E30 Zone

I have a couple of cooling/heating queries, and I'm not sure if they are related:

Situation - bought my 89 318i touring with no history (felt a bit brave!). On the way home, found out there wasn't a lot of coolant in the system as it rapidly got hot , so stopped and let everything cool down before topping up with some Evian (it was the August bank holiday and was nowhere near a garage).

Got the car home, topped the coolant back up, car ran fine although the temperature gauge now seems to settle around the first quarter mark when I am moving along, with brief forays towards the half mark when sat in traffic.

Used for a couple of weeks, coolant level appeared fine. Booked it in to have the cambelt and water pump changed as a precaution and mechanic told me that not a lot of water came out when they opened her up.

Also, while the heater blows hot, it doesn't appear to be very hot - in the current weather this doesn't worry me, but come winter I may appreciate a bit more warmth!

My friends identical touring (same age, same engine) seems to run with the temp gauge at the half mark whatever he does.

What level should my temperature gauge read normally? Is my car knackered? Do I have a blockage?

Usually running around half on the gauge is the norm.

So has it not altered since the garage did the belt & water pump and filled it with the correct amount of coolant?

Yes, no difference after the belt and pump were done. Still on the fitst quarter mark

stickey T'stat maybe??

the 318i i own runs at 1/2 as well as the 316 e36. are rad or fan new ish on yours? i have owened a few 4 cyl e30's some of them have run at 1/4

This could be typical of my luck if it is the thermostat- Mr Haynes seems to imply it could be this as well and declares its a coolant out and fan off job - and I've only just got it back from having the cambelt changed.

the in car thmostat is no linear, so the middle section between the lines only represents a few degrees. as the thermostat is mechanical then there can be a few degrees of variation which translates to a slightly different in car reading.

To change the Tstat is easy and only needs the housing and hoses removing, you will only loose a little water.

are you sure the system is bled of air before you start pulling things apart? And dont forget to bleed with the heater turned fully to hot.

sorry i re read to see its a four pot. thermostat can be removed with only a screwdriver, not required to touch to fan, but you will loose about half the water

Can I double check where the thermostat is? Is it below the fan on the front of the block? Would I get to it from underneath?

it is a small metal thing about a tennis ball size with three pipes going to it visible when looking from your drivers side inbetween engine and radiator.

remove the jubilee clips on all pipes and remove the unit.

to roughty test you need to measure the edge of the pipe down to the valve when cold using a striaght ruler, then remeasure when submergerd in boiling water. it should open by about 7-10mm when boiling hot

I found another topic about low temp where Brian said what is more important is that it gets up to normal temp quickly.

Presuming that the first quarter is my normal temp, how long should the engine take to warm up to normal?

Or is that like asking how long is a piece of string?

on a normally warm day, say 20-25C it should be warm by about 2-3 miles of normal city driving, or 3-5 mins