Why do heads crack on 300 Diesels?

The engine from my 300 TDT is being remanufactured by Metric Motors right now. I talked to Mike at Metric the other day, and found out that the head on my engine was cracked bad around the "prechamber
hole" in 4 out of 5 cylinders, which Mike says is unusually bad cracking.
What causes that to happen?
Thanks.
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No idea... however, I was reading up Bentley's Mercedes Bible from Star Magazine... it told me that MB rebuilds these old diesel motors at their Germany factory... everything is inspected and all... for about the same price as if you were to have Metric do the work... It is fascinating and wondered if they still do this.
You should check.... Call up MBUSA Classic... about this.
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Starting fluid is known to crack the prechambers themselves causing a compression leak. That may have occurred at some time and the current prechambers are in fact replacements - my speculation.
Otherwise, if there needs to be an explanation, I'd suspect overheating the motor but remember, that motor has done a lot of miles - and nothing lasts forever!
I believe you'll be happy with the rebuilt Metric motor.
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Interesting. I just wondered because I don't want to do whatever I did to cause it to happen again. I may have tried using starter fluid a couple of times, but I don't think it ever helped with my engine. Pretty much it either started or it didn't. Long cranking is what got it going when I was visiting Montana or Minnesota combined with putting hot air in the air intake with a hair dryer and using a block heater. My engine had 144,000 miles on it when I got it so I really don't know what they run and start like when new. It will be interesting to find out.
Shipping a motor to Germany and back is not something I would do to reply to Tiger's suggestion about a factory in Germany. One of the best things about Metric besides the helpful, honest guy who runs the shop and it's small size and staff is that it is close enough for me to be able to trailer the motor there and back myself.
I really like Mike, the President of Metric. He was completely comfortable with me coming in his shop and visiting with him. He was working on a block from a 1954 Mercedes when I was there. It was also a 5 cylinder diesel. I don't have my engine back yet, but from what other people who know Metric have told me and my impressions of the shop so far I would recommend the place. I stripped out the heads on the allen socket bolts that hold the vacuum pump in place and a nut was missing on a bracket that holds the exhaust pipe on. I asked Mike if he could recommend a good place to get metric hardware and he just went to his hardware inventory and gave me a handful of the bolts I needed. I decided to replace the front seal on my transimission and Mike got me one of those too for 1/2 what the discount on-line parts places wanted.
I will post on the list when I get the engine back next week.
On Jun 9, 5:09 pm, "-->> T.G. Lambach <<--" <"T.G. Lambach at NoHamorSpamcomcast.net"> wrote:

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The rebuilt engines are ready to go in USA... zero wait time if I am right.
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Ether is supposd to be able to crack the prechambers. I dunno if that really translates into cracking the head - I just don't know. Usually heat as in overheating cracks heads if cold water is suddenly introduced. Has it ever overheated badly?
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