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DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

So before I ran my 931 for the first time, the oil was clean, the coolant was clean, and after running it a few times they oil is now a white/milky color. I think I've got a blown head gasket. So I'm going to begin tearing into the engine to get at the gasket, does anyone have a preferred manual or write-up they would recommend for me to go by, something with torque specs and such.

Also any recommendations on what to hit up on my way in there other than vacuum (done it) and water pump (will do it)

I'm really in need of torque specs though, most of the stuff is straight forward.
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1979 924 (Daily driver EFI)
1979 924 Sebring
1977 924
1977 924 (Parts)

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

A car that sat for a long time, and was only briefly fired will produce condensation in the crankcase. You sure it's coolant?
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WeiBe (1987 924S 2.5t) - 931 S3

DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

It seems like a lot, If it's not I've already torn half the engine out for a head gasket, gonna pull the head tomorrow.

At first i knew the oil was overfull form the last guy and thought that maybe it was just airated from the crank splashing into it, but I checked in the filler cap and it was a very white and light brown mix. Maybe it was just condensation; honestly I hope it was. Like I said though, I'm far enough into it that I may as well replace the head gasket in case it really is the culprit.

Sorry for no pictures. I pretty much just started digging into it all, might post some tomorrow though.
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1979 924 (Daily driver EFI)
1979 924 Sebring
1977 924
1977 924 (Parts)

DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

Hey Rasta, you just could be right about the condensation, but how much condensation should one really expect? So today I drained the oil, looks like a consistent light brown/milky color. Then I drained the coolant, and it was clean and new. Is that a possibility with a head gasket failure for one fluid to mix into the other and not vice versa?

Not only that, but I took off the oil cooler lines and literally the first thing that came pouring out was clear water. I smelled it and confirmed it to be water and not fuel. After letting it run out it soon turned to the same light milky color. Then after I pulled both lines and removed the cooler, I tipped the cooler and lines to drain out and it got a really dark chunky consistency.

All that being said I'm beginning to think it may not be the head gasket, but I would really hate to have come this far, put it together, and then have that be the issue. So im going to replace it anyways, I've just never heard of condensation building up inside engines like this. I guess you learn something new everyday.

Pics later tonight
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1979 924 (Daily driver EFI)
1979 924 Sebring
1977 924
1977 924 (Parts)

DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

Intake off

Filler cap

Oil draining

Water that poured out of the oil cooler line

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1979 924 (Daily driver EFI)
1979 924 Sebring
1977 924
1977 924 (Parts)

emoore924 · Joined: 13 Apr 2004 Posts: 2822

Oh my. No, I don't think that's just condensation.

If you have a failure between the oil and water, you generally mix oil in the water and water in the oil, but not always. Sometimes is just goes one way.

What happens is each of the systems is pressurized when the car is running -- the water at about 13 psi and the oil up to about 50 (depending on where the breach is). The car can mix fluids when it is running. Or once that pressure ends, like when the car cools down, the oil can get sucked into the water as the water system depressurizes, or water squirts into the oil as the oil pressure goes to zero but the cooling system is still at 13, 12, 11...). Do that through a couple of cold-hot-cold cycles and you end up with the mess you see.

It is most likely a head gasket. That is a known failure point on these engines. BUT it could be a cracked block or cracked head. You can do diags like looking for exhaust in the cooling system, pressurizing the coolant and seeing whether the level drops, by how much and where is it going... But either way, you're going to have to take the head off and see what's going on -- no small task on a turbo. And you need to clean all that crud out of the oil/water passages before you ruin the rod and main bearings and the rest of the oil-lubricated surfaces like cam, followers...

I'm guessing your coolant level was dropping and your oil level was going up?

Good luck with this one!

DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

All I have to do at this point is take out the head bolts and I'll take it off. I managed to weasel my tools and fingers into the tight spots and got the manifold to turbo and wastegate bolts off, so I'll take the manifold with the head tomorrow. It's supposed to warm up the rest of the week and today was miserable. Felt like touching my tools would give me frost bite

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1979 924 (Daily driver EFI)
1979 924 Sebring
1977 924
1977 924 (Parts)

DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

Head is pulled and the gasket was just fine, but I have a different suspicion as to what the water was from. When I first got the car, there was and still is evidence of a fire in the engine bay. The PO got the car to run with a 5 gallon bucket of fuel (didn't bother to retrieve his quick connects from the fuel lines before selling it) and managed to start a fire that melted a lot of the sound deadening glued to the hood. I'm pretty sure once he started this fire he sprayed all kinds of water into the intake and all over. Given that I even poured a little water from one of the wire harnesses, I think it's safe to say he sprayed it just about everywhere. Cylinder 3's intake runner had a lot of corrosion and looked to be the cylinder the water drained down to.

I imagine something like this would have happened:

https://www.youtube.com/watch?v=2RBRCaVjYrM

I'm replacing the head gasket anyways and cleaning the head and everything up really well while im at it. Any suggestions on how to flush the oil/water shit from my block and head though?
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1979 924 (Daily driver EFI)
1979 924 Sebring
1977 924
1977 924 (Parts)

emoore924 · Joined: 13 Apr 2004 Posts: 2822

Not to question you but how did you come to the conclusion that the HG was fine? Do you have some pics you could post so we could check it out?

Could be the fire thing is what happened but I'd want to be pretty sure that's the case before I buttoned it all up again. Sounds more like a flood car to me. Where did you buy it or where did it live before you got it?

See if your local machinist will pressure test the head for you. At least that would rule out a crack there.

Call the PO and see if you can corroborate your suspicions regarding the combustion history of the car. (The underhood foam has often failed/gone in these cars all by itself).

If he/she confirms your suspicions, I might consider their spraying down the engine compartment as a potential source of the moisture. But I find that kind of hard to believe given that the water is in just about everything.

MikeDanger · Joined: 21 Nov 2002 Posts: 774 Location: Denver

Man, sucks to be you, maybe its karma....
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DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

I'll post some pictures a little later today of the head gasket and stuff for you to look at, but im confident it's not the cause.

The car was found in Wyoming, and although it did have a little interior water damage due to the window being down, I don't think it's a flood car.

There was definitely a fire because a lot of the wires and wire harness is melted, which I've had to replace a ton and still have a lot to replace. Also there were some larger plastic components that I removed that were clearly on fire at one point. The fire looks to have been in a few different locations, there's no one definite location as to where it started. That's why it seems like the guy was just irresponsible with the fuel he had.

Something else I'd like to note though, My coolant was perfectly clean, and only the oil was contaminated. The guy had the factory airbox in the hatchback because It's all messed up. That being said, If he had a fire with the airbox disconnected and decided to spray water in there, the air oil separator was wide open, and any water in that would have drained straight down into the oil pan. Or even if it just sat through the elements that would be water's way of getting in. There were no bubbles in the coolant when I ran it, and the coolant was clean. So considering the oil is a higher pressure than the coolant I would think if it were a head gasket problem that the oil would go into the coolant as well.

Unless coolant turns to pure water once mixed with oil, which I'm sure it doesn't, then It's definitely just water and not coolant, and I'll need to just flush the system really well.
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1979 924 (Daily driver EFI)
1979 924 Sebring
1977 924
1977 924 (Parts)

DZGunner · Joined: 18 Nov 2014 Posts: 191 Location: Great white north

This is the back

The block

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1979 924 (Daily driver EFI)
1979 924 Sebring
1977 924
1977 924 (Parts)

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Hard to tell from those pix, but looks like possible failure of the fire ring on #4.
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emoore924 · Joined: 13 Apr 2004 Posts: 2822

Yep, the pics aren't great and hard to tell without holding it in your hands...

Agreed that #4 fire ring not happy. Also it looks like there could be oil/water breach between the Darlington raceway head/block oil passage seal at the edge between 2/3 (where the oil always leaks) and the small water passage right next to it.