Assuming I do a tear down and remove the seals/plastics, has anyone had good or bad experiences with small engine carbs and acetone?I've got what I suspect is a gummed carb on my Onan 4K, after it had an unexpected time out where I couldn't exercise the gen monthly and didn't have an opportunity to drain the bowl.The gen runs, but surges under a load and dies usually after 20-30 minutes. I've tested the fuel pump and filter, and both seem to be fine, so I'm moving on to pulling the carb and doing a soak.

If that carb has a coating on the casting to seal the pores, the acetone might dissolve the coating and leave you with a hard cold-start situation. We called that a dry-bowl carb because all or most of the gas would seep out overnight. We would throw those carbs away. Go to the auto parts store and pick up some parts cleaner.

Why don't you try Seafoam mixed in a gallon of gas. Connect gas line to the gallon and let her rip.That should clean up the carb

Should not hurt the aluminum carb bodyBut acetone evaporates fairly quick and is highly flammableI find a bucket of parts cleaner from the auto parts store a better alternativeBut for one part one time I might use acetone

I'd just use a can of carb cleaner spray. If you need to soak it use new clean gasoline. The Acetone is way too strong IMHO.

X2 on carb cleaner. Small parts get soaked in cap from carb cleaner. Everything else a good spray down over a bucket. Then compressed air and blow out the passages. Watch for the seal on the needle and seat. Compressed air will force it out. Rinse repeat as necessary.JKaz

Soaking Onan Carb in Acetone? | Good Sam Community

58 Replies

Tom_Barb
Explorer
Sep 05, 2016
lane hog wrote:
Assuming I do a tear down and remove the seals/plastics, has anyone had good or bad experiences with small engine carbs and acetone?

I've got what I suspect is a gummed carb on my Onan 4K, after it had an unexpected time out where I couldn't exercise the gen monthly and didn't have an opportunity to drain the bowl.

The gen runs, but surges under a load and dies usually after 20-30 minutes. I've tested the fuel pump and filter, and both seem to be fine, so I'm moving on to pulling the carb and doing a soak.

These folks

Call and see what they say.
I've never seen any coatings on carb parts that will be harmed by Acetone, If they are painted on the outside that will come off, but who wold care?
Carb parts are usually white pot metal, and needs no extra coatings to make them fuel proof. In some cases the metal is etched with a 6% chromic acid this will leave a tea colored stain for better paint adhesion, that will not be removed by acetone.
2_many_2
Explorer III
Sep 05, 2016
darsben1 wrote:
Why don't you try Seafoam mixed in a gallon of gas. Connect gas line to the gallon and let her rip.
That should clean up the carb

X2
I have used Seafoam 50/50 this way with no ill effects. What have you got to lose?
K_Charles
Explorer
Sep 05, 2016
I also think carb cleaner would work the best.
kaz442
Explorer
Sep 05, 2016
X2 on carb cleaner. Small parts get soaked in cap from carb cleaner. Everything else a good spray down over a bucket. Then compressed air and blow out the passages. Watch for the seal on the needle and seat. Compressed air will force it out.
Rinse repeat as necessary.

JKaz
sch911
Explorer
Sep 05, 2016
I'd just use a can of carb cleaner spray. If you need to soak it use new clean gasoline. The Acetone is way too strong IMHO.
MrWizard
Moderator
Sep 05, 2016
Should not hurt the aluminum carb body
But acetone evaporates fairly quick and is highly flammable
I find a bucket of parts cleaner from the auto parts store a better alternative

But for one part one time I might use acetone
darsben1
Explorer
Sep 05, 2016
Why don't you try Seafoam mixed in a gallon of gas. Connect gas line to the gallon and let her rip.
That should clean up the carb
TakingThe5th
Explorer
Sep 05, 2016
If that carb has a coating on the casting to seal the pores, the acetone might dissolve the coating and leave you with a hard cold-start situation. We called that a dry-bowl carb because all or most of the gas would seep out overnight. We would throw those carbs away.

Go to the auto parts store and pick up some parts cleaner.

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Soaking Onan Carb in Acetone?

58 Replies

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