OK, I looked at my machine.  There really isn't room to get a camera in there even with the cover above the fuel pump off.  And to take the cover off, the pump or lines needs to be removed.
So, I poked around the web.  Hoye has their own forum called YMOwners.  See this thread.
	
	
		
			
			
				
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					ymowners.com
				
 
			 
		 
	 
Another thread
	
	
		
			
				
			
			
				
				I'm working on a 1986 John Deere 850 tractor with a 3 cylinder Yanmar engine. The owners said it wouldn't start after not running it for a number years.  I removed the fuel tank, thoroughly washed it out, replaced all fuel lines, including the returns, replaced the fuel filter and O rings...
				
					
						
							 
						
					
					www.tractorbynet.com
				
 
			 
		 
	 
Some more insights
	
	
		
			
				
			
			
				
				
				
					
						
							 
						
					
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