2012 RTV400 CI no compression

[quawk]

New to this forum and to Kubota ownership. Have joined looking for help and advice on a newly acquired Kubota RTV400 ci. Was purchased at a consignment aucion in non running condition. I knew and was able to discuss with the consigner about the machine. Had quit on him while doing chores on his farm. Would not restart. He took it to a local dealer and was told it had no compression and it would be $1900 to repair it, so he took it to the consignment auction. Fast forward to it coming in to my shop. Removed the valve cover to discover the pin/shaft that the cam rides on had backed out of the side of the case, the cam then had fallen out of place, and cam chain derailed so, of course no valve movement, thus no compression. I do realize this machine has a Subaru engine and have found the production no. ex420ds70009215 and the serial no. 0003421. Am looking for a parts diagram. Have looked at one on the Messicks website but am trying to determine the small crescent shaped part and odd shaped spring that fits onto the side of the cam sprocket according to the parts diagram. These parts do not seem to be present. Wondering if they could have dropped down the cavity that the cam chain travels in. Would appreciate any help with finding a parts diagram or service manual explaining the operation of these small parts that look like they belong on the cam sprocket. Are these something that operate as a decompression system? Have found a parts diagram for the EX400DS series engines, but not the EX420DS series engines. Any help or advice would be appreciated.

 

[North Idaho Wolfman]

Need the unit serial number not the engine serial number.

 

[quawk]

Need the unit serial number not the engine serial number.

By unit serial number, do you mean the serial number of the side x side itself? Was hoping to find a parts diagram or manual for the engine itself, as this issue really has nothing to do with the rest of the machine. I might add, what does the ci in the machine name stand for, and what does the A/H suffix in the name refer to when looking for a parts diagram?

 

[quawk]

Upon further looking at the parts diagram provided on the Messicks website, for this machine, in the engine section, the page 160000 view shows the cam without the afore mentioned parts that I'm wondering about whether or not they are missing. If you scroll down to the bottom of the engine diagrams, to page 192000, it shows what is titled as camshaft kit(option). This is where this additional crescent shaped part and a return spring and a clip are shown and listed. Since this is listed as an option, I assume that this did not come on all of the machines of that model name. But, what did these additional parts do? Did they, as I asked before, provide a decompression feature, and if so why was it optional? I would think that if they were deemed necessary, they would have been on all of those engines. Guess what I want to know is can anyone verify if any of these engines are built without the automatic decompression system? Was the decompression feature used primarily on the pull start engines to make starting easier, and possibly deemed unnecessary on the electric start machines? Any response or info would be appreciated.

 

[North Idaho Wolfman]

The side by sides serial number will tell which motor came in it and point to the proper engine blueprints.
There are possibly mutiple variations in the build of that SxS.

 

[Russell King]

@quawk

Since you mentioned in another thread that you resolved your issue would you please post what the problem resolution was on the engine problem?