Got a mystery coolant loss on the m60.

[yy101]

Just had to fill up the expansion tank this morning...seems to be about 1 ltr. I drove it about 650km in one day and the next morning had to refill, and last week I drove it about 100km in about 5-6 days and had to do the same.

Its not going to the engine since I checked the oil and its not milky white...or blows white smoke. And it runs good.

But now I cant see any external leaks/pool of blue fluid under the car even straight after turning the ignition off and plonking the bonnet up, except the first time I noticed it at a car park and it seems to pooled directly under the rear of the engine, rob101 can verify that.

I have just recently replaced the aux water pump for the heater core, and have moved/stirred/disturbed the hoses around the aux water pump/solenoid valve assembly.

Any ideas, whats the most common m60 coolant leak? I am getting that lovely sweet syrupy smell every time I run the car and open the window or door, so I am pretty certain the leaks external and must be falling onto something hot and evaporating straight away, hence no coolant pool.

[zekgb]

Had the exact same symptoms at 200k, turns out the bottom of the expansion tank had developed a series of cracks that allowed the coolant to weep out, requiring a top off every few days.

[yy101]

Had the exact same symptoms at 200k, turns out the bottom of the expansion tank had developed a series of cracks that allowed the coolant to weep out, requiring a top off every few days.

Thanks moite, sounds like my gremlin...hmm think its e34's way of saying it loves me, wants me to get busy with it under the hood lol...

[Antrieb]

http://realoem.com/bmw/diagrams/c/k/3.png

Part 4 and 6 run the length of your engine delivering coolant to the rear of the engine. Your O-rings need to be replaced (part 7 & 5).

[Fetch]

Part 4 and 6 run the length of your engine delivering coolant to the rear of the engine. Your O-rings need to be replaced (part 7 & 5).

nice, I like how you think.

Also, maybe try looking for that white crusty stuff dried up coolant leaves.

[yy101]

Will take a look at it tmr, gonna open her up!

[av8r]

I had the same problem and it was the coolant tank. It had developed a crack where it hooks onto the firewall. I bet if you take it off you will see it.

[Rus]

I've had a strange loss of coolant for a while as well and just today noticed that there is some seepage from the lower connection of the expansion tank. In one of my brilliant moments I placed the clamp in the wrong place and it didn't seal properly. Check those simple things first :)

[zman-95-540i]

+1. I recently had the same problem with my expansion tank (167k miles).

[mattyb]

the most immediate suspect is always the lower round plasitc insert at the bottom of the expansion tank. it is practically unfixable (read totally) and is the only serious flaw with the vehicle. I have kept my old radiatot to have a friend fabriacte a stainless steel tank for the next time it goes. dont bother trying to fix it you have to get a new one. dealer prices starts at $850 au. Even the ones they supply now have the same flaw and upon replacement my new one lasted 6 months before doing the same thing. had it repalced under warranty and no probs since. Examine the surface area of the expanasion tank facing the engine. often it appears that a hose is lose or fragile. this is an error ussually and closer observation of the suspect area will show the round moulding to be weeping.

Best of luck. if it this it only gets worse until you replace it. no matter how much goo you can get onto it as a partial fix.

[yy101]

the most immediate suspect is always the lower round plasitc insert at the bottom of the expansion tank. it is practically unfixable (read totally) and is the only serious flaw with the vehicle. I have kept my old radiatot to have a friend fabriacte a stainless steel tank for the next time it goes. dont bother trying to fix it you have to get a new one. dealer prices starts at $850 au. Even the ones they supply now have the same flaw and upon replacement my new one lasted 6 months before doing the same thing. had it repalced under warranty and no probs since. Examine the surface area of the expanasion tank facing the engine. often it appears that a hose is lose or fragile. this is an error ussually and closer observation of the suspect area will show the round moulding to be weeping.

Best of luck. if it this it only gets worse until you replace it. no matter how much goo you can get onto it as a partial fix.

Its the "06 WATER HOSE INLET 3 17221728943 $70.59 ".

http://www.realoem.com/bmw/showparts.do?model=HE62&mospid=47384&btnr=17_0086&hg=17&fg=05

Its weeping around the crimp connection in the middle.

Matty, I got a quote from BMA and this is what they charge - "Expansion Tank - 17 11 1 719 110 - $56.25"

[yy101]

Anyone know the length and pressure rating of that hose? I am going to get Pirtek or Enzed to make them to suit, and I havent been able to find information about the hose. I want to make a replacement up before taking my old one out.

[632 Regal]

be prepared to deal with corrosion on the aluminum manifold. Mine was real bad and getting a wire wheel in there is tricky. took me hours using acid and avery small brush and then baking soda solution.

[mattyb]

ah grasshopper, beware that some tank seam do not crimp again and not recommended!! but hell give it a try beats the **** outa 900 bux for a palusable fix.

let me know how it goes!

[yy101]

ah grasshopper, beware that some tank seam do not crimp again and not recommended!! but hell give it a try beats the **** outa 900 bux for a palusable fix.

let me know how it goes!

Its not my expansion tank thats leaking, I have found my leak on the water inlet hose to the transmission oil cooler, one end is a standard hose fitting w/hose clamp and the other is a threaded female with o-ring. The leak is actually in the middle where it appears to be a crimped fitting joining two lengths of hose. Its weeping right now, not too bad.

Anyway I cant believe the price difference, between what they charge here and what we can get from BMA. There is a big difference between 850 AUD and 60 USD for a plastic coolant tank. And the replacement hose is only gonna cost me 48 USD plus shipping. Not even gonna bother getting a quote here.

[rob101]

Not even gonna bother getting a quote here.

You understand now....