H Muffler

I would use a very short automotive oval muffler, Or if bucks are not an issue, a welded stainless oval auto muffler. I would aim the muffler toward the driver with the off set clearing the air intake. then use an additional 90 bend to direc the exhaust down and to the left. I would build a support for the end to eliminate breakage of the manifold, or stressing of the threads on the existing pipe (usually an issue at some point anyway) my stout support {maybe chanel style fence post material} would bolt only to the frame rail, or other existing holes (never to the hood, or other sheet metal). It would be off set to clear all other parts and sheetmetal to stop rattles and wear.

My design deflects limbs up and off of the air cleaner, and catches fewer of them. It also will be far enough off of the hood to avoid scorching, and last it will be very quiet(which I and my neighbors like). There is also no need for a rain cap. Good luck with the project, let me know your solution. Jim Nicholson

1 – Simply run without a muffler. Unless you’re working the tractor hard the exhaust bark will tolerable. However hearing protection is still recommended. Downside is depending on the wind and direction of travel you will often be breathing exhaust fumes.

2 – The exhaust stack is a standard 2” iron pipe nipple. Simple matter to thread the outlet end of the nipple (see your local plumber and borrow his 2” NPT die). Then screw a 2” 90 deg elbow to the exhaust stack, then a second nipple into the elbow and finally the muffler pointing forward. Good idea to support the outlet end of the muffler over the radiator. Also if you have a nice paint job, a heat shield to protect the hood is a good idea (a piece of 6” galvanized stove pipe cut in half lengthwise and wired beneath the body of the muffler works nice). I've seen this done on a couple different H's - works nice and doesn't even look too bad.

3 – Swap the existing manifold for one from an O-4, OS-4, 300/350 utility, etc. These provide the exhaust outlet angled down at the front of the engine – exhaust exits over the governor housing. Problem is finding one in good shape. They’re not very common, and I doubt these manifolds are available today either from CIH or aftermarket.

Just be aware that laying the muffler down close to the hood will cause any paint near the muffler to get burned. If you've got a nice paint job, I wouldn't recommend it. Also, don't point it towards yourself.