I have a Cub Cadet LT1042 and it will idle great. When I push the throttle all the way up it boggs down and blows alot of smoke. Now if I take the air filter off (which is brand new) the mower runs great. Does anyone know what would cause this.
Take note of the position of the choke plate when this happens. Is this the Courage single engine?
Yes it is the Kohler Courage.
If your machine is set up with a combination throttle and choke control, be careful you are not accidentally choking the engine when going to full throttle (see your mnual for full explanation).
If you have a separate choke control, disregard...
BTW, what is the color of the smoke coming from the engine - light blue/gray or darker blackish ?
It has a separate choke control. The smoke is not black but is a dark gray.
does your engine have a air pre-cleaner and has it been cleaned/serviced at the same time that you replaced the air cleaner? and did this poor engine performance problem begin at the time of installing the new air filter?
I don't see a reply on the choke plate. If you can't confirm that you are shoving too much fuel though it, or have a sump that is contaminated w/ fuel- you will need to go onto other things such as the start of a valve rocker issue or flywheel key.
Yes the engine has a air pre-cleaner and it may have started when i serviced and replaced it but im not sure about that. What would that have to do with it?
depends on just how you serviced that precleaner. If done incorrectly, could restrict airflow, resulting in rich fuel mixture and running rough...
might want to chk your tractor or engine manuals for related procedure instructions and verify that all is OK .
Any ideas on air pre-cleaner? Not sure what I need to do to make it right
Possible you over oiled the pre filter restricting the air flow. Might have over oiled enough to get oil on the paper air filter and that will really restrict air flow. So will water left in the pre filter when cleaning.
Pull the pre filter off and see if the tractor runs better. If it does then you're on the right track. If it doesn't then remove the paper air filter and inspect it for signs of oil or water from the pre filter... in order for the air filter to work it has to be dry.
Cleaning pre filter is pretty simple... warm water and a little dishwashing liquid. Wring it out carefully when clean and let it air dry. Some L&G manufacturers call for lightly oiling the pre filter and some do not. Read your tractor manual. Also might want to get the engine manual from the engine manufacturer and see what they recommend for servicing the filter.