Installing a new Carburetor on a Cub Cadet ST 100 field trimmer mower 

Thanks for posting this. I couldn't figure out how to get the linkage out. Your instruction helped alot. This carburetor is such a bad design. Mine only lasted one season. It might be worth it to buy ethynol free gas, which were I live can only be bought at Home Depot in those small cans. I believe the linkage and plastic flap thing is part of the automatic choke system. As the RPMs increase, the airflow moves the white plastic paddle; and through the linkage releases the choke. Your ST100 looks brand new! You must take really good care of it.

You have the best video on this process on internet...very helpful.

For the love of god, THANK YOU FOR HAVING A STILL CAMERA!!! I was able to see what I did wrong, other videos it's like the person had the canera mounted on their wrist...

Forgot to say that hooked up the auto choke wrong and you really showed how it needed to be installed! Thanks!

Very nice video man … well thought out and informative. Your observations about ethanol-free gas are spot on … been running all my new equipment that way, and dealing with the holdovers until maintenance/replacement. ✌🏻

Great help pulling it out. A tip for whoever is doing this after you get the carb back in. Make sure all those moving parts can swivel easily. I ran into a weird problem with the one in the back. (with the spring) It wouldn't turn freely. I kept thinking I did something wrong. I ended up pulling the carb back off. And it still wouldn't move. So turns out it had alot of build up which was keeping it from spinning. I had to remove the tiny bolt holding the butterfly plate on. Then the pin slides out. Then I used I tiny flat head and got all the gunk out. Put the pin back and it spun freely. Put everything back on... Bam motor running back to normal.

Thanks for the video! This video helped me figure out that there was a linkage piece installed incorrectly on my ST-100 causing it to not want to start up. Got it running like a top now

Thanks for your video! I bought a used Cub Cadet trimmer like yours a few months ago really cheap. I struggled to get it started so I put on a new carb. It still would not start and I spent hours trying to get it to run. I finally found a manual on the engine and discovered there is a tiny inline fuel filter that is in the outlet tube of the fuel tank! I removed that filter and the engine will now start and run! Pull that filter out and add a real fuel filter in line on the fuel line!!

Thank you so much for this time saving video. I can now put the lawnmower back together correct ly

Sure glad i saw this step by step video. I will most likely be buying a new carb for mine.

Thank you for helping me reassemble my Cub Cadet ST 100. 👍👍👍👍👍

Worked great - thank you for taking the time to make this!

Very good step by step tutorial!

Thank you sir! Good tutorial for beginners and HD video.Good job!

I have heard that the additive STA BIL will cause the carb bowl to do this. My SC 100 mower did the same thing as yours. When I pulled the bowl off the carb it looked worse than yours did. I just put a new carb on my mower and it started right up with no problems.

Got me up and running after watching the video... thx for the demo

nice video i feel confident replacing the carb on my trimmer now!

Dont throw the old carb out, you can soak it in straight Pine-Sol and use a bread tie wire to run thru the center of the jet and blow air to finish...now ya got another spare carb. Soak the bowl in vinegar and even sand, wire brush, or sandblast the inside of the bowl. Thank you for a great video.

exactly what i needed. thanks a million!

You are the man, thanks for the great video sir!!

Great video. I'm having the same problem with my Cub Cadet two-wheeled trimmer. A 10mm ratchet wrench would help with removing that white vane gadget if there's room for it.

Thanks for posting helped out a lot

Thank you, that was very helpful!

Great video helped me a lot very detailed thank you

Very informative. Thank you!

Thanks alot for taking the time and posting this video. I'm having g to swap out carburetor. Where can I order it?? 👍💪😎

Outstanding video, I had trouble with my string trimmer the first took the bowl off and it was full of debris gave up on taking carb off but I wont the next time. I installed the same kind of fuel shut off but it does not turn freely almost like its gaulding any idea what could be causing this I think I purchased 12 of them from Amazon.

Awesome. Thanks for this. The throttle seems to be stuck all the way up. On this cub cadet. Not sure how to adjust it. Bless u

That thing looks brand new

I just picked one of these trimmers up from my neighbor. Followed your directions to the T, 2 pulls and it started but only seems to run at an idle. I'm guessing that's how it's supposed to run.?? Can you help?

@starastronomer do you know where to purchase the inline fuel shut off valve

@starastronomer is it possible my machine won’t run with ethanol mix fuels? It quit last year after I forgot to drain the old fuel

Great video. Just what I was looking for! Can someone pls. tell me where the two lines for the carbon cannister attach to? When I removed the engine shroud, one came loose. The other is attached to the back of the air filter housing, and from this video it looks like the other goes towards the fuel tank. That makes sense base on carbon cannisters on cars that I have worked on, but I don't see where it goes. Note to anyone from Cub Cadet who is reading this: it would really help if your parts manual also showed where items connect to each other.

Can you drain the carb bowl without removing it?

Thanks

Still need a fuel filter also

How do you keep It so clean. Mine has lasted at least 5 yrs or more and used on 20 acres with lots of brush. Will never look like yours.

@starastronomer I’ve followed this tutorial to the letter and mine won’t run it all. It fires off ether but dies immediately. There’s fuel in the carb bowl. I have a new carb on the way. FYI the carb has been blown out with carb cleaner. The main jet is clear, the float works fine the pilot is clean and the mid range jet is clean. I’m stumped

Folks take a picture or two before you tare it apart of linkage

The drain on the carburetor is a poor design. It doesn't drain to the bottom of the bowl. It leaves a little gas in it. I think what you were seeing was varnish from dried gasoline not rust. Being that there is no iron/steel in the system it wasn't rust. If you want to drain all the gas out of the carb, you need to take the bottom bolt out. This holds the bowl on, but nothing will fall out of the carb.

Carb is so easy to clean why replace it Just wash out with carb cleaner good