radiator water always reduced (e46 318i)

[viewfinder]

I use the original BMW coolant (blue) which is cheap even if it's bought from A.B.. BMW coolant is supposed to protect the radiator... otherwise I would also run just plain distilled water like you Jarance (distilled water is actually better for heat exchange). Occasionally I also add Water Wetter besides just BMW coolant.

Used to use another coolant by Wurth, which is concentrated navy blue. Occasionally I forgot to remind the mechanic, the shop's standard procedure is to drain & pour in 2 bottles of Caltex coolant (not blue) #@$@*!

 

[astroboy]

.. So AB, what the correct type of coolant for M54 engine?

Dunno le.. I was hoping sifu out there would shed the light on this matter, after all my bimmer maintenance knowledge is all rusted lio after I sold off my E36 10 years ago... now got generation gap If OEM coolant is not expensive, then use OEM ones loo. More importantly its the dilution mix. Get premix ones, then no need to headache.

Fill it up with water for sometime to check for leaks is a good move. Just in case other places got bocor, you won't cry over spill coolant.

 

[jarance]

I use the original BMW coolant (blue) which is cheap even if it's bought from A.B.. BMW coolant is supposed to protect the radiator... otherwise I would also run just plain distilled water like you Jarance (distilled water is actually better for heat exchange). Occasionally I also add Water Wetter besides just BMW coolant.

Used to use another coolant by Wurth, which is concentrated navy blue. Occasionally I forgot to remind the mechanic, the shop's standard procedure is to drain & pour in 2 bottles of Caltex coolant (not blue) #@$@*!

Actually, I use Demineralise Water instead of distilled water. The best part it is FREE.. :rock:

 

[QD250]

i use toyota LL coolant..... hehehe....

balance from servicing my toyota..... AB also uses it for his avanza....

 

[jarance]

Just found out that the most suitable coolant for Aluminum engine is HOAT based.

# Organic Acid Technology (OAT) or Extended Life Antifreeze Coolant (XLC or ELC)
antifreeze contains neutralized organic acids (organic acid salts) that protect engine parts from corrosion. These include Havoline® XLC, GM's Dex-Cool® (also manufactured by Texaco) and VW's G12.
Honda has an extended-life OAT coolant that is dyed dark green and does not contain 2-EHA.

OAT includes such ingredients as sebacate (Toyota & Honda), 2-ethylhexanoic acid (2-EHA) and other organic acids, but no silicates or phosphates (except in the case of Toyota's pink extended-life coolant, which adds a dose of phosphate to its extended-life OAT-based antifreeze).
Organic inhibitors do not deplete as quickly as the inorganic inhibitors used in conventional coolants.

OAT is recommended in engines with aluminum components (heads or radiators) because Borates can be bad for them.
OAT coolants also have extended lives, up to 150,000 mi.

OAT corrosion inhibitors provide excellent long-term protection for aluminum and cast iron, but may not be the best choice for older cooling systems that have copper/brass radiators and heater cores, especially the lead solder used in them. It depends on the formula.

# Hybrid OAT (HOAT) coolants, such as "Zerex G-05®" Use organic acids, but not 2-EHA (2-ethylhexanoic acid) (different organic acids are used). Hybrid OAT coolants add some silicate to provide quick-acting protection for aluminum surfaces. Silicate also helps repair surface erosion caused by cavitation in the water pump. Hybrid OAT coolants are currently used by many European vehicle manufacturers (BMW, Mercedes & Volvo) as well as Ford and Chrysler.

Toyota adds some phosphate to their hybrid.
# The new universal coolants use unique OAT-based corrosion packages with proprietary organic acids (such as carboxylate) to provide broad spectrum protection.

and BMW coolant which is BLUE in colour is HOAT.

 

[astroboy]

Amazing info! What's the conclusion?

Toyota Long Life is pre-mix at RM23.90/L (Last year). My Avanza is running 3L and replaced every 40k km @ RM71.70. Toyota has a Super Long Life which can last 160k km but dunno how much and how to use it..

How much is BMW HOAT?

 

[jarance]

Look like Toyota Coolant fall under the same spec as BMW.. see below chart..:top:

 

[t2ribena]

was discussing this with a fellow member who did a research on coolant for our cars and...

our OEM BMW coolant is of type G48 which is normally blue'ish green in colour...if not mistaken this G48 coolant was a product by BASF which is marketed under their Glysantin trademark...the main diff to the G05 coolant is that it contains no nitrite...G05 coolant (yellow) is normally used for diesel or heavy duty engines...both contains organic acid as bro jarance expained above...G48's PH level is around 7 and G05 is at low 6 which makes it more acidic in nature...

G48 has a slightly higher boiling point than G05 but this depends on the mix...normally for our weather if not mistaken 50-50 mix with water.

IMHO better dun put those coolant from Jap maker as it normally not suitable for european engines in terms of material used and how they cool the engine. Normally jap engine coolant contains silicate and phosphate...

 

[astroboy]

But BMW blue coolant is Hybrid OAT as well la. So they too might have added silicate (repair aluminum corrosion) or/and phosphate (extend coolant life).

Looks like 1st choice is still BMW blue coolant and nearest convenient alternative is Toyota pink coolant, both are Hybrid OAT.

Any seconder to my opinion? SO we can close the topic and move on..

 

[QD250]

seconded.................. hehehehhe...

 

[jarance]

Yesterday, did an inspection of the cooling water as I am still experiencing loss of coolant after 1 week I have replaced the radiator and top hose.

Start the engine after removing the bottom plastic cover.. check everywhere but no sign of water leak. Run the engine idle for about 10 minute and still no sign of leak.

Stop the engine and after 1 minute, there was some water droplet near the right side of the radiator. check further and found the source was from the expansion tank..

Went to BA spare part shop and got a expansion tank for RM200 and coolant (ori) 1.5l for RM32 per bottle.

Took me about half an hour (DIY) to change the expansion tank. Now still monitoring for leak.

Hopefully, the problem could be solved.

Just curious to know why it ONLY start to leak at the expansion tank after the engine is stopped!!!

 

[astroboy]

BMW technology has more than 1 cooling system thermostat, dunno about other European marque but JDM definitely only has 1.

The reason to have multiple thermostat is to allow water in the cooling system to be heated up a little to reduce thermal shock to the engine block when cold water suddenly pour into the super hot block which will cause abrupt shrinkage of the block and cause more wear and tear to the piston ring. So the thermostats operate at different timing.

After the engine is heated up for about 10 min, the first thermostat will open allowing the water into the radiator to regulate its temperature before the 2nd thermostat open, allowing the now heated water from the radiator to flow into the hot engine.

When the first thermostat open, water in both expansion tank and radiator will be heated up, and pressure increases while the second thermostat has yet to open. Thus the building pressure of the heated water will stress the expansion tank out and its design to break as collateral damage to protect the more expansive radiator when 2nd thermostat fail to open. During this time, its when Jarance notice the leak. 2nd thermostat either has shut or has yet to open.

BMW engineers are determined to protect the engine, so extra works, hoses and parts are designed for the cooling system. All these are adding to the cost of building the car. The engineers who build the car and engine are like with budget in their least priority. So end up with 4 O2 sensors, 2 catalytic converters, 2 thermostats and perhaps few others "redundant" parts like the intake flap in the diesel engine that fail and drop inside the combustion chamber. The flaps can be deleted and car engine still runs fine.. :stupid:

 

[flash]

Had that same "issue" with my ex-E36. Was losing water, not much, but of a concern nonetheless. Did pressure test but found nothing. Ran the engine, tried to look for leaks, zilch, nothing. Turned the engine off, left the engine to cool down for further tests. Then it happened, when the engine had cooled down, the car started to "piss" its coolant. Found the damn leak from the temp sensor... and we found that when the car had cooled down. Still wondering why we could not trace it with a hot and running engine.:stupid:

Just curious to know why it ONLY start to leak at the expansion tank after the engine is stopped!!!

 

[jarance]

Had that same "issue" with my ex-E36. Was losing water, not much, but of a concern nonetheless. Did pressure test but found nothing. Ran the engine, tried to look for leaks, zilch, nothing. Turned the engine off, left the engine to cool down for further tests. Then it happened, when the engine had cooled down, the car started to "piss" its coolant. Found the damn leak from the temp sensor... and we found that when the car had cooled down. Still wondering why we could not trace it with a hot and running engine.:stupid:

Thanks flash for your recount.. Now found a way to check for leak.. :top:

 

[chetz]

WTA - radiator water tank cost

How much this unit cost?? any seniors here change this unit before? lately i found that my radiator indicator blink once awhile.. i top up the water level and it runs ok.. few days.. it happens again.. took my 46 for inspect and find out the water tank leaking.. wanna know how much the cost of it.. quoted 2++ by foreman.. pls advice me.. thank you~

 

[jarance]

The expansion tank is selling for Rm200 at Bavarian Auto.

 

[ICEMAN 68]

Had that same "issue" with my ex-E36. Was losing water, not much, but of a concern nonetheless. Did pressure test but found nothing. Ran the engine, tried to look for leaks, zilch, nothing. Turned the engine off, left the engine to cool down for further tests. Then it happened, when the engine had cooled down, the car started to "piss" its coolant. Found the damn leak from the temp sensor... and we found that when the car had cooled down. Still wondering why we could not trace it with a hot and running engine.:stupid:

reason of not tracing the water leak when the engine is hot , could be due to the plastic material composition of the rad ...it may had been made by ABS or high graded polycarbonate plastic ...therefore when it's hot the material tend to expand due to the heat or presure and in this case a hair line crack may get closed up ...and when it cools down the reaction of water and the plastic cools down further and cause the hairline crack to open up and harden ... here is when the water start to leak ...

just my 2 cent

 

[Vroom325]

iceman, donno the cause of it, but I just wish to share that it can't be PC or ABS, they are not use under the hood coz of heat & chemical attack(especially PC). Normally Nylon, PP, glass fibre reinfornced plastic, hi grade engineering plastic will be used..

 

[ICEMAN 68]

iceman, donno the cause of it, but I just wish to share that it can't be PC or ABS, they are not use under the hood coz of heat & chemical attack(especially PC). Normally Nylon, PP, glass fibre reinfornced plastic, hi grade engineering plastic will be used..

agree with you , but then we would not know that was it moulded with 100% virgin material OR with a 80/20% recycle material ... sometime when we purchase a new rad we would see it's black shinny surface at first and whereby upon using it for a couple of month the shine tends to be lesser ...

these days a radiators life span that's moulded with PC reservoir could barely last 2~4 years ....

just my 2 cent again

 

[chetz]

Hello seniors.. just did mine today..
changed these unit :-
1- Expansion Tank
2- Thermostat

Solve the leaking and overheat prob.. but another prob occur.. car will overheat if i turn on air cond.. foreman said it could be the radiator fan relay problem.. anybody experience this before?? car will overheat if using air cond??