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

GoPackGo
Explorer
Sep 05, 2016
Gunk sells a really nice carb cleaner kit consisting of a bucket of parts cleaner solvent and a self-contained basket. That's what you want. Not acetone.
midnightsadie
Explorer II
Sep 05, 2016
BEFORE you take any thing apart do the sea foam carb cleaner it has directions on the bottle sea foam has cleaned up meney boat motos from gunk. and never taken of the boat. wal mart $7.00 bucks or less
Toddupton
Explorer
Sep 05, 2016
lane hog wrote:
Guys, I asked about Acetone. Not carb cleaner or Seafoam... ;)

Wow! Really?
352
Explorer
Sep 05, 2016
Sea Foam will do it. It did for me in my tractor and mowers.
raross61
Explorer
Sep 05, 2016
I would highly suggest you have the carburetor ultrasonically cleaned, almost all the newer small carbs have a coating on them! Almost all shops have one for these smaller carbs, and they work great! BoB
Sam_Spade
Explorer
Sep 05, 2016
lane hog wrote:
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.

Totally unnecessary to do all that work.....probably.

Get some Berryman's B12 Chemtool. It is made to be a carb cleaner.

Given the tests that you have already done, you should be able to get a healthy dose of that into the carb while on the machine to soak right there.

A 50/50 mix with gas fed into the fuel pump intake until it stumbles a little should do the trick.

Let it sit overnight and then run it normally for a bit to see if it is better. If it IS, put a recommended dose of B12 in the regular gas supply and pray.

When I got mine it had been neglected so bad that two attempts at professional cleaning failed and it required a new carb; about $250 installed at a Cummins dealer. I enjoyed screwing with things like that when I was younger; NO MORE. It's been running like a top with it's new carb. Well worth the money.
lane_hog
Explorer II
Sep 05, 2016
Toddupton wrote:
lane hog wrote:
Guys, I asked about Acetone. Not carb cleaner or Seafoam... ;)

Wow! Really?

Yes, really. I know the norm on forums is to ignore the original question, but I thought I asked a fairly targeted question. But, happy to restate if it wasn't clear enough...

I'm already planning to doing a tear down -- it's a ten year old carb, and I know there's going to be gunk inside. If it's off the block, the tear down will be followed by a soak.

I'm looking for advice on what to soak it in, not for what additive to put in the fuel, or how to clean it while it's running.
Sam_Spade
Explorer
Sep 05, 2016
darsben1 wrote:
Why don't you try Seafoam mixed in a gallon of gas.

Seafoam is a marine fuel stabilizer.
As a carb cleaner, it is overpriced snake oil.

Berryman's B12 Chemtool or Gumout are much better.
lane_hog
Explorer II
Sep 05, 2016
Sam Spade wrote:
lane hog wrote:
Guys, I asked about Acetone. Not carb cleaner or Seafoam... ;)

And the answer, from several people, is:
NO, do not use acetone.

That's not what the answer has been. I get that a lot of people like Seafoam.

I'm asking if anyone has tried acetone (which is one of the main components in B12).
Gdetrailer
Explorer III
Sep 05, 2016
lane hog wrote:
Sam Spade wrote:
lane hog wrote:
Guys, I asked about Acetone. Not carb cleaner or Seafoam... ;)

And the answer, from several people, is:
NO, do not use acetone.

That's not what the answer has been. I get that a lot of people like Seafoam.

I'm asking if anyone has tried acetone (which is one of the main components in B12).

The answer is still NO, NO to acetone by it's self.

Clearly you do not understand just how to clean a carb.

The problem you have is THE MAIN JET has gotten clogged.

In most small engine carbs the main jet is accessed by removing the carb bowl.. The jet is typically housed in the little stem that the carb bowl screw goes into.

Most main jets can be removed via a flat blade screw driver.

You remove the jet, and using a SPRAY CAN of CARB CLEANER you FORCE the built up junk out of the jet..

No soaking needed and if you do it correctly you do not need to remove the carb..

Not to mention straight acetone is highly flammable, evaporates almost instantly which makes it an extremely POOR CHOICE to use as a soaking liquid.

You would have to have a completely air tight container in order to be able to use acetone.. Just not worth the hassle, there ARE better ways to clean a carb.