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Old 07-13-2021, 02:56 PM
oldskewel oldskewel is offline
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Quote:
Originally Posted by Effduration View Post
I am sorry to hear all this...This is pretty unusual.

Coolant left over in the exhaust from previous overheat could be causing smoke. I would confirm you are getting coolant in cylinders by swabbing cylinders one morning after running the day before.

Oil leaking from head gasket at front right (passenger side) corner? That is pretty unusual. First off the oil is not under pressure in that area...that area has gravity oil drains to bring oil back to the pan. There are only the M8 skinny bolts in the corners...but they are of different lengths (left and right) did you use the right one? Any chance it stripped?

And you did the proper head bolt torque? 30 ft-lbs then a 90 degree and another 90 degree in proper order?
I agree with all this, especially the "sorry to hear this" part

To add a couple of ideas:

On the oil leak - could it be coming from the valve cover (cylinder head cover)? I think I might have had an initial minor leak, that was easily fixed, left some residual oil that made a little smoke. No big deal, but was a little concerning.

EDIT - now I see yours is on the driver's side. There are a lot of other things that could be leaking oil in that area. VANOS, valve cover, oil filter housing.

The coolant is probably the main thing I'd target right now. I think the theory is that you have some sort of seal failure between cooling and combustion - maybe HG, maybe crack, maybe head bolt torquing issue.

Your symptoms are (I'm filling in here): losing coolant, no overflow at the expansion tank (that would happen if exceeding 2 bar), radiator hose suctioned flat the next day, possible water vapor in the exhaust. The fact that you're NOT overflowing at the expansion tank is good, maybe indicating a less serious issue.

If that is true, then @Effduration's suggestion to "swab" the cylinders would be a good, direct test. Remove spark plugs, and poke a paper towel on a stick or something through there, and see if you get any coolant on it. In the testing I did before my HG work, to confirm my HG leakage issue (warped head, in my case), I actually pressurized the cooling system with the engine cold, waited a couple of hours and did that swab test to easily confirm coolant in the cylinders.

BTW, the reason the hoses are sucked flat is that the air that was in there to begin with (air gap at the top of the expansion tank) somehow mixed with water vapor and leaked out during driving when the coolant was hot and pressurized. Then once it cooled down, the water vapor condensed back to water, but the air has gone, so you've got a pretty good vacuum, sucking the hoses flat.

But your leak could be somewhere else. I had a minor but annoying leak due to low quality o-rings on the new water pipes that go into the head. The leak is buried so deep (under the intake manifold, behind the oil filter housing, etc.) that it may be hard to see. But the coolant will vanish, and some level of cool-down suction will result, even without a serious problem.
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