I own a 2005 exmark lazer z 60. I bought this mower brand new and I am the only operator. The mower just turned twelve-hundred hours. So here is the problem. When I engage the collection system the mower really boggs down and the rpms drop to a point of almost stalling but work their way up to about thirty-five hundred rpm. Whenever a go up any incline the mower will loose rpm and stall if I don't turn away and get to a more level plain. This has been going on all this season. Up until this season it has run fine. I have re-built the ultra vac, checked all pulleys they spin freely. The engine has a new short block, carburetor, new heads, new clutch. The hydraulics checked out and are within factory specs. No one can seem to figure out what is causing this problem. I had it checked out at the certification school for kohler engines. They suggested to take to my exmark dealer. They won't be able to look at it until March because they have not seen the machine since I bought it. My local mechanic and the kohler people have never run into this before. Thet are stumped. Any help would be appreciated.
How do you fix this??
- Thread starter shelley
- Start date
bertsmobile1
Lawn Royalty
Sounds very much like a governor problem in particular a frozen governor not allowing the throttle to open up when a load is applied to the motor.
Get some one to sit in the seat and turn the blades & vac on and off.
you should see the thrttle opening up wide as the engine bogs down.
Get some one to sit in the seat and turn the blades & vac on and off.
you should see the thrttle opening up wide as the engine bogs down.
Yes it does.
ILENGINE
Lawn Royalty
I don't know how to explain this but just listen to the engine while its running. Does it sound like it is running on one cylinder. Your issues sounds like a power loss which could be an engine on one cylinder. You may be able to listen to another twin cylinder engine that is running correctly and then compare it to yours. Doesn't matter what brand, most of the engines sound the same on one cylinder
Lack of a better description, an engine on one cylinder sounds throaty.
Lack of a better description, an engine on one cylinder sounds throaty.
The engine is brand new. Leak down test and vacuum test have been done and there are no issues with the engine.
reynoldston
Lawn Pro
I find that the eases way to know if it is running on one cylinder or two is the heat of the exhaust pipe. I agree with bertsmobile is the governor working or is the engine losing power which could be a number of things. As I recall a new short block comes as a striped down block.
So here is what happens. With the mower going at full ground speed(about 10 mph) as soon as I engage the pto the mower slows down so fast I almost fall forward off the machine. As the rpms pick up the ground speed at best is about 6 mph. If I go up any incline it slows almost to a full stop. If I disengage the pto there does't seem to be any problem as far as a normal operation. If I take off the collection system the mower will operate normal.It has seem to stump anyone who has looked at it.
reynoldston
Lawn Pro
If this is stumping experience mechanics that are working on it sure has me stumped when I can't even see or hear the machine.
I posted this hoping some one may have experienced a similer problem.