JoihnDeere LT166 Carb Problem

[MadMopar]

I have a JD LT166 that I just put a new carb from eBay (China) on. It starts up easily and runs but is blowing black smoke and 'sputters'. It stays running and even idles, just rough. Adjusting the one screw on the top doesn't have any effect. My altitude is around 5500'. I believe it is running too rich. I would like to rejet it, but don't have any idea what/where to get jets for it. Any help would be appreciated.

I have tried 2 eBay carbs with the same result.

 

[slomo]

Set the float level to a LOWER setting and test for power and proper running. So instead of the float being level with the carb bowl mounting flange, make it to where the fuel will shut off sooner. Float rides lower into the carb bowl when it shuts off the fuel flow.

OR get a high altitude main jet IF your carb has one available.

 

[bertsmobile1]

Take the air filter off and check that the choke is fully open with the throttle control in the run position.

 

[MadMopar]

Thanks for the replies.

Set the float level to a LOWER setting and test for power and proper running. So instead of the float being level with the carb bowl mounting flange, make it to where the fuel will shut off sooner. Float rides lower into the carb bowl when it shuts off the fuel flow.

OR get a high altitude main jet IF your carb has one available.

Maybe I'm being dense here, but I don't understand how setting the float lower will let the carb run leaner by allowing more airflow while into the mixture. Also, I was hoping someone would have an idea of where to get jets for these carbs.

Take the air filter off and check that the choke is fully open with the throttle control in the run position.

I am running it without the air filter installed right now. I figured that the less air restriction right now would be best. All controls are set correctly and working as far as I can see.

I'm pretty sure it's just running to rich because of altitude.

 

[slomo]

Lower float levels can make the engine run leaner. At 5500', you need a high altitude main jet. An HA jet has a SMALLER orfice than the regular or sea level main jet you already have. Your engine has code numbers to it. Look yours up specifically the carb. Look for a high altitude main jet for your carb. The higher the altitude the less fuel you need for a proper A/F ratio. There is less air at your house than most other folks.

Removing the air filter is for TESTING ONLY.

Stop buying ebay Chinese carbs. Put the OEM carb back on. Get a high altitude main jet for it. Clean/flush out your fuel tank and install ALL new hoses from tank to carb. Blow out tank with compressed air.

 

[StarTech]

Briggs 806634 (JD PN M144916). No guarantee it will fit the aftermarket carb.

 

[MadMopar]

Thanks for replies foiks.

Briggs 806634 (JD PN M144916). No guarantee it will fit the aftermarket carb.

Thanks for the part number. Unfortunately, I am using an after market (eBay-China) carb right now. I still have the original carb and I'm sure it has that in it since it used to run fine.

Lower float levels can make the engine run leaner. At 5500', you need a high altitude main jet. An HA jet has a SMALLER orfice than the regular or sea level main jet you already have. Your engine has code numbers to it. Look yours up specifically the carb. Look for a high altitude main jet for your carb. The higher the altitude the less fuel you need for a proper A/F ratio. There is less air at your house than most other folks.

I do know I need a HA jet. Wasn't aware that lowering the float could cause it to run lean. May try that.

Removing the air filter is for TESTING ONLY.

That's all I'm doing right now. I haven't left it running more than a minute. Too much smoke.

Stop buying ebay Chinese carbs. Put the OEM carb back on. Get a high altitude main jet for it. Clean/flush out your fuel tank and install ALL new hoses from tank to carb. Blow out tank with compressed air.

Have you priced a new carb for this? They are at a minimum $200. This thing is only used to pull a rake in the yard and maybe haul a trailer. I have a Craftsman that is capable of doing that also and we use that for mowing. I have pulled the deck on the LT166 and just want to use it to do misc stuff. It was built around 1998 (not sure) and I don't think it's worth that price just to do misc stuff. $30, I'm OK with.

After doing some further testing on the old carb, it's the fuel shutoff solenoid that isn't working. Again, replacement cost around $150. Same as above paragraph.

These prices are ridiculous and I just can't justify them.

I contacted the eBay seller and they don't have any jets for them.

Don't get me wrong, I do appreciate ya'll trying to help me but dumping $150+ into is hard to justify. I'm willing to work to fix it, but not dumping money into it when it's old and beat up. Previous owner(s) didn't treat it right. Even the hoods broken and has to be tied on.

 

[MadMopar]

As a follow-up, I have found cheap solenoids on eBay/Amazon but I don't know how to tell when this LT166 was built and there are 2 options listed. It looks like it may be the early model (of course).

Anyone know where I can look to find the build date?

Thanks again.

 

[MadMopar]

Here is what info I have on the Mower/Engine

John Deere LT166
B&S Vanguard
Engine 303777-1147-E
Fuel Shutoff Solenoid
947 806472 Used After Code Date 98062600
947B 807744 Used Before Code Date 98062700

 

[Tiger Small Engine]

Here is what info I have on the Mower/Engine

John Deere LT166
B&S Vanguard
Engine 303777-1147-E
Fuel Shutoff Solenoid
947 806472 Used After Code Date 98062600
947B 807744 Used Before Code Date 98062700

Bypass the anti afterfire solenoid on carburetor so you don’t have to spend $150 on part. Do not throw that OEM (probably Walbro) carburetor away. Measure bore where jet goes in and threads. Look around for smaller jets and buy a couple. Go smaller than you think and you can drill them out with micro drill bits until air/fuel mixture is correctly reached.