morning workin on my oldest employees tractor for him.l3940 the pto engages dash says rpm .when you rev up it goes up .but when you put a load on the brush hog the blades slow down .But the gauge still reads the the right speed.thhe only thing this tractor has done is blow snow with a loader mounted hyd blower ,with a rear pto mounted hyd pump.any help please.
	
		
			
		
		
	
								 
				 
				
		 
 
		