I have a nasty oil leak in my TB425CS. I can troubleshoot all the 'easy' stuff in my small motorized tools (spark plugs, fuel lines, carbs) but oil leaks are a new one to me. The unit is only a couple of years old. Where should I be looking for the leak? And HOW should I look for it?

Follow gas line from tank to carb. Observe bottom of carb. Remove screw holding carb bowl to carb. Clean bowl. Pinch off gas line with pliers. Ensure float falls down easily. Float up no fuel flow, float down fuel flow. Observe screw that hold carb bowl to carb, see if it has a whole thru it, clean with small wire, bread wrapper works good. Observe center fuel port, clean with wire. Remove pin that holds float and meter needle, clean port with wire. Reassemble. Ensure air filter is clean, oil is full, 30w oil, spark plug is clean and properly gapped. Replace air filter and spark plug once a year. Empty old oil out if any grey is observed in oil, this is moisture, can accumulate after winter storage. Clean out side of carb with carb cleaner to ensure choke can rotate freely. Always use Stabile in gas.
All newer mowers have a low oil shutoff.

Ensure clean fuel. Always use Stabile in fuel. Follow fuel line from fuel tan to carb, ensure no leaks. Remove carb fuel bowl to check float operation. Have pliers to crimp line or use fuel shut off valve. Remove carb float bowl and clean. Float should hang down freely gas should flow. Push float up gas should cut off. Replace spark plug, ensure plug wire snaps on tight. Clean or replace air filter. Ensure oil is full, 30w oil. All mowers have low oil shutoff.

hello sir, my machine will only start when pumping primmer bulb or squirting fluid in the carburetor than stops. the fuel line has broken off, in most small carburetors this is a ongoing problem.old fuel will crystallize when left in tank for a long time.plugging up ports, fuel lines, small screen in carburetor.fuel lines will dissolve clogging carb.this is why it will run when the choke is on creating a vaccum to where there is fuel forced in the carb to rum,also the gas will evoporate leaving the oil behind clogging up carb.the thing to do is remove carb. and clean out,replaceing gaskets or fuel line if necessory.use carb cleaner to clean out carb.make sure to make note where fuel line go.the fuel filter broke off of fuel line letting debris get in carb plugging it up.the muffler is known to clog up a lot on these machines where thay want run. the compression should be 60 to 120 lbs any thing below 60 is junk. when adjusting the carb screws turn in all the way than turnout 1 1/4 turns turn in slow untail machine runs also you need to check for spark by removing plug and grounding aginst engine to chech spark, ok.a new spark plug would be a good ideal too , if you are going to make these repairs use new fuel line and filter,hope this helps,any comments welcome,thank you, ``

hello sir, my machine will only start when pumping primmer bulb or squirting fluid in the carburetor than stops. the fuel line has broken off, in most small carburetors this is a ongoing problem.old fuel will crystallize when left in tank for a long time.plugging up ports, fuel lines, small screen in carburetor.fuel lines will dissolve clogging carb.this is why it will run when the choke is on creating a vaccum to where there is fuel forced in the carb to rum,also the gas will evoporate leaving the oil behind clogging up carb.the thing to do is remove carb. and clean out,replaceing gaskets or fuel line if necessory.use carb cleaner to clean out carb.make sure to make note where fuel line go.the fuel filter broke off of fuel line letting debris get in carb plugging it up.the muffler is known to clog up a lot on these machines where thay want run. the compression should be 60 to 120 lbs any thing below 60 is junk. when adjusting the carb screws turn in all the way than turnout 1 1/4 turns turn in slow untail machine runs also you need to check for spark by removing plug and grounding aginst engine to chech spark, ok.a new spark plug would be a good ideal too , if you are going to make these repairs use new fuel line and filter,hope this helps,any comments welcome,thank you, 11

hello sir, my machine will only start when pumping primmer bulb or squirting fluid in the carburetor than stops. the fuel line has broken off, in most small carburetors this is a ongoing problem.old fuel will crystallize when left in tank for a long time.plugging up ports, fuel lines, small screen in carburetor.fuel lines will dissolve clogging carb.this is why it will run when the choke is on creating a vacuum to where there is fuel forced in the carb to rum,also the gas will evaporate leaving the oil behind clogging up carb.the thing to do is remove carb. and clean out,replacing gaskets or fuel line if necessary.use carb cleaner to clean out carb.make sure to make note where fuel line go.the fuel filter broke off of fuel line letting debris get in carb plugging it up.the muffler is known to clog up a lot on these machines where they want run. the compression should be 60 to 120 lbs any thing below 60 is junk. when adjusting the carb screws turn in all the way than turnout 1 1/4 turns turn in slow until machine runs also you need to check for spark by removing plug and grounding against engine to check spark, ok.a new spark plug would be a good ideal too , if you are going to make these repairs use new fuel line and filter,hope this helps,any comments welcome,thank you, ff

It sounds like its time to have the carbuerator cleaned more then likely you have some varnish build up in the idle circuit. I cant remember if that bike has a fuel filter in line from the tank but if it does I would recommend changing that first as it could simply be starving the motor of fuel at idle.

It sounds like there may be an obstruction in the high-speed fuel circuit. You probably should clean the carburetor. Instead, you might try adjusting the high-speed fuel mixture adjusting screw to make it run a little richer. Before you do that, screw it all the way in, counting the turns and half turns, so that if you need to return it to the original position you will know how to do it. If adjusting doesn't work, you might remove the adjusting screw and shoot a little compressed air into the hole to dislodge any obstruction. But the best solution would be to clean the carb, because this type of machine sits idle for long periods of time and is prone to carb problems. I just had another though. The same symptoms happened to me, and it was caused by a thin layer or water at the bottom of the tank....and the water was only sucked up into the main jet at near-full-throttle. You could eliminate that possibility by tilting the trimmer to the side, and if it still died then water is not the problem.

Check and clean your spark arrestor located behind a diverter plate on outside of muffler. You'll need a #25 Torx, or one slot screwdriver and wrench to take the plate off. Clean it with carb cleaner and wire brush and re-install. If this screen gets clogged, it could lead to fuel spray coming out of carb throat. Clean and re-oil the sponge filter while you're at it. Hope it helps!

wheres the fuel ???
pluged line or carb may b

The engine is not getting enough fuel to the high speed jet. The issue may be one of the following:

1. Restricted fuel filter (in the fuel tank)
2. Pin hole in the fuel line (are bubbles seen traveling in the fuel line?).
3. Improperly mixed fuel/oil
4. Poor grade oil ~ never use outboard or genaric 2 cycle oil, use the manufactures oil or gold spectra (available at motorcycle shops).
5. Mal-adjusted carburetor, if you changed the brand oil you used in the past the carburetor may need to be readjusted to compensate, or switch back to the oil used before the issue occured.