Driving back from picking up my sailboat today, the temp gauge started climbing. It's never hit 210 before. Got to to 220, then dropped down and then swung up and down. Low coolant light came on. Stopped and looked at coolant reservoir. It was empty. It was at a normal level about 2 or 3 weeks ago when I checked it. Put in about a gallon and half of coolant and released some pressure on the cap so it would suck it back in. Temperatures went back to normal for rest of drive home. There's been no evidence of any coolant leaks and top hose was not hard. But I just pulled the dipstick. I did an oil change less than 100 miles ago. I'm attaching pictures. There are water droplets high on the stic, there's sludge on the stick above the check indicators, level reads high and there are little bubbles in the oil at the bottom of the stick. Never any sludge or droplets on the dipstick in the past. I think it's done for.

Attached Thumbnails

       

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Yikes. What do you think happened? HG?

Do you think the coolant flushed out all the sludge out of the motor and deposited it on the stick or that the sludge has been building up there for a while?

Are you gonna replace the engine or the truck?

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."

I think it's an internal crack in the block. No white smoke so I don't think coolant is getting in the combustion chambers. Oil was changed last week. Never ever any indication of sludge on the dipstick in the past. I think the sludge was formed from the oil/coolant combo. Also, I forgot to mention that after I got home, I removed the oil fill cap to check underneath to see if there was sludge. When I did a whisp of white 'smoke' came out of the oil fill hole. I thought immediately, I hope that's smoke and not steam. I think it was steam.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Pressure test it, or trade it in while it still runs.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Crazy question, but does the truck have an oil-cooler built into the radiator, or an oil-to-water cooler? There are multiple ways coolant can mix with oil, and all aren't necessarily fatal to a motor.

It's got a separate oil cooler. I'm open to any suggestion as to how the oil and coolant became far too familiar with each other. It happened quickly I think. I anticipate that in the morning I'll be able to see the separation between the oil and coolant on the stick. Stick is reading about a gallon high at the moment and it's very thin.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Hmmmm? The pressure test comment does point to a diverging data point. Radiator had a lot of pressure in it when I added the coolant and turned the cap to the first stop to release the pressure and get the coolant to flow into the radiator from the reservoir. Seems like a cracked block wouldn't have allowed that pressure to be sustained.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Hat is correct. The first step is to pressure test it. A tester kit costs somewhere between fifty and a hundred bucks. I can't remember what I paid for mine. If you don't want to buy a pressure tester, a radiator shop will pressure it up for little or nothing.

Don't give up on it before diagnosis. Don't guess.

I read your last post. You can't get coolant into the radiator from the reservoir without the engine cooling and drawing it in. You need to let it completely cool off and then fill the radiator.

Wait a minute. What are you calling a reservoir? Are you actually talking about the overflow tank, or a pressure tank that serves the purpose of the top radiator tank?

Due to some of the labels on many vehicles, lots of folks believe that you should never remove the radiator cap no matter what. You should remove the radiator cap when it's dead cold and see to the level that way.

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

I'm not guessing about a couple of things. Coolant level went down. Crankcase level went up. Changed the oil a week ago and checked it twice since then. Not much doubt about that. It was just a hair over full. Not it's a good inch or more over full and oil is thin and runny, not like the way Rotella Synthetic usually behaves--it kinda sticks to surfaces. Not much doubt about loss of coolant. Was planning a 4k trip next week so checked coolant reservoir last week also. It was just right. It was dry today.

These engines are known for cracking heads, blowing headgaskets and cracking blocks. I doubt that much coolant could have gone thru the combustion chambers without producing a lot of white smoke. No white smoke. Perhaps there is a way of coolant getting into the oil without cracking the block.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Yeah, that's a profuse transfer of fluids. There are a few things I might try such as watching the coolant for bubbles while leak-down testing each cylinder, but it would probably be academic at this point.. It sounds like it might be time for exploratory surgery.

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

It's a small enough leak to use liquid glass on. Very high chance of long term success on something like this.

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1985 500SL Euro w/ AMG bits 130k
1984 300SD Turbodiesel 192k
1980 240D Stick China 188k
2001 CLK55 AMG 101k
2007 S600 Biturbo 149k Overheated Project, IT'S ALIVE!!!

good old mechanic in a bottle. goodbye radiator!

dont you sell cars for a living?

that makes it even scarier.

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have no worries.....President Obama swears "If you like your gun, you can keep it

Junk Motors' legacy with diesel engines began with the 1978 Oldsmobile 88s and 98s.

Maybe they are going back to their roots.

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)

hope for the best, prepare for the worst.

assuming its internally cracked seems to me a bit premature. the pressure test might show something, a leakdown test might show more.

ive got my finger crossed for a head gasket, which aint too bad a job on the 6.5.

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How many times have you done it? Long term results?

I've never retailed a car after I've done this. Dumped them at auction, yes.

If you spent more than a few months in the business you would understand, or go broke. A lot of pass the turd going on at auctions.

...and I doubt I'll be doing it "for a living" much longer.

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1985 500SL Euro w/ AMG bits 130k
1984 300SD Turbodiesel 192k
1980 240D Stick China 188k
2001 CLK55 AMG 101k
2007 S600 Biturbo 149k Overheated Project, IT'S ALIVE!!!