white smoke and an m20

[rede30]

I fired up a 325i that had not ran for about a month and extreme amounts of white smoke came forth. (looked just like seafoam) I never saw anything of the sort before it sat and I did drive it before it sat and it drove fine. I drained the oil and saw no coolant. I did some maintenance like t-belt, cooling system, etc over the last month. Has to be HG right? Nothing else makes sense to me. Probably a slow leak while it sat.

I didn't run it long but it idled fine for about a min and then started to get a bit rough and teh cel came on. Smoke never stopped. The ECU also died while it sat.

[ttrousdell]

coolant somehow getting into the cylinder. thats usually what white smoke means. crack in head or hg might have failed while sitting for so long? I would check the coolant level to see if it starts to go down noticably while running, pressure test.

[87_black_325is]

Head gasket

[rede30]

I got everything back together and I still have smoke, not as much. It doesnt smell like coolant burning at all, just like water vapor. Water droplets that stay on the ground are present when I first start the car. Runs great. I guess I could have done something wrong with the head gasket but I have done it many times and can't see where I would have gone wrong. The head got tested. I was very careful when I torqued the head down.

Would something cause more water vapor as a by product? o2 sensor, AFM?

[Eecen]

How long did you run the car for total?

Moisture will build up in your exhaust system as a car sits.

[rede30]

It has run for maybe 10 min in my barn. I ran it at about 2500 for 5 min and it smoked very little after that but after I fired it up the next day it seemed to be the same. Its like coolant leaks while the car sits. I need to pull plugs and see if coolant sprays out.

[StereoInstaller1]

Pressure test your cooling system, then do a basic compression test.

[jlevie]

It has run for maybe 10 min in my barn. I ran it at about 2500 for 5 min and it smoked very little after that but after I fired it up the next day it seemed to be the same. Its like coolant leaks while the car sits. I need to pull plugs and see if coolant sprays out.

That sounds like a head gasket leak. It may be obvious when you pull the plugs after the the engine has cooled down overnight. Prior to pulling the plugs run the engine long enough for it to get fully up to temperature to pressurize the cooling system.

[rede30]

do you guys think this little divots could cause coolant to leak into my chamber? They are hard to see but they are right on the edge of the surface before the piston.

[jlevie]

Was there supposed to be a picture? "Divots" on the piston have nothing to do with coolant reaching one or more cylinders. That will be a failed head gasket, warped head, cracked head, or rarely a warped block.

[rede30]

Does the picture not show up? I see it. They are small dents on the block surface, not piston

[jlevie]

I couldn't see the picture yesterday, but I can see it now.

Those marks along the edge of the cylinder shouldn't be there, but I doubt they are the cause of the coolant leak. The piston is awfully clean. That and the marks make me suspect that the head has been off the engine before in the recent past. Do you have any history on the car?

Check the head and the block for warp and check the head for cracks.

[rede30]

The block has pretty low miles, really kept up car and the VIN tag on the block matches the car. The head has to have been off before, there was another mark on the head surface that was out of place. The head has been checked out and surfaced.