Oil in coolant question

[M20power93]

I just replaced my headgasket and in the coolant hoses there was the milkshake like mixture. I let my car idle and ran a hose into the resivor until the water came out clear. I took it for a drive and when i got back the coolant was dirty again with particles floating on the top. I repeated the above and the same thing happened. What could be going wrong here? Do I just need to keep repeating this process more and more? The car is a 1990 325i 5-speed.

[pwagon717]

I have the same problem, and I flushed mine about twice already.

[M20power93]

how's yours run?

[jlevie]

If you have had a head gasket failure that resulted in oil getting into the coolant you need to do a more effective flush after repairing the head/gasket. That means:

1) Get the front of the car 1-2' in the air on jack-stands.

2) Drain the coolant, remove the thermostat, and set the heater controls for
full hot. O-ring sealed thermostats require you to make up a temporary
gasket, which can be made out of pasteboard.

3) Add flush compound and fill with plain water. Then run the engine at normal
temperature as specified by the flush manufacturer (usually about 15
minutes at operating temperature). In cooler weather it may be necessary to
block off some of the air into the radiator to decrease the warmup time.

4) Allow the engine to cool until you can place your hand on the cylinder head
w/o discomfort. Drain the system and refill with plain water.

5) Run the engine for 10-15 minutes or until temp is close to normal.

6) Repeat (4) and (5) until the water drained from the system is clear and
free of debris.

7) Fill with coolant. It is best to dilute anitfreeze with distilled water.
Tap water contains disolved oxygen and may contain minerals. Either of
which will reduce the lifetime of the coolant.

Notes:

You don't absolutely need to remove the thermostat, but doing so will allow
continuous flow through the radiator and will also make draining & filling
faster and easier.

Always allow the engine to cool to the point that you can hold your hand on
the cylinder head without discomfort. That will prevent scalds from hot
coolant and prevent thermally shocking the head when you dump the coolant.

Filling the system with hot water makes the process go faster and keeps from
having to run the engine a lot in a cold condition (rich mixture).

[M20power93]

is it alright to use 50/50 in the above steps?

[Van Westervelt]

Yes, just slighty pointless and you shouldnt be washing that down the driveway. Also, coolant costs more than water when you are just cycling, so its rather pointless.

Also, if you are using a flush mixture, you shouldnt be using any coolant with that. And typically, they want you to cycle water through the system a few times to be sure the flush cleansers are all the way out.