some questions for you all, i cant see the coolant flowing in my tank and my hoses are not under pressure of any sort. i tried bleeding the system but still no flow seems like the coolant is just sitting there. my dash temp gauge stopped working a long time ago, so i installed a after market gauge. its the kind that you splice the upper hose, install a sending unit adapter. temp reads off the upper hose. it was working just fine, now it barely moves. Im thinking that the coolant is not warming like it used to, What does this sound like to you?

[Lord Vader]

Not sure why you installed a second gauge when you could have replaced the temperature sensor under the intake manifold and it probably would have fixed it.

What's the history of the cooling system? Has it ever been serviced? If not, I would say your definitley due for an overhaul. The cooling system in the E36 is a weak point. I recommend that you get a new thermostat, aluminum thermostat housing, new water pump with metal impeller, new radiator hoses, and inspect the fan and fan clutch for wear and replace of nessecary. Also check the coolant expansion tank for cracks.

Also, check your oil. Make sure it's not a milky white.

[328Marcos]

got new water pump and thermostat wanted to replace being that dont know when they were replaced last. pump was ok, but still old. thermostat was my issue, took off housing and out came a couple pieces, thermostat was letting water flow free.

[Lord Vader]

Awesome. Good to hear you fixed it. Did you replace the thermostat housing too?

[328Marcos]

yes... Vader, I wanted to ask you if you new the actual temp of operating temp of these engines?

[Lord Vader]

The OEM BMW one is a 92 degree thermostat. Anything lower like the 88 ones is not recommended. The OEM thermostat isn't very much and is recommended over aftermarket ones.

[Jack Dabsy]

Not recommended by BMW, Vader?

Viscous fan delete + a 70deg thermo with a leccy fan gives another 5+hp

[Lord Vader]

With the fan delete running a different thermostat is obvious. I wouldnt do it here. Too much temperature variation. -40 to +40C is possible in the same month.

Several people have told me that its not recommended on the E36 to run anything less then 80 degree thermostat unless you have the fan delete. The TIS, nor the Bentley mention the actual temperature range recommended. I personally prefer to use OEM or OEM Manufacturer parts. If they lasted 13 years already, why sub in an aftermarket one?