ML430 cooling issues
#1
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1999 ML430
ML430 cooling issues
Good afternoon gentlemen!
On at least 3 occasions recently my '99 ml430 (299k miles) has had bubbles coming from the expansion tank which resulted in all of it pouring out on cement. I should point out that the temperatures never went past 100 degrees Celsius and the expansion tank cap still clicks tight. I haven't made time to go to the dealership to get some coolant, so I used water after the first leak.
Long story short I parked the car as it would not be smart to keep driving that way. I highly suspect bad hoses as the water level will go down over night.
Worse case scenario, it is a bad head gasket. Can any one of you provide me with a diagram of the cooling system?
I have some DIY experience doing my own brakes, control arms and other little things.... but i've never dabbled with the cooling system/engine.
Cheers
On at least 3 occasions recently my '99 ml430 (299k miles) has had bubbles coming from the expansion tank which resulted in all of it pouring out on cement. I should point out that the temperatures never went past 100 degrees Celsius and the expansion tank cap still clicks tight. I haven't made time to go to the dealership to get some coolant, so I used water after the first leak.
Long story short I parked the car as it would not be smart to keep driving that way. I highly suspect bad hoses as the water level will go down over night.
Worse case scenario, it is a bad head gasket. Can any one of you provide me with a diagram of the cooling system?
I have some DIY experience doing my own brakes, control arms and other little things.... but i've never dabbled with the cooling system/engine.
Cheers
Last edited by TheNewStandard; 01-09-2018 at 02:51 PM.
#2
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Another very strong possibility is that the tank itself is cracked. It is yellowing just like my wiper fluid tank was (Which eventually cracked) so i replaced it.
I won't be able to check until tomorrow
I won't be able to check until tomorrow
#3
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Hopefully you are not using GREEN coolant. The overflow hose on the tank directs coolant to the ground. Don't go to the dealer, just buy Zerex G05 coolant full strength or already mixed 50-50.
You should first think about changing the thermostat.
If that doesn't do the trick, then buy Blocktester to see if the head gasket is blown.
http://www.blocktester.com/store.htm
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Hopefully you are not using GREEN coolant. The overflow hose on the tank directs coolant to the ground. Don't go to the dealer, just buy Zerex G05 coolant full strength or already mixed 50-50.
You should first think about changing the thermostat.
If that doesn't do the trick, then buy Blocktester to see if the head gasket is blown.
http://www.blocktester.com/store.htm
I'll go ahead and follow your advice, it makes sense. While i'm at it i'm also going to change the expansion tank and FOR SURE the cap. I thought the fact that the cap clicked was a sign that it was still doing its job. Boy was i wrong. Upon a brief closer inspection this morning, i found fragments in the expansion tank. They were the plastic bits and the spring that fits in the inner housing of the cap.
i'll keep you guys updated within the next few weeks once i get the new parts including the thermostat