10 Year Old Raptor Bogging Down

bertsmobile1

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The problem with not diagnosing the malfunction in the first place is any or all of the parts replaced could be faulty or could have been installed incorrectly
Every thing you replaced is now considered faulty till proven to be good .
Have you checked the valve lash yet ?
have you checked that the valves are opening & closing yet ?
have you checked that both valves are at the same heights ?
 

rrichar1

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The problem with not diagnosing the malfunction in the first place is any or all of the parts replaced could be faulty or could have been installed incorrectly
Every thing you replaced is now considered faulty till proven to be good .
Have you checked the valve lash yet ?
have you checked that the valves are opening & closing yet ?
have you checked that both valves are at the same heights ?
No, I personally don’t have the mechanical skill set to do that and the first person who worked on it for me is my son in laws father who is a car mechanic and restored cars for a living who said the “compression is good” is that not proof of valve lash soundness? Granted he’s not a dedicated lawn mower repair mechanic like y’all but I trust him.

Thanks for the input and guidance.
 

slomo

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that bogs down under load in high grass and I have to slow down to let it recover
That tells me you need to cut more often or slow down.

Take a picture of the lawn. Want to see what kind of grass you have. And show us how tall it is when you cut.
 

rrichar1

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That tells me you need to cut more often or slow down.

Take a picture of the lawn. Want to see what kind of grass you have. And show us how tall it is when you cut.
I will but I just mowed what there was today with my other hustler raptor with the Kohler engine but we are in a severe drought here in Galveston county in Texas so all the San Augustine grass is dying. This raptor (unlike the problem raptor with the Kawasaki) is set at the third lowest setting and just plows through it easily. The Kawi raptor never struggled at the same setting until this year. And it’s not tall at all, I would say 4-5 inches/whatever a normal week growth is. I don’t let it get real high.
 

hlw49

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Good compression check does not indicate you don't have a valve problem. Say you have a push rod off or a worn cam lobe it can still have good compression. Have you tried pulling one plug wire at a time to see if it is hitting one both cylinders.
 

bertsmobile1

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Kawasaki have their service manuals on line as a free download
Should have the parts list there as well but it takes a bit of navigation to get there.
Usually there are 3 reasons for your symptoms
1) running on one cylinder ( leaking head gasket - bad ground cut off wire - valves not opening or closing properly )
2) governor malfunction
3) main jet problem
And if it was a B & S engine then you add leaking inlet manifold to that list
If one exhaust valve was not opening then you would have great compression on the dead cylinder
On top of that these engines have a cranking speed decompressor ( usually ) so cylinder compression numbers are meaningless
kawasaki quote 64 psi to 90 psi at cranking speeds
If a car engine gave those sorts of numbers you would be booking it in for a head gasket or new rings
So take the rocker covers off and check the valve lash & rockers
Cams have the same lift & valves are the same length so each valve should poke out the same amount when closed
 

Tiger Small Engine

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Kawasaki have their service manuals on line as a free download
Should have the parts list there as well but it takes a bit of navigation to get there.
Usually there are 3 reasons for your symptoms
1) running on one cylinder ( leaking head gasket - bad ground cut off wire - valves not opening or closing properly )
2) governor malfunction
3) main jet problem
And if it was a B & S engine then you add leaking inlet manifold to that list
If one exhaust valve was not opening then you would have great compression on the dead cylinder
On top of that these engines have a cranking speed decompressor ( usually ) so cylinder compression numbers are meaningless
kawasaki quote 64 psi to 90 psi at cranking speeds
If a car engine gave those sorts of numbers you would be booking it in for a head gasket or new rings
So take the rocker covers off and check the valve lash & rockers
Cams have the same lift & valves are the same length so each valve should poke out the same amount when closed
Original poster does not have the skills and knowledge to set valve clearance properly, etc.
Simply take it to shop, tell them what you have done, and they should have you up and running soon.
 

slomo

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I will but I just mowed what there was today with my other hustler raptor with the Kohler engine but we are in a severe drought here in Galveston county in Texas so all the San Augustine grass is dying. This raptor (unlike the problem raptor with the Kawasaki) is set at the third lowest setting and just plows through it easily. The Kawi raptor never struggled at the same setting until this year. And it’s not tall at all, I would say 4-5 inches/whatever a normal week growth is. I don’t let it get real high.
You have St. Aug. in Texas, pretty cool. Grass should be low in moisture content if you are in a summer drought. Should be easy to cut.

OR is it a deck issue with the mower in question? Some decks don't cut like others.

I'm guessing on an at times, partially clogged fuel tank. Dump and flush the tank/s out. Blow out with compressed air and safety glasses. Make sure the tank is in as new condition. All new fuel line from the tank/s to the carb. Make sure you have good flow TO the carb into a glass jar or similar.
 
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I have a 2013 Hustler Raptor with a Kawasaki engine that bogs down under load in high grass and I have to slow down to let it recover or it acts like it’s going to die. I’ve had it happen once coming up out of a culvert without mower engaged while pulling a leaf picker upper attachment. The engine runs strong and sounds good but we have:

Replaced:
- Both ignition coils
- Both spark plugs
- Mower blades
- Air filter
- mower belt
- fuel filter
- Fuel solenoid on carburetor
- Had the carburetor disassembled and cleaned.
- Replaced Fuel Evaporation System Filter

At a loss on what to try next. Maybe Spindles or PTO?
 
Joined
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I have a 2013 Hustler Raptor with a Kawasaki engine that bogs down under load in high grass and I have to slow down to let it recover or it acts like it’s going to die. I’ve had it happen once coming up out of a culvert without mower engaged while pulling a leaf picker upper attachment. The engine runs strong and sounds good but we have:

Replaced:
- Both ignition coils
- Both spark plugs
- Mower blades
- Air filter
- mower belt
- fuel filter
- Fuel solenoid on carburetor
- Had the carburetor disassembled and cleaned.
- Replaced Fuel Evaporation System Filter

At a loss on what to try next. Maybe Spindles or PTO?
 
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