Exmark Laser Z - starts fine and throttle's up fine, but doesn't have any power when trying to go up a slight incline without mower engaged. I have checked both plugs. ( firing clean, cocoa brown, checked both coils and reset gap. cleaned rust off of flywheel ) It's as if I'm not getting spark advance for the timing to fire on Top Dead Center when engine governor should advance the timing under load. This is the backup machine to my older ( same machine ) which had the same problem and which I just took to the dealer to let them figure it out !! All governor springs are intact. No on has ever touched them ! This machine has a Kawasaki engine, the older one in the dealer shop has a Kohler 27 Hp. I need my backup machine by thursday morning ! Any help would be appreciated !! IrishJO4
Exmark Laser Z - No power - feels like no spark advance
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bertsmobile1
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There are 7 variations of the lazer Z so for meaningful replies we really need the information off the mowers ID tag.
Assuming the engine is fine and the mower drives strait then your problem suggest a worn belt or insufficient belt tension
Never touched any eXmark but the Toros ( same company ) all have a grease nipple on the tensioner pivot that no one ever seems to bother applying grease to .
The arm must swing freely ( without the spring on ) and not hang up anywhere .
Assuming the engine is fine and the mower drives strait then your problem suggest a worn belt or insufficient belt tension
Never touched any eXmark but the Toros ( same company ) all have a grease nipple on the tensioner pivot that no one ever seems to bother applying grease to .
The arm must swing freely ( without the spring on ) and not hang up anywhere .
All belt tensioners are free & greased. Belts are in good condition. The engine is definitely the problem. Now, his other matching machine has the same problem. Both are Laser Z’s 2009 - but this one only has 700 hrs. on it. Engine just started doing this like the other machine- which is at the dealer now. loses power, Sputters, small backfire and then will gain its power back for 50’ and then sputter, small backfire , then RPM’s come up again. This one has original coil’s - both plugs are dry and Cocao
brown on electrode. Running Non-E gas in both machines !! I don’t have all the serial/ model numbers you want. Note- this machine has a Kawasaki engine.
If you run ethanol fuel, then over long-term (winter) storage, as the fuel separates and/or evaporates, it will leave a varnish-like coating on all the carb jets. This shrinks the effective diameter of all the carb jets... which leans out the fuel mixture. Since the engine's power comes directly from burning fuel, burning less fuel directly leads to less engine power. Obviously the smaller jets (the ones hardest to find and clean) clog first.
The carb will not "self clean". Disassembly is mandatory. Cleaning all the fuel paths is difficult.
Prevention is your best weapon. NEVER, EVER leave fuel in any engine with a carb for long periods. Not in mowers, trimmers, tillers, chain saws, etc. Empty all fuel from the tank, lines and carb before storage. No fuel = No problems.
The carb will not "self clean". Disassembly is mandatory. Cleaning all the fuel paths is difficult.
Prevention is your best weapon. NEVER, EVER leave fuel in any engine with a carb for long periods. Not in mowers, trimmers, tillers, chain saws, etc. Empty all fuel from the tank, lines and carb before storage. No fuel = No problems.
Yes, there's water. But there's also a brown varnish which will also be on the jets and other passages.
I didn't take the photo, and I wish it was better, but I'm just using what I got.
Agreed. Sucker is loaded up with varnish.
bertsmobile1
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Still waiting for a reply about which Z we are talking about and YES it does make a difference
Now if one went bad then the other went bad and they are different ages to me that screams BAD FUEL .
For the benefit of others reading this post
NEVER EVER CLEAN THE FLYWHEEL MAGNET
Magnetism goes right through rust , paint , paper , cardboard , dirt etc,etc,etc
You can actually damage the magnets at worst or just waste your time at best .
Now if one went bad then the other went bad and they are different ages to me that screams BAD FUEL .
For the benefit of others reading this post
NEVER EVER CLEAN THE FLYWHEEL MAGNET
Magnetism goes right through rust , paint , paper , cardboard , dirt etc,etc,etc
You can actually damage the magnets at worst or just waste your time at best .
The problem with ethanol is how it carries water in suspension rather than letting the water sink to the bottom where it can be decanted.
Ethanol carries water into the fuel system where it can do damage from suspension same as not. Corrosion. Varnish. Etc.
Ethanol will not separate from gasoline without being saturated with water.
There is no additive which isn't in effect the same as "more ethanol" to "treat" ethanol in gasoline. If the problem is "separation" then it is a mistake to use an additive which "solves" this problem by allowing more water to be carried in suspension. May end the separation but the water is still there. And when water is present there is less gasoline resulting in a leaner mixture. Same thing happens with premix oil. Engine runs leaner with 40:1 than 60:1.
Sealed automotive fuel systems with evaporative controls have much less trouble with water condensation in the fuel than open small engine fuel systems and gas cans.
Ethanol carries water into the fuel system where it can do damage from suspension same as not. Corrosion. Varnish. Etc.
Ethanol will not separate from gasoline without being saturated with water.
There is no additive which isn't in effect the same as "more ethanol" to "treat" ethanol in gasoline. If the problem is "separation" then it is a mistake to use an additive which "solves" this problem by allowing more water to be carried in suspension. May end the separation but the water is still there. And when water is present there is less gasoline resulting in a leaner mixture. Same thing happens with premix oil. Engine runs leaner with 40:1 than 60:1.
Sealed automotive fuel systems with evaporative controls have much less trouble with water condensation in the fuel than open small engine fuel systems and gas cans.