Onan 4k microquiet carb

Are you POSITIVE that you have the correct Carb for your Model AND SPEC number? Doug

Chris Bryant wrote:
I wonder if yours is California CARB unit.

Chris, ALL Onan Carbs are California compliant. Onan only builds Carbs that are California compliant. They have done so for over 25 years. They made the decision that it would be impossible to build a Carb for just 1 state. They would have no way to track where the 49 state models would go. Because of this is WHY you cannot buy Onan OEM Carb rebuild Kits for those built for the past 25 years. You can rebuild them, you just cannot buy the internal parts from Onan if you have a bad internal part. Doug

Chris Bryant wrote:
I wonder if yours is California CARB unit.

PS: Nice photos! Just a guess. Being a California compliant carb, it could be a float bowl vent which prevents unburned fuel vapors from venting to the atmosphere. Where does the other end go? The crankcase vent is a different line.

Chum lee

Thanks, I may try this!

Install the carb
Plug up the extra her from the crankcase, using a golf tee, or appropriate sizes vacuum line plug

Chris,

You believed Onan when they said that they don't have a service kit?
That is true, but if you go to a small engine shop, they probably do.
And yes, that looks like a crankcase breather and again, if you find a small engine shop, they will probably have a good idea what to do about it because they have seen so many without it.

Matt

Thanks for all the responses.

The RV was purchases in California.

I have an email into Onan to see about more information.

I wonder if yours is California CARB unit.

The hose could be a crankcase breather used to inject crankcase oil fumes back into the carb for burning. The hose looks like it is ported into the barrel of the carburetor. If your new one doesn't have the hose fitting, you could install the hose into your air cleaner. It would have the same function, that way.

carb has been updated the plug is,where that line use to go