Onan Missing When Cold / Where to get parts?

[decksetter 50]

My dad's 416H is running like crap when it's cold. It usually starts, but is very clearly running on one cylinder until it's warm. Once it gets up to temperature, it usually runs perfect like it's not missing at all.

Does this sound like a valve issue or carb issue or??? Tractor has around 1100 hours.

Also, where can I get parts for this tractor? It needs a muffler and air filter at least, but the local mower shop that used to deal in Wheel Horse swears up and down you can't get parts anymore.

[zieg72 209]

I would confirm that you have compression in both cylinders when it is cold. You may just need a new spark plug. If you have a sticking valve it will more than likely be your rear cylinder. Check it out and let us know. Some parts are getting scarce but still should be available.

[decksetter 50]

I would confirm that you have compression in both cylinders when it is cold. You may just need a new spark plug. If you have a sticking valve it will more than likely be your rear cylinder. Check it out and let us know. Some parts are getting scarce but still should be available.

Been a busy week, haven't had time to check compression yet. Going to try and track down a compression tester this weekend. I'm pretty sure my dad already replaced the spark plugs.