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Losing Coolant every 1-2 weeks

2186 Views 7 Replies 4 Participants Last post by  l1tech
Another yell out for help,

My 525i 2004 is starting to turn on rough in the morning for few minutes and will lose about 200-300ml radiator coolant every 1-2 weeks. Guys have done a pressure test and could not find out any leaks. Any suggestions???

Cheers.
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If you can't find a leak you must consider the possibility of a headgasket leak. You could do a compression check and a cylinder leak down test . Pull out the sparkplugs and take a look.
Thanks, and I am new to all this, any idea how to check the headgasket leak without taking it to another mechanic.
One way would be to get at tester that you put over your coolin system to check for gases from the cylinder. It has a chemical that changes colors when gases from the cylinder are present. This is probably the easiest test that you can perform and some times the only test that will find the problem. All that you do is take off the radiator cap , the tool has a rubber stoper that you just hold in place of the cap ,then run the vehicle and watch and see what happens.
same problem

i had the same problem in nov of last year took it to the dealer and they couldnt find a problem same thing in jan when my extended warranty ran out didnt find anything then in march i had to get a new radiator $$1200 bucks!!i was so pissed i contacted bmw of america and they couldonly help me by taking $$600 bucks off the bill..Be very adament make them find the problem..
The 2 symptons together make it sound as if there is a blown head gasket but it is probably so slight that it seals itself within the first minute of running and will almost never shop up on a block test, that's the test that [email protected] is describing . What I have had to do in cases where I suspect this is to have the customer leave the car overnight so I can pressurize the cooling system overnight and have the engine cool down. Next all the spark plugs are removed and then you can look into the cylinders and see which one has coolant in it.
Thanks I1tech, I am planning on valve cover gasket replacement as it seems to be leaking. While I am doing that, is there a way to confirm if the coolant is not leaking into the engine block anywhere?
The 2 symptons together make it sound as if there is a blown head gasket but it is probably so slight that it seals itself within the first minute of running and will almost never shop up on a block test, that's the test that [email protected] is describing . What I have had to do in cases where I suspect this is to have the customer leave the car overnight so I can pressurize the cooling system overnight and have the engine cool down. Next all the spark plugs are removed and then you can look into the cylinders and see which one has coolant in it.
Your not going to be able to see anyting with the valve cover off.
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