316ti - Gunk in coolant filler cap

Took a punt on a cheap (too cheap) red 2002 316ti last week. Drove fine, really well actually. Tiny wheels but have a spare set of MV2s to put on, would make a nice little run around for the Mrs.

Engine-wise, 1.8 M42B18 I think. No gunk under oil filler cap, no gunk on dipstick. Rookie error, never checked in the coolant. Got home, coolant light. Opened rad cap to find lots of creamy gunk. Strangely enough, plenty of water in engine.

Car has sat for a time, has an indicated 86k miles (no history tho) Didn't overheat, drove it 20 miles home with no issue other than the heater not getting warm. Planning to flush the rad over the weekend and hope for the best. Grasping at straws, I fear a HG.

Any advice/tips?

If it's sat for a while it may be condensation after building up. I agree flush the rad. Fresh petrol and a service and drive on until it shows signs of an issue. Other than that get a compression test done.

That's my plan alright. Wondering where would the gunge have come from in the first place? Condensation in the oil fair enough but oil in the coolant?

Depending on the volume it would be from sitting up. I've seen cars have it even when been driven due to short spins only. I've also seen cars do a headgasket showing no mixing / sludge. How is it driving and have you checked the header pipes for temp and hardness?

Fingers firmly crossed on this one so. It really drives fine, no flat spots, temp needle plumb centre. Doesn't have that boiled smell that's tell tale of being boiled previously.

Haven't done a thing with it yet, haven't even washed it! Will get under the bonnet to flush and bleed over the next few days and report back.

Is there warm air coming out the vents when the internal heat is up full and the engine is warm?
If not your HG is prob gone

No warm air, however I'm clinging to the hope it is air locked.

HC? Do you mean HG?

Quote:

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Originally Posted by Roberto

No warm air, however I'm clinging to the hope it is air locked.

HC? Do you mean HG?

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I do, damned predictive text...
changed now

If there was oil mixing with coolant it should go both ways, ie you would have Mayo in you oil.
[hr]
Could it be Radweld or something similar in the coolant?

Couldn't be oil cooler leak not sure on that engine. .want to make sure waters circulating but id suspect gasket. .not end of the world

Will know more ince I've flushed engine and got it up to temp. Meantime, had a quick poke around last night, engine protector stopped me draining it. Coolant filler and oil filler pics below:

Attachment 5117
Attachment 5118

Slightly worried about the cable tie:

Attachment 5119

Looks to me like hg is gone

Given that the oil cap is free from mayonnaise the headgasket's integrity seems fine. It almost looks like someone put oil in the expansion bottle mistakenly at some point? If the HG was gone, you'd have the same build up under that and you'd notice the exhaust smoke had a white tinge to it.

Flush the cooling system thoroughly, and fill it up with new coolant/water mix. Run it for a day, and then check.

Is that an oil to water heat exchanger with the cable tie on it?
If so I'd put money on that being the culprit.

Quote:

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Originally Posted by John_D

Is that an oil to water heat exchanger with the cable tie on it?
If so I'd put money on that being the culprit.

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I've no idea what that part is or does...! Open to suggestions.

Flushed the rad, painfully slow with the gunk. Not 100& clean. Water not flowing freely thru the system. Below is the gunk that came out of it.

On a coffee break :D

Attachment 5121

Got things flowing well again, all levels correct, system bled. Unreal amount of gunk! Still none in the engine proper which is good news. Will investigate the heat exchanger next, still no hot air from the vents.

I think this may be the culprit: Oil heat exchanger. Granted not AT as per link.
https://answers.yahoo.com/question/index?qid=20110830114152AA7FyM9

Feasible DIY?

If you look at this link on realoem, there's a cooling line for the Auto box, but not for the manual. This is unlikely to be your issue.

http://www.realoem.com/bmw/enUS/partgrp?id=AT52-EUR-07-2002-E46-BMW-316ti&mg=17