those guys in montreal are good.they did a 87 vw td head for me quite a few years ago.it was severely cracked at the injector port and between several of the valves.this head was a special alloy.the engine was a total overhaul and gave me reliable service for quite a few years before being sold.i wish i could remember the name

I have to cut it up anyway to get it into the forge, so I will be sure to have my digital camera handy when I do.

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Keep everything as simple as possible-but no simpler--Albert Einstein

I don't disagree with anything here, the problem is it may have been overheated at some point in its past. I learned that my head was momentarily overheated at 55k. I just replaced it at 129k. The head was off to replace a blown head gasket between #1 and the chain case (2nd failure in 60k mi) and had hairline cracks at the #4 and #5 cylinders. I'm sure the head would have still functioned, but it would only be a matter of time, and I didn't want to have to worry about it.

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Chris

'04 ML500 - 53k, Inspiration Edition, Desert Silver
'11 Audi A4 Avant - Brilliant Black
'87 300SDL sold
'99 C280 Sport sold
'85 190E 2.3 sold

My #14 head just passed the health exam. It held perfectly constant pressure for half an hour from my newly acquired cooling system pressure tester. I hear people mentioning the "cold hard hose" test a lot but I think this is by far the most reliable test. I also had the valve cover off recently and didn't see any cracks.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL

Having the valve cover off wouldn't allow you to see any cracks unless it is tremendously catastrophic. The cracks are on the combustion chamber side. I am not real sure about the pressure test as a check, either. Mine would hold pressure in the system for days, that is why the upper radiator hose is hard when cold, it is holding pressure. I think the truly best test is checking for combustion gases in the cooling system, but the circumstantial evidence is usually enough to prove the problem.

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Keep everything as simple as possible-but no simpler--Albert Einstein

I just went through the cooling system in June and every part I took off looked original. So I am going to say hopefully mine has never been overheated.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I bought a pristine '87 300D almost exactly one year ago, it had all service records and was clean as a whistle but it had some messy oil leaks, fuel leaks and so on. It needed some steering bushings and shocks but had a recent trans rebuild
$2300 for the car and over $3.5K into restoration and I am very happy. Right after buying the car I had the head removed by a Indy that loves these engines. He knows them like the back of his hand. The head was sent to be pressure checked, new valve guides and a skim cut to ensure flatness, it was very flat to begin with but the rebuilder wanted to remove a small area of corrosion where the head gasket had started weeping oil. If the corrosion was severe like I have seen on some 300E gassers, I'd have gone with a new head. Maintenance obviously pays off here.

I somewhat reluctantly gave the OK to reuse the head, I would have liked to find a newer one but I really didn't want to dig deeper in my pockets at that time. I figured since the head made it to 250K miles, with the same care it would last me another 100K.
New: front seal, lifters, water pump, radiator, seals on the IP. Results are no leaks and wow! strong! This is the best diesel I've ever driven. Damn I like to crank it open and mess with ricers - had it up to 105 where it still felt like it wanted to GO! I don't pray to the #14 Gods, I just keep an eye on the temp gauge and plan on keeping up up the regular maintenance I normally use with the "fleet".
1971 220 (gas) 4-spd manual 106441
1979 300TD w/ ’85 turbo engine 295530
1983 300D 243280
1985 300TD 217300
1987 300D 262300

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'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!

I thought the upper radiator hose was supposed to be squishy when cold??? I thought hard was the bad sign. Am I dyslexic, or just confused, or both?

It is supposed to be squishy, hard is a bad thing. I guess I wasn't as clear as I could have been. What I meant was that since the hose was hard, that shows the system is holding pressure. If the system wasn't holding pressure, the hose would be soft. Therefore simply checking to see if the system holds pressure isn't a valid test of the condition of the head. My head was most definitely cracked, but yet the system held pressure for days-evidence for which was provided by the hard (when cold) radiator hose (seemingly one of the surest signs of a cracked head).

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Keep everything as simple as possible-but no simpler--Albert Einstein

I think the pressure test is valid because if your head is bad you have a hole between the combustion chamber and the cooling system, hence the cold hard hose. But if you release the pressure by removing the cap and installing the pressure tester you are building pressure from the cooling system side, not the combustion side, and if the head is bad the cooling system won't hold constant pressure.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL

The upper radiator hose on my 300D is actually slightly collapsed when cold. If you open the coolant bottle, you can hear it pull vacuum. I've definitely felt the radiator hose on a car with head cracks and it was ROCK HARD. You could tell the hose was almost ready to snap off the radiator neck. Not a good thing.... Also, the temp guage on this car would routinely reach the 120 C mark... Glad it wasn't my car...

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1960 MB 190Db w/ full sunroof
1985 Toyota Pickup
2006 Honda Odyssey EXL R&N
2001 VW Jetta GLS TDI

DA, I wish it were that easy - but it's not. The nature of the head cracks is such that the 20psi you test with isn't sufficient to show the leak. Combustion pressures, in thousands of PSI, are able to escape through the hairline crack and cause abnormal pressure in the cooling system but only under load (in the early stages of the crack). When it gets severe, you will see bubbles in the coolant tank, and probably hydrolock shortly thereafter. Anyway, point being, the pressure testers cannot diagnose this problem. The cold hard hose test is about the only way I know to check, and that only works if the system passes the ~20psi test and is NOT losing coolant. Guess I need to add this to the FAQ's.

Well the owner's manual for this tester also says that to check for combustion leaks you can attach the tester while idling the engine and look for fluctuations of the pressure needle. I haven't tried this yet and it's probably not gonna work on a diesel engine because of the vibration, but I'll probably try anyway. I know what you're saying about the cracks not showing leakage at 20 psi. It would have to be a massive crack to show leakage at such a low pressure at which point I'd probably have other symptoms too. I still find this tester very useful though, because it has helped me locate loose hose clamps and a seeping radiator on my 240D.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL

The cracks aren't visible from outside, they form between the valves or between valves and prechamber. When they penetrate the coolant passages, combusion gasses will collect in the cooling system, causing the "hard hose cold" problem. Eventually, coolant will travel into the combustion chamber, causing even more trouble.

Unless you are loosing coolant, the pressure tester won't show significant leakdown. If it does, remove the injectors and hand crank the engine around until you clear the coolant out of it, or you will probably bend a rod when you try to start it from the coolant in the leaking combustion chamber.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

The problem is, you can't monitor the gauge while driving, and at idle there's not enough pressure to show any fluctuations. On my white car, I could releae pressure in the system, and drive around for an hour with a light foot, and have a soft hose at operating temp. But if I do *one* full throttle run to 60mph, bam, instant high pressure in the system, despite *no* change in operating temp (maybe go from 85C to 90C on the dash gauge). Only when the crack gets severe will anything be detectable at idle, or with the combustion gasses test kits, etc. If you have a #14 head and plan to keep your car forever (like me), it's a good idea to keep an eye out for a good deal on a used #17 head to put on the shelf for later on.