Illinois | mschultz - 8/1/2018 01:50
The cylinder liner issue has to do with an incorrect assembly specification. If the 9.0 were rated at only 200HP in the 9770, the cylinder liner height would still be incorrect in certain serial number motors.
-Mike
Concerning the cylinder liner issue; The JD service manager explained the problem to me while sitting in his office while our 9770 was receiving a new $25,000 reman engine. I made a comment that the 9 liter must be a problematic engine, his reply was that the 9 liter is a very good engine in lower hp applications. He went on to explain the different tractor models that the 9 liter is used in and that they have had very few problems in those applications. The problem he continued, is when Deere took the engine to design limits that they began having head gasket failures. The problem is the stress applied to the head gasket due to high internal cylinder pressure and temperatures. Anytime your making 400 hp with the same engine block and cubic inches as one producing 200 hp there is going to be a lot more pressure and heat within the cylinder chamber forcing that piston downward. Lower hp applications the cylinder head gasket isn't subjected to the extreme conditions and has shown to hold up under the initial cylinder liner specs. Anytime you run an engine at 100 percent its limit vs operating one at 50 percent the one at 100 percent will typically fail sooner. Its been awhile but it seems that the initial cylinder liner spec. was .005 above the block, and the new spec is .009 above the block plus they made an improvement to the head gasket.
Edited by illinifarmer1 8/1/2018 20:24
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9770 combine vs case combine of the same color lets start a color war
