Onan carb replacement

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SMan
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Joined: February 17th, 2015, 1:57 pm
Location: 7 Lakes, WA

Onan carb replacement

Post by SMan »

On another thread I mentioned I was going to replace the carb on my Onan generator. We bought our Chinook from a relative who purchased it new in 2004 and sold it to us in 2012 with 15K miles, so it spent most of its time sitting and hence the generator was never exercised as it should be. The generator never ran well and having dealt with my local Onan dealer on other motorhomes I decided the cheapest and easiest route would be to replace it myself. I picked one up on Amazon and installed it the other day. Took about 40 minutes (next time it will take 20 min ;)) and once installed it fired right up and runs great. Because I now have a spare carb I'll get a rebuild kit and keep it as a backup.
Steve aka SMan
2004 Premier V10
HereComesTrouble
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Joined: June 19th, 2016, 9:16 pm

Re: Onan carb replacement

Post by HereComesTrouble »

SMan wrote:On another thread I mentioned I was going to replace the carb on my Onan generator. We bought our Chinook from a relative who purchased it new in 2004 and sold it to us in 2012 with 15K miles, so it spent most of its time sitting and hence the generator was never exercised as it should be. The generator never ran well and having dealt with my local Onan dealer on other motorhomes I decided the cheapest and easiest route would be to replace it myself. I picked one up on Amazon and installed it the other day. Took about 40 minutes (next time it will take 20 min ;)) and once installed it fired right up and runs great. Because I now have a spare carb I'll get a rebuild kit and keep it as a backup.
A new KY carb for the 4000 watt Onan cost me $102 directly from Onan two years ago. They will not rebuild them for good reason. There are some extremely small passages which are almost impossible to clear. On a previous RV, I went the rebuild route. Had the carb off three times and still couldn't get it to run right after it had sat for several months without running. My time was worth more than the $100 I initially didn't wish to pay. I had that carb off so many times, I could take it off in the dark with my hands tied. Never again. $100 is cheap enough and when you're done, it runs like new.
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SMan
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Re: Onan carb replacement

Post by SMan »

Onan wanted $249.00 when I went there. If I could find one for $102 I'd buy it and carry it for a backup.
Steve aka SMan
2004 Premier V10
HereComesTrouble
Posts: 28
Joined: June 19th, 2016, 9:16 pm

Re: Onan carb replacement

Post by HereComesTrouble »

SMan wrote:Onan wanted $249.00 when I went there. If I could find one for $102 I'd buy it and carry it for a backup.
Where are you located? I bought mine from the Onan distributor in West Palm Beach. Of course, you need to use a little social engineering in order to get the best price on items like this. A company name and a tax number work wonders.
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SMan
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Re: Onan carb replacement

Post by SMan »

I live south of Seattle. I knew there had to be a catch for the $102. :lol:
Steve aka SMan
2004 Premier V10
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Re: Onan carb replacement

Post by Rokrover »

MTBE was the oxygenate of choice in unleaded gasoline before 2005 and the main problem then with old, stale fuel was gum plugging up tiny orifices in carburetors. Onan's recommendation for monthly exercise addressed this.

Now ethanol has become universal in pump gas, E10 being most common, there is the additional problem of corrosion of metal parts not long-term compatible with alcohol. E10 starts to turn bad after only 30 days and expires at 90 days, especially in humid climates. To counter this I use an appropriate fuel additive based on my experience with storing motorcycles over winter.

There are many fuel additives out there with various claims to extend fuel life and prevent problems but I won't make any commercial endorsements. Suffice to say I found a good product based on my review of its formulation ingredients listed on the MSDS, particularly those to protect against ethanol sulfate salt corrosion of fuel system metals.

The treatment rate is 10 oz / 30 gal and costs around $3.75 so you can decide if this would be economical, based on your driving / storage / repair history. I still exercise my Onan generator once a month as a precaution.
Ted C. / SW Arizona
"The Blue Chook" 2002 Concourse Owner: 2013-2019
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