Engine Temperature For E30 M40

[rayncc]

Hi fellow members,I drive a E30 with 318i M40 engine. From digging the old threats, I understand that the optimum engine temperature for this car is at the centre (half way) mark.I’ve just owned this car for 2 weeks and noticed that my car’s normal temperature is between the blue zone and the 1/4 quarter mark. The maximum it will go is at the 1/4 zone and not more than that. Suspecting that the thermostat could be faulty, I’ve changed it last week at my mechanic’s shop (Nathan, Selvam’s ex-mechanic, who is now attached with the workshop behind Shell Station @ Jalan Gasing). Unfortunately I did not inspect the temperature rating of the new thermostat. The mechanic had source the part from Bavarian Auto (SS2) so I would believe the supplier, being familiar with these cars, would have supplied a thermostat with correct rating. In the process of replacing the thermostat, the mechanic also added a bottle of original BMW coolant into the radiator.However, the ‘problem’ still persisted as the car’s engine temperature remains the same as before. Personally, I would have preferred to have the engine run hotter as I believe it will gain better performance and fuel consumption.I need to seek advice on the following :-1. Does any fellow members’ car experienced this? 2. Being new to this car, I want to know if this is normal.3. If its not normal, how do I‘tweak’ the engine in order to achieve the centre mark engine temperature. 4. Any other reputable mechanic expert in E30 (preferably Klang Valley or KL area) that I should visit to diagnose the problem and/or carry out the above no. 3.Cheers!!!

 

[dpointt]

dont worry abt it...
it seems tt almost all E30 here are using the same thermostat that gives only 1/4 mark reading
as the climate here i hotter, thus the adjustment has been made!

If you use the actual original ones, the temperature can show in the middle mark but will cross it when u turn on your ignition key without the engine started.... thus may cause a panic, but its just 3/4 reading tt will be back to normal once the engine and coolant started flowing

so the 1/4 thermostat is to prevent the reading to cross 1/2 at all time

though I dont really know if the thermostat is above 3/4 will the engine be able to get started? don bother to know as I am not using this thermostat!!!

hope this helps....

 

[fabianyee]

there are 2 temperature ratings for the thermostats. For the '1/2 way mark' temp, it is 90 deg C rating... The lower temp uses the 80 deg C rating...
FYI, the 90 deg C theromostat is the more expensive of the 2.

I've always been using the 90 deg C thermostats on the M40 and oso the M42.

 

[evilnickwong]

Last time for my car (E30 M40 as well), the normal running position is at the 1/2 mark as well. Then when stationary at traffic lights or something, it might creep towards 3/4.

At one point, I changed the thermostat and after that, it is like yours, the normal position is 1/4. But I did not notice any difference in fuel consumption/performance if anything.

*EDIT* just saw your post fabian.. is there any advantage/benefit using the 90degree one over the 80?

 

[Gerald 5]

I am having the same situation too after changing the thermostat. The car temp was all the while at the centre b4 this.
The story goes like this, was travelling back to KL from Ipoh and the car was overheated. Stop the car at Sungkai, and noticed that the waterpump leaking. Added water and was lucky to be able to travel back to KL. Changed the water pump and the temp was slightly above the middle line and was not very comfortable about it. Mech advise to change thermostat and I did, the thermostat rating was 71. After that, the temp always stay at 1/4 mark and to be frank, I didn't notice any lost of power nor increase in fuel comp. I am no sifu, so I would like also to find out if this has got any negative impact on the engine and it performance? Many thanks.

 

[Gerald 5]

there are 2 temperature ratings for the thermostats. For the '1/2 way mark' temp, it is 90 deg C rating... The lower temp uses the 80 deg C rating...
FYI, the 90 deg C theromostat is the more expensive of the 2.

I've always been using the 90 deg C thermostats on the M40 and oso the M42.

Slight variant as what my mech told me, need to qualify "my mech told me" so, don't kill the messenger. Only 2 variant rating are available 88 c and 71 c.

 

[rayncc]

Thank you guys for the replies! At least it has enlightened me that my car is normal.

On another matter, what is the averaged fuel consumption for these M40 powered cars?

For my last full tank (48litres), i covered 498km on light footed mix city & highway driving.

I must quote that my car has the following features which may negatively affects the fuel consumption :-

1. Ranspeed muffler
2. Performance chip (come equipped in last batch special edition models sold by AB, car labelled as 'Evolution' - read from old threat that its a AC Schnitzer chip. Mine is Evolution car no. 16)
3. 16" rims on 205/50-16 tires

 

[evilnickwong]

My full tank usually gets 450+ km only, but I'm almost 90% city driving and my daily commute to work is only about 6-7km, don't think that's enough warm up and running time for good fuel consumption.

 

[pussy]

Firstly, kindly introduce yourself first in the newbies thread.


secondly, the thermostat that he replaced is the same as the previous one 72 deg. if you want, go with the 88 deg.

 

[rayncc]

Firstly, kindly introduce yourself first in the newbies thread.


secondly, the thermostat that he replaced is the same as the previous one 72 deg. if you want, go with the 88 deg.

Hi Pussy, yes i've just done so..

 

[Gerald 5]

aiyoo, all your consumption so good one, mine full tank all the way to the red light gives me a maximum of 320-340km, so what can be wrong? Changed fuel pump, change vacuum hose and had check all by my mech and still of no solution yet.

 

[dpointt]

498km is a good figure for ur ride buddy....
dont forget that the car is at least 1.5 tonnage, unlike other jap cars!

cheers...

 

[rayncc]

aiyoo, all your consumption so good one, mine full tank all the way to the red light gives me a maximum of 320-340km, so what can be wrong? Changed fuel pump, change vacuum hose and had check all by my mech and still of no solution yet.

Dear Gerald 5,
I must say your car's consumption is very high. Do you drive it hard and always caught in heavy traffic conditions?

When i achieved 498km on my last tank its on a very light footed driving mode. However, now i'm on my second tank and will drive more 'normally' (faster with occasionaly burst of speed). Will report on my car's consumption on this tank later.

 

[Gerald 5]

Dear Gerald 5,
I must say your car's consumption is very high. Do you drive it hard and always caught in heavy traffic conditions?

When i achieved 498km on my last tank its on a very light footed driving mode. However, now i'm on my second tank and will drive more 'normally' (faster with occasionaly burst of speed). Will report on my car's consumption on this tank later.

Nope, I don think so.. the car was bought in Oct last year and had check with the ex-owner and he was getting... well 280km and occassionally 300km... but I have changed everything, even my mech is out of idea.

 

[rayncc]

Nope, I don think so.. the car was bought in Oct last year and had check with the ex-owner and he was getting... well 280km and occassionally 300km... but I have changed everything, even my mech is out of idea.

Are you using the standard final drive? For my car, 5th gear @ 100km/h is 2,950rpm. I believe my final drive is 4.1. Can anyone confirm this?

 

[nawtyboy]

hey Gerald. sori to ask this, are u running on m40 or m20? 1.8, 2.0, 2.3 or 2.5?

my previous ride was m40 1.8, FC suffers like hell...full tank only gets about 250km city moderate driving.

my current m20 2.3 has better FC, it gives full tank 360km with mix city occasional heavy foot driving.

my diff shall be in the region of 3.61 or something...can't recall correctly....

 

[evilnickwong]

I don't think

 

[Gerald 5]

hey Gerald. sori to ask this, are u running on m40 or m20? 1.8, 2.0, 2.3 or 2.5?

my previous ride was m40 1.8, FC suffers like hell...full tank only gets about 250km city moderate driving.

my current m20 2.3 has better FC, it gives full tank 360km with mix city occasional heavy foot driving.

my diff shall be in the region of 3.61 or something...can't recall correctly....

Mine is a M40. What else can be wrong?

 

[fabianyee]

M40 with only 250km range?? that's horrendous fuel consumption. U sure your tripmeter is accurate?
so 1 full tank can't reach Penang or JB?

 

[Gerald 5]

M40 with only 250km range?? that's horrendous fuel consumption. U sure your tripmeter is accurate?
so 1 full tank can't reach Penang or JB?

Refer to my earlier post, I am getting about 320-340km top and you are right, the last trip to Penang with full tank, I actually stopped by at Bukit Merah to top up another RM71 petrol.
RM71= about 40 litre of petrol and the trip meter was showing 294km.