400 case question

Rexkramer

Member
What are the odds that one of these would crack a head? I'm picking up a diesel 400 and I was told both heads are cracked. motor is half apart right now, I don't see any info online about these motors. Is it worth fixing or are they trouble? Never had a case before! Thanks in advance!!!
 
Case diesel heads are a Lanova cycle pre-chamber design. Due to the complexity of machining to the head to add the pre-chamber, and how the pre-chambers function cracking as pretty common on these kinds of heads, especially if ether was used on them.
 
Depends where the cracks are whether it's a problem or not. The MF85D I had the head had some small cracks, they were not into the water so it caused no trouble. The Olds 5.7 V-8 diesel heads were known to crack through the middle, into both intake and exhaust valve seats, never caused any problems though..
 
The heads can crack if the motor got hot, but used ones aren't too hard to find, and can cost $125-$150 each. They are the same head as the 377 6 cyl head used on the 500 diesel. They should be stamped A6320A on the top of the head.I have extras. The cylinder sleeves are the wet design with O rings and can leak antifreeze into the oil. On the side of the injection pump is a transfer pump that can leak diesel fuel into the oil. Usually a new seal will fix that. If the motor has sat apart very long the injection pump head can stick, and ruin a shaft inside the injection pump when the motor is turned over. If that happens it takes a different pump to fix,(expensive), because they are no longer available. As long as you are careful, you should be able to fix it. They aren't hard to work on,Good luck.
 
The 400 engine was, in my opinion, a very good design with 5 main bearings for a very strong bottom end. The engines also were very fuel efficient and started well in cold weather. The 400 was the all time favorite tractor of old Case dealers. I hope you decide to fix it up. Don
 
I don't know how long it's been apart, long enough that the open cyls are rusty. My thoughts are to pull the other head and get them both checked out. If the other 2 cyls look good I'll re sleeve the rusty ones if the heads check out good. would there be a way to see if the injection pump is loose without pulling it? ive pulled pumps before and its best to line up the marks before you take em off unless this is different than other stuff I've worked on. I'm kinda jumping the gun since I don't have it home yet but I been brainstorming. Thanks guys!
 
I'll echo what others have said. My 400 had both heads cracked. The starter was weak so ether was used to start it. Take the heads to a shop and have them checked for cracks. It does not cost much and then you know what you have. Mine were repairable so I went that route but it was expensive. If it's already partially apart I would go ahead and totally disassemble the engine and overhaul it. Now is the time to replace the sleeve orings if the engine hasn't been overhauled before. If you plan to run it in winter and live where it gets cold put a block heater on it. Mine's plumbed into the water drain and the plug below the heads on the left side of the block. It takes about an hour to warm the engine up and it starts really easy.

Pull the injection pump and have it gone through. It is money well spent. Timing is easy. Set the crank at the desired degree and line up the timing marks on the pump.

You can get copies of the original service manual very easy and it will give you all kinds of information on the engine and the tractor. It is worth the money spent.

One other trick is to replace the original 2 6 volt batteries in series with 2 12 volt batteries in parallel. This requires new battery cables to work. The batteries last much longer and will spin the engine over faster for starting.

Eli
 

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