Onan Carb Cleanup / 416-8

[boovuc 1,090]

I noticed my 416-8 plow tractor was sputtering when starting out under a load as though it was running lean. Sure enough........a little choke cured it so with the temps up a little on Sunday, I took the air cleaner assembly and heat shield off of it and took the top of the carb off. It really didn't look bad at all but I sprayed it all out and made sure the orifices allowed Seafoam through them. Fired it up and ran some more down it's throat but it still wasn't right even with the air cleaner assembly off. I took the main fuel mix needle out after seeing how many turns it was out and that was the issue. I sprayed Seafoam in that orifice with the nozzle in it five times before it broke loose. Put it back in and 1 and three quarters turns out and it made a huge difference. Actually gained RPM at full throttle. I took it out again and cleaned it out manually with a correct diameter feeler set I have.

Going forward, I'm pulling that main needle and spraying it first then checking for performance. That might be a Spring prerequisite for both my Onans. 

[WH nut 553]

^{Most of the time all you have to do is remove to top to give them a cleaning}

[Ed Kennell 42,111]

It is amazing how HAPPY   the Onan gets after a carb cleaning.

[boovuc 1,090]

"Most of the time all you have to do is remove to top to give them a cleaning"

 

That's what I have seen over the years also but this P216 and earlier in the summer, my P220 needed the main needle sprayed out! Both tractors have had new fuel lines in the past two years and the fuel filter changed every year. Maybe some bad fuel was run this summer in them. I don't know?

[546cowboy 302]

As everyone on here for any time should know, I really like Onans and especially the P-220's. As far as cleaning the carbs on the Onan's this is what has always worked for me. I pull the top off the carb and blow it out, then I fill the float bowl with the carb cleaner you would soak a carb in a basket, let it sit overnight and clean that out, blow out all the passages you can, fill with gas and put the top back on. I have never had a problem with one after that.

Edited December 30, 2014 by 546cowboy

[Tankman 3,523]

Only had the P220 '90 520-8 but, the carb does need cleanliness.

 

I now add either Seafoam or Berrymans to the gas cans when I fill 'em at the station.

 

Made / makes a great difference. Always Kohler but, really usin' the '90 520-8, Engine "sleeps" while working and I like how the engine sounds too.

 

Added PM (preventative maintenance) carb cleaning to my list!