Carburettor cleaning

[rudeafrican]

I need to clean the carbs on one of my 'rude 40hp as I'm not getting full rpm's on wot.I've stripped them down 3 times already with each time a slight improvement in performance. After the last time at wot, the rpm's briefly (split second) hit max then go back to +- 2000. <br /><br />I know that in order to clean a carb thoroughly, you need to soak it in a carb cleaner. Here is my problem, here in South Africa, the only carb cleaners available are in a spray can under pressure.(airosol) Could I use paint thinners to soak the carb in overnight and then use the thin nozzle and spray carb cleaner through all visable orifaces?<br /><br />Would the thinners a) clean out the blocked passages & b) damage the carb in any way?<br /><br />Thanks for your time

 

[NathanY]

Re: Carburettor cleaning

Can you buy the carb cleaner that you pour in the gas tank? That would work too. Im not sure about thinner, have never tried it.

 

[jim dozier]

Re: Carburettor cleaning

Lacquer thinner would work but you must be absolutely sure no plastic or rubber parts (only metal) are left in the carburetor while cleaning. Then replace all gaskets.

 

[rudeafrican]

Re: Carburettor cleaning

Thanx guys, <br />By rubber/plastic I presume you mean all o-rings, gaskets, washers, needle etc?<br /><br />I can get the petrol additive for cleaning carbs but at an enormous price for enough to soak to carbs in.

 

[Wkoch]

Re: Carburettor cleaning

If you have done this 3 times now wouldn't you think your problem is somewhere else? I'm no expert but did you try using a different prop? If you lower the pitch your RPM's will go up.

 

[SCO]

Re: Carburettor cleaning

I also have this question. Is OMC engine tuner good for carb clean?. It is more of a soap, and I imagine not as good a soaker, but you can pressure feed the fluid through the passages from the bowl to the jets etc. What about plain gasoline or acetone?

 

[dkondelik]

Re: Carburettor cleaning

I think I've had success soaking in mineral spirits, scrubbing with a tooth brush and blowing thru the channels & orafices with a can of the spray carb cleaner.<br /><br />Oh Yah, I think this works for cleaning a carb too.<br /><br />Good Luck<br />HAVE FUN!

 

[FlyBoyMark]

Re: Carburettor cleaning

Run the engine at nite with the cowel off and tell us if you you see fireflies around any of the ignition components under load in the water...Plug condition and gap? Fuel lines and tank? How about the fuel pump or any inline filters? Your problem sounds intermittant and I would start looking at the ignition system.

 

[Joe Reeves]

Re: Carburettor cleaning

RudeAfrican.... OMC "Engine Tuner" is an ideal carburetor cleaner if you have access to it. I have at times dismantled a carb, set the small parts in a small container, then sprayed those parts with the Engine Tuner. I also sprayed the carburetor body, the small passageways etc.<br /><br />I've found that this substance will clean the carb and its associated parts as good (if not better) than the commercial cleaner that usually comes in a 4 or 5 gallon pail. Give it a try.

 

[clanton]

Re: Carburettor cleaning

You can push a small copper wire thru the small brass tube, which is hard to clean. I also spray water thru all passages to insure they are open.

 

[rudeafrican]

Re: Carburettor cleaning

Thanks for the response guys. I'll answer each reply as best as I can.<br /><br />Wkoch. <br />Definately not the prop. Motor used to run 100 % then stood for a long time. Also the port (second)motor runs fine with same setup.<br /><br />Sco,<br /><br />Can get the OMC engine tuner, works out to about $21 after currency conversion.<br /><br />Klondike <br /><br />U must have the cleanest orrifaces in the 'hood!!<br /><br />Flyboy,<br /><br />Have done the running at night. No sparks etc. New Champions 78yc's gapped at .030. Timing set as per Joe's and manuals instructions. Was spot on to start with. VRO was rebuilt, no change.<br /><br />Joe & Clanton<br />Thanks, I'll bite the bullet and get a can, soak the parts and also use the thin copper wire up the tube.<br /><br />Once again, thanks for your time.

 

[FlyBoyMark]

Re: Carburettor cleaning

Dija spray some fuel into the carbs while under way to see if the engine picked up rpm?

 

[Andrew Brierley]

Re: Carburettor cleaning

What about fuel pump, are the carbs getting enough fuel to do their job in the first place?<br /><br />Try pumping the fuel bowl under full throttle to see if it picks up.<br /><br />Also, I have just had a lot of problems with Carbies, fuel lines, fuel bowl etc but at the end of the day my acceleration problem was a result of a bad thermostat and springs not allowing the motor to get to operating temperature. Main sympton was would only throttle up to about 1/3 power.<br /><br />Andrew<br /><br />Andrew

 

[Solittle]

Re: Carburettor cleaning

A suggestion - when you are through soaking the carbs take them to someone who has an industrial high pressure air compressor. Soaking will loosen the crud but will not get it out of the small passages that you cannot see. Also many carbs have what looks loke a small freeze plug which should be replaced. Crud gets behind them.