Smokes when cold and using the choke!

john in ohio

Active Member
Spring mower tune up
Two riding mowers, both smoke when cold and using the choke! Smoke stops when the choke is off.
I use ethanol free gas.

YTH1542XP with a Kawasaki FH430V 954568465

Husqvarna TS348XD (48") 24HP Kawasaki FR730V
CODE: FR730V-GS04-R
E/NO: FR730VE37822
S/N: L2009140331
 
Hello J.,

A choke enrichens the fuel/air mixture for easier cold starting but will make an engine smoke until the choke is turned off. Don't expect "more power" by using the choke.

Using Ethanol free gas simply prevents excessive moisture from being absorbed into it and creating carburetor problem.
 
It doesn't start with out choking for a few seconds. The first couple years of use it had no smoke when starting. The smoke alarmed me and I was just trying to understand why it was now smoking.
 
Hello J.,

Is it prolonged cranking with black smoke? That usually means the choke is sticking on, or a dirty air cleaner issue. A little simple linkage cleaning will usually resolve the issue or an air cleaner replacement.

Is it blue smoke? Possibly needs the oil checked for excessive level or raw fuel thinning it out. Maybe the carburetors need a simple cleaning. I do not suggest ordering any aftermarket carburetors because they typically create other problems because they do not come calibrated to your specific engine design. (Just because it fits, does not mean it works)

A cold start of blue smoke then it clears up is possibly failing valve guide seals. They do get brittle and stiff with age. There are videos of how to replace them in online videos, but it takes some intermediate mechanical skills and the correct tools.

If it where a serious wear issue like stuck piston rings or cylinder scoring smoke would continue at all speeds, especially under load.
 
Hello J.,

Is it prolonged cranking with black smoke? That usually means the choke is sticking on, or a dirty air cleaner issue. A little simple linkage cleaning will usually resolve the issue or an air cleaner replacement.

Is it blue smoke? Possibly needs the oil checked for excessive level or raw fuel thinning it out. Maybe the carburetors need a simple cleaning. I do not suggest ordering any aftermarket carburetors because they typically create other problems because they do not come calibrated to your specific engine design. (Just because it fits, does not mean it works)

A cold start of blue smoke then it clears up is possibly failing valve guide seals. They do get brittle and stiff with age. There are videos of how to replace them in online videos, but it takes some intermediate mechanical skills and the correct tools.

If it where a serious wear issue like stuck piston rings or cylinder scoring smoke would continue at all speeds, especially under load.
Smoke is white, I also noticed when doing my spring oil change, I'm getting gas into my oil!
I picked up an ultra sonic cleaner after reading more on this forum and I've pulled the carb to clean it.
I'm picking up a new float valve today, along with gaskets and o-ring for the bowl. I hope I can do this, I'm concerned about getting back together. The springs and wires going to the governor! What a pain.
 
Hello J.,

Is it prolonged cranking with black smoke? That usually means the choke is sticking on, or a dirty air cleaner issue. A little simple linkage cleaning will usually resolve the issue or an air cleaner replacement.

Is it blue smoke? Possibly needs the oil checked for excessive level or raw fuel thinning it out. Maybe the carburetors need a simple cleaning. I do not suggest ordering any aftermarket carburetors because they typically create other problems because they do not come calibrated to your specific engine design. (Just because it fits, does not mean it works)

A cold start of blue smoke then it clears up is possibly failing valve guide seals. They do get brittle and stiff with age. There are videos of how to replace them in online videos, but it takes some intermediate mechanical skills and the correct tools.

If it where a serious wear issue like stuck piston rings or cylinder scoring smoke would continue at all speeds, especially under load.
Smoke is white, I also noticed when doing my spring oil change, I'm getting gas into my oil!
I picked up an ultra sonic cleaner after reading more on this forum and I've pulled the carb to clean it.
I'm picking up a new float valve today, along with gaskets and o-ring for the bowl. I hope I can do this, I'm concerned about getting back together. The springs and wires going to the governor! What a pain.
 
Smoke is white, I also noticed when doing my spring oil change, I'm getting gas into my oil!
I picked up an ultra sonic cleaner after reading more on this forum and I've pulled the carb to clean it.
I'm picking up a new float valve today, along with gaskets and o-ring for the bowl. I hope I can do this, I'm concerned about getting back together. The springs and wires going to the governor! What a pain.
Hi John,

Take your time and you will be fine.

As for the governor, do not attempt any adjustment to the factory setting. People tend to tinker with them because they don't understand how they work. A governor is used to control top engine running speed to protect the engine
 
The smoke alarmed me and I was just trying to understand why it was now smoking.
If this engine is say 5-7 years old or older, time to de-carbon the cylinder/s. Why? Chunks of carbon can and WILL flake off and get between the piston and bore. This is where all the scratches come from we see in the bores. Leads to using oil and smoking as yours is doing.

Perfect time to CLEAN the cooling fins and entire block, clean and adjust the valves, check for strong spark and so on.

Yes this is in EVERY air cooled small engine manual out there. Yours and mine included.
 
Back
Top