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Fraz06
06-20-2007, 03:15 PM
Hey guys, I bought another 520i with the m20 engine in it as a project car and the previous owner must have put to much coolant or water into the cooling system when they changed the coolant because i have water coming out the tailpipe with sum white smoke, how would i get this sorted out and running the way it should?

thanks guys

Fraser

DaveVoorhis
06-20-2007, 04:01 PM
The coolant mix and amount has absolutely nothing to do with what comes out the tailpipe.

Unless, of course, you've got a failed head gasket. Does the exhaust smell sweetish? Does the coolant level in the rad drop when the engine's running? Strange temperature gauge behaviour? Does your oil look like a chocolate milkshake? If the answer to these is "yes," you've likely got a failed head gasket.

Otherwise, it might simply be normal moisture content in the exhaust, or even rainwater that's blown in while the car was sitting. If you don't have symptoms of a blown head gasket, drive the car until it's well warmed up and then check for water and steam coming out the tailpipe.

repenttokyo
06-20-2007, 04:19 PM
White smoke that doesn't go away = bad head gasket.

Fraz06
06-20-2007, 05:43 PM
Hi thanks for the reply, when i turn the engine on the engine is running for about 30seconds or so there is hardly any smoke at all and then about a minute later there is lots of white smoke coming out of the tailpipe, and when i gently rev the engine for about 30 secs there is lots & lots of white smoke coming out of the tailpipe and it really smells, the white smoke gets worse when the engine is at normal temprature, Does this sound like a failed head gasket?

thanks guys appreciate all your help

Fraser

DaveVoorhis
06-20-2007, 05:46 PM
That sounds like a failed head gasket. Check the oil for the presence of coolant. Check the coolant for the presence of oil.

Fraz06
06-20-2007, 06:02 PM
Hi, Just been out to the garage and can't find any oil in the coolant or any coolant in the oil.

Paul in NZ
06-20-2007, 06:07 PM
on the other hand these cars do produce lots of condendsation from the tail pipe,and for a long time.You dont say where you are from so for all we know it may be the coller air that is making the normal moisture visible.If you only do short runs the exhaust will never get hot enough to drive the moisture out so you see water dripping out the exhaust...so it can be normal!

DaveVoorhis
06-20-2007, 06:12 PM
Does the coolant level drop while it runs? From the description, it sounds like a headgasket failure, even if coolant and oil aren't mixing. Does the exhaust smell sweet, or does it smell like burning oil or petrol, does it smell like rotten eggs, or does it smell like normal exhaust?

And, as Paul in NZ said, it could be normal if you've not run the car long enough to boil off the condensation.

Ross
06-20-2007, 06:12 PM
Pull the spark plugs. If one is squeaky clean, then coolant is in that combustion chamber and either the head gasket has failed or a cracked casting.

Fraz06
06-21-2007, 06:55 AM
The coolant level drops while the engine is running and the exhaust smells like something is burning also when the engine is running for 15mins the needle on the temp guage is 3/4 up to the red part of the guage.

DaveVoorhis
06-21-2007, 07:01 AM
The "exhaust smells like something is burning" doesn't tell me much. Does it smell like fuel, oil, or sweet like antifreeze?

However, the coolant level dropping and the high temperature both point to head gasket failure.

Fraz06
06-21-2007, 03:21 PM
Thanks for everyone's help guys really appreciate it, it smells like burning fuel,