Carburetor rebuild project.

[Brian Ski]

Neighbor came by with a pressure washer asking if I wanted it. It was stored for a long time. I said I will take a look at it. Not sure if anyone here rebuilds carbs. Most things that use gas if not drained and ran dry, when stored for a while, the carburetor will plug up and they will not run. The fuel tank was about 3/4s full it smelled bad. I am guessing the fuel was sitting in it over 5 years.

Here is the inside of the fuel tank after being drained and taking out the anti slosh sponge. (yes some nails and other bench stuff tossed in to help scrub it)


This is what I got out of the tank. Degraded sponge and varnished fuel.


This is after it was cleaned. Not perfect but quite usable.


Main jet was plugged up solid. Picked screen was pretty bad also.


Here it is all cleaned up. Just have to make sure main jet is cleaned out but do not ream it out to make the hole larger or it will never run correctly again. Spray it out completely with carb cleaner to rinse it out and make sure all the ports are open.


Help with a new gasket set and put it all back together.

Here it is all assembled. Gave it a few pulls and it runs great. Actually runs better than my new one.


A few tips..

Do Not force anything. Lots of small fragile parts. If the parts won't move hit them with carb cleaner and let is set a couple minutes. Then keep rinsing them so they work freely.

Take a couple pictures with a digital camera (or draw a detail diagram) of the linkages and where the springs go. Hard to remember where they came off.

[geezer]

Been there done that many times,,,,most small engine problems relate back to inactivity on the motors,,,after a while the gas turns to jelly and plugs up the small idle orfices and the motor will never start or idle properly,,,little motors should be run every so often to make fresh gas flow into the carb,,,small motors should be run on premium gas,,,,they preform better on that..Sometimes there only way to get the gunk out of the carb is to take it apart and use a needle to pick out the rubberized gas..reassemble it and it runs like a new machine...Snowblowers and lawnmowers that sit idle through the season are the main problems,,,should run the motors every month for a few minutes to avoid problems..

[Rivets]

...Snowblowers and lawnmowers that sit idle through the season are the main problems,,,should run the motors every month for a few minutes to avoid problems..

Or put fuel stabilizer in the gas tank and run the engine for a few minutes before storing. Add engine storage spray in the cylinder(s) and you're golden. And fresh oil of course.

rivets

[Brian Ski]

Or put fuel stabilizer in the gas tank and run the engine for a few minutes before storing. Add engine storage spray in the cylinder(s) and you're golden. And fresh oil of course.

rivets

Last winter had a buddy bring his snow blower over... He is very religious about adding stabil all the time. Float bowl was gummed up. It does work but the fuels lately seem to have a shorter shelf life. He looked at me and said I use stabil all the time.

I have had snowmobiles for decades. At the end of each season the very best thing was to fire them up get them running. Shut it down, disconnect the fuel line, siphon or pump the fuel out of the tank, and then fire it up. When it starts to bog down hit the choke. It will then kick back up and suck all the fuel out of the float bowl. I have been doing this for a long time and the next season or a couple down the road dump in new gas and it fires right up.

The hard part is getting off your butt and doing it at the end of the season instead of just shoving it in the corner.

[Brian Ski]

Snowblowers and lawnmowers that sit idle through the season are the main problems,,,should run the motors every month for a few minutes to avoid problems..

Yea same thing with chainsaws and snowmobiles. Mowers are not quite as bad, because the seasons are longer. You may park a snowblower in January and not run it again until December.

BTW I heard the life expectancy of a consumer owned chainsaw is 2 years. They will buy a new one and run it for a while to cut up some new fallen trees or branches. Then toss it in the garage and a couple year later pull it out and it won't start. Then are you going to pay $50 to 75 to get someone to fix it or drop another $100 and get a new one???

Hate to say it but I have a 16" McCullough and it is over 25 years old. It has cut a LOT of wood. I think I have bought 3 or 4 bars for it. Keeps wearing them out.

[posixPilot]

Do Not force anything. Lots of small fragile parts. If the parts won't move hit them with carb cleaner and let is set a couple minutes. Then keep rinsing them so they work freely.

I had a problem at the end of last season with my normally reliable Honda lawn mower ... It would stall every time it ran it up a hill. I assumed it was due to dirt clogging a jet, so I disassembled the carb and cleaned it. However, I was afraid to use carb cleaner, since the float and the valve looked like they were made from acetal plastic, and I didn't want to risk melting them. Any of you guys have problems with the cleaner eating up gaskets or plastics pieces?

Thanks
Mike

[geezer]

I had a problem at the end of last season with my normally reliable Honda lawn mower ... It would stall every time it ran it up a hill. I assumed it was due to dirt clogging a jet, so I disassembled the carb and cleaned it. However, I was afraid to use carb cleaner, since the float and the valve looked like they were made from acetal plastic, and I didn't want to risk melting them. Any of you guys have problems with the cleaner eating up gaskets or plastics pieces?

Thanks
Mike

Yep,,,use hot water and and air blower for a lot of the small carb holes,,,some cleaners will eat the metal,,,another problem that can really screw a small engine up from sitting too long is having the exhaust valves seize in the head,,,,then the push rods bend as you crank it over,,,the motor will never start after that,,,bought a ATV with that problem ,,,,a 15 dollar fix,,,and I had a bargain unit for 2,000 less than the current market value on it....Luv people who don't do squat with maintaining their stuff...they get frustrated and almost give it away..

[Brian Ski]

Any of you guys have problems with the cleaner eating up gaskets or plastics pieces?

Thanks
Mike

No problems with any floats or needles with the viton tips. But I usually spray and wipe them off with a paper towel or a good blast of air.

BUT do not hit the primer button or the little yellow plastic fuel lines. They will turn to jello fast and fall apart. Not many on small carbs, but any rubber O rings will swell up and get wiped out with the carb cleaner.

I know it is scary some time tearing a carb down all the way but it is the best way to clean it out. I remember the first 4 barrel quadrajet I rebuilt. I took it to a older neighbor who had a chemical solvent tank. (Not a parts cleaner... Was for carbs only) he handed it back nice and shiny, then gave me a baggy with all the parts I didn't take off. You know the ones you are not sure how to put back on so you didn't take them off... Hahahaha


You are talking about the white plastic elbow and float??? They seem to hold up to the solvents. I have been pretty good at a quick n dirty carb cleaning. I will take the mower or what ever and put it on the bench. Unscrew the float bowl nut and pop the bowl off, wipe it out and rinse it out with carb clean and shoot it right up the main jet and pop it back together. Unless it is really bad. Then it takes some elbow grease.

[posixPilot]

Yep,,,use hot water and and air blower for a lot of the small carb holes,,,

That's exactly what I ended up doing ... Seems a bit counter intuitive cleaning a carb with water .

You are talking about the white plastic elbow and float??? They seem to hold up to the solvents. I have been pretty good at a quick n dirty carb cleaning. I will take the mower or what ever and put it on the bench. Unscrew the float bowl nut and pop the bowl off, wipe it out and rinse it out with carb clean and shoot it right up the main jet and pop it back together. Unless it is really bad. Then it takes some elbow grease.

Yeah, mine had a white plastic horseshoe shaped float, and a tiny torpedo shaped valve also made out of plastic. The valve also had a small rubber seat gasket as I recall, and those were the pieces I was really concerned with. I ended up taking the carb completely off the mower and disassembling it to get it clean. Glad I did, as a couple of small parts popped lose as soon as I removed the float, and I never would have found them otherwise.

Cheers
Mike

[Brian Ski]

That's exactly what I ended up doing ... Seems a bit counter intuitive cleaning a carb with water .



Yeah, mine had a white plastic horseshoe shaped float, and a tiny torpedo shaped valve also made out of plastic. The valve also had a small rubber seat gasket as I recall, and those were the pieces I was really concerned with. I ended up taking the carb completely off the mower and disassembling it to get it clean. Glad I did, as a couple of small parts popped lose as soon as I removed the float, and I never would have found them otherwise.

Cheers
Mike

They did have a great water based solvent years ago but somehow it disappeared. Worked better than the carb cleaner.

That needle with the little spring. Tough to put back while the carb is still on the motor... But after you do it quite a few times you can get a handle on doing it.