yamaha diesel

I would like to know if anyone has a manual or info on a yamaha md5y single cylinder diesel. 14 horsepower at 3000 rpm. I have just picked one up and have not seen one before. It looks like a well made engine with a hydraulic gearbox. There is no spelling mistake it is definitely a yamaha Not yanmar.

 

No manual, but here is basic information and a picture.

http://global.yamaha-motor.com/showroom/cp/collection/marine_md-5y/

 

Excellent. Thanks for that.

 

It looks like this engine was first released in 1976. Here is a link from google Japan that has some exploded images of the engine. There is also an image of a manual that if you visit the page leads to an auction where you may be able to purchase it. Of course you will need to know how to read Japanese in order to use it.

https://www.google.co.jp/search?q=yamaha+md-5y&biw=1920&bih=993&tbm=isch&tbo=u&source=univ&sa=X&ved=0CC4QsARqFQoTCJmp9f3jnsgCFcSLDQodUSYMxg

 

Yanmar: 6SLY-STP 370 HP

Has anyone had an issue with a clunk coming from the engine while advancing the throttle from 1600 to 1800 RPM's? Once the problem occurs it can't be duplicated until the next day.