Magic coolant loss? - PeachParts Mercedes-Benz Forum

kaoskingnd · #1 07-28-2007, 12:52 AM

Today I almost got all the filters replaced and will flush all the systems this weekend, but I am loosing coolant fluid really fast and I have checked every hose and connection. I loose about half the res every three or four days, but it does not show up anywhere. Plugs are fine no coolant discoloration. I keep hearing about a mono-valve could this be a culprit. I am completly stumped.

t walgamuth · #2 07-28-2007, 05:30 AM

There are only two ways for it to be getting away. Either out the tailpipe from a blown head gasket or cracked head or block, or it could be leaking out when the car gets hot and then the passage out seals back up when it cools down.

If it is the first that is somewhat expensive problem. In that case you should see some steam coming out the exhaust and be able to smell a sweet smell from the exhaust. Steam vs smoke will dissapate into thin air shortly after exiting the exhaust pipe.

If it is losing coolant you should be able to find some leaking out somewhere when you park the car after driving it and getting it good and hot.

Good luck

Tom W

sbourg · #3 07-28-2007, 12:47 PM

Get a coolant system pressure tester - pretty reasonable at Sears - and pressurize with the engine cold, but running. Look for coolant dripping. If necessary, test with engine off, but if you have a blown head gasket, you will get liquid coolant filling that cylinder - not good.

Steve

LUVMBDiesels · #4 07-28-2007, 03:10 PM

If you have a W126, check the hoses between the two walls. I was loosing coolant from the hoses near the aux water pump and the Monovalve.
you don't see the coolant on the ground because it collects in that area.