www.proxibid.com/Farm-Equipment-Machiner...on/75018166#topoflot 

Ok this one has me confused. Looks like a D318 engine but the hood is 4r or 5r, as well as the throttle. I can see what looks like the breather for the wet clutch, which fits with the direct start. Were is the air cleaner, the intake is visible but I am not seeing the air cleaner. The exhaust has me confused as well. Also the rails look very good with links that look rusted, but the idler looks way out at the end of adjustment. Or has the rain driven me around the bend.

It's a D4600 engine . air cleaner is on the right front corner of the engine under the hood.