Have you confirmed that your turbo is operating correctly?

Could the screeching you heard have been the turbo seizing up?

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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

Re-check valve clearances, they may have gotten tight again, causing compression loss when car gets hot.

Unlikely, but maybe you have a clogged fuel vent?
Try removing the fuel cap the next time it dies when hot.

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78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

I haven't put a boost gauge on it yet, but it spins freely by hand and there isn't a ton of end play.

Clogged fuel strainer in tank. Time running rather than heat could be the factor. As it sucks fuel through strainer in the tank, gunk builds up until it can't get fuel and stalls. Then it sits a while, gunk settles down, starts up runs fine. Then builds up again and dies after 10 minutes. Coincidentally its the same amount of time it takes the car to warm up. It's possible . I've towed a couple cause of this stupid issue.

Easiest thing to do is unplug the rubber line under the hood from the metal supply line coming from the tank. Put a 3/8 or 5/16 hose coupler in the rubber line and some rubber hose to a gas can. Put the return rubber line (cigar hose ) into gas can too with an extension if needed. Pump the primer a bit and start it up, let it idle a bit til it gets warm revving it and keep gas in your new tank. See what happens.

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What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius

Tank strainer is perfectly clear. I checked it when I drained the tank to make sure I had quality fuel.

Well it started up almost instantly today, after refusing to re-start last night after it died. It was acting exactly like the battery was dead last night but cranked and fired today no problem.

I checked the fuel tank vent and it seemed ok. I took it off completely just to be sure. Just like before, it idled nicely and had low power, but could at least cruise very slowly around the block. However, once it gets up to temperature, it looses the small amount of power it has and just creeps along (~5mph max), then starts running really rough, slows down to a stop, and dies. When trying to restart, it very slowly cranks and won't start, just like a dead battery situation.

I have not measured the turbo boost, as suggested, but I feel like I have bigger problems considering it won't even stay running after it gets hot.

I'm out of ideas, I've tried everything people have suggested. Any idea on what would cause it to act like it has a dead battery once it gets warmed up? I do not think it is overheating, the temp gauge only gets up to 90C. Thanks.

Next time when cold, hookup an external fuel tank (at the primary fuel filter) with enough capacity to run the car until it gets hot.
Have the fuel return go into your external fuel tank.

If it still dies with an external tank when hot, you've ruled out any problems with items aft of the primary fuel filter.

If it doesn't die with an external tank when hot, you know your problem is aft of the primary fuel filter.

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78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

Thank You. A few people have suggested this, and I'll give it a try once I get it restarted (I'm assuming it will restart once it cools down), but I don't understand how this could be related to it acting like the battery is dead once it gets hot. I can understand that this might be causing my probably fuel starvation issue, but don't see why it would prevent the starter from cranking properly.

Have you put a socket on the crank bolt and tried to turn it over manually when it acts like the battery is dead to see if the engine is getting tight? Or at least tried to turn it with a crescent wrench on the PS pulley bolt?

__________________
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

Just tried this. It is turning the same way it always does.

I changed the inline fuel filter yesterday even though it didn't look bad. I just took a look at the new inline fuel filter and noticed some black and orange particles floating around. I pulled it off and cut it open and it had a little ball of sludge in the screened area about the size of a small pea.

I'd like to think this is the cause of my issues, but the filter was brand new yesterday and it did not run any different when it was brand new.

Just a WAG, but do you have oil on the air filter element, or a pool of oil in the air filter housing?
Any modifications to the stock crankcase vapor recovery system?

My best guess is that there is a blockage of the crankcase oil return line.
As a result, rising crankcase pressure will push on the diaphragm of the shutoff valve and cause the car to shut off.
(Just like applying vacuum to the other side of the diaphragm during the normal shutdown with the key).
This will cause loss of power and eventual shut down of the engine (or oil leaks all over the place in severe cases).
This will occur even with the vacuum hose to the shutoff valve being disconnected.

1) Try the external fuel tank with the engine cold and the crankcase breather hose disconnected.
If the engine does shut down when it gets hot, with and external tank connected and the crankcase breather disconnected, then you know it something forward of the primary fuel filter is to blame
(and it's not a blockage of the crankcase oil return line).

2) If the engine does not shut down when hot, with the external tank connected and the crankcase breather disconnected,
you know it could be something aft of the primary fuel filter or that there is a blockage of the crankcase oil return line.

3) If the engine still runs when hot, reconnect the crankcase breather hose to the valvecover.
If the engine now shuts down, you know there is a problem with the crankcase oil return.
If the engine now doesn't shut down, you know the case is aft of the primary fuel filter.

If excessive crankcase pressure is causing the engine to shut off: another way to test would be...attach a pressure gauge (MityVac set on pressure) to the shutoff valve when the engine is cold,
and check see if it the pressure increases as the car shuts off when hot.
I suspect the amount of pressure to activate the shutoff valve (backwards of it's intended fashion) would register on the MityVac gauge.

This was the only thing I could think of that would completely explain your symptoms, including the inability to restart the car.
If it's not a blocked oil recovery line at the root cause of your symptoms, then I'm stumped for now.

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78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

If the engine will not turn over well when hot and restart. Some wd 40 sprayed down the intake throat with the air breather cover off might be worth trying.


There is a chance if it will not light off this way the engine is partially bound up. You mentioned a squeeling noise at one point in your descriptions that was not identified.


Part of your description looks like it may be binding up a little more as it warms up. With the glow plugs out the engine should turn fairly freely.


This post is just an item that cannot totally be overlooked unfortunately. Not a certainty it is the problem.


Hot it would not crank well but more like a very weak battery. Yet cold the next morning it would crank normally. This is not normal. Also this clang noise you hear might be related to a bearing failure or something else mechanical.


As an example if you ever get a clang on engine shutdown. More times than not you have a broken crank. These engines fortunately have a robust crankshaft and seldom break. At the same time bearing issues are known.

A quick look at your post history shows you had problems with the alternator, water pump, crank pulley, vacuum pump and probably more. You had screeching or squealing noise from the engine since you acquired the car., then you discovered a red rag inside the valve cover..... that is a big red flag IMO. You said there is no air in fuel per the clear return to tank line- that is good.

Can you post a video of the engine idling, reving and the squeal/ screech? Have you tried to isolate where the squeal/screech is coming from? Is it internal or external (alternator, water pump, AC compressor belt/ bearing) to the engine? Use a wooden broom stick cut to length as a stethoscope and see if you can localize where the squeal is coming from.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Could it be a bearing that is expanding when it warms up and seizing the engine?