Kohler CH730 loss of power

zmcg1995 · Aug 14, 2018

I have a 2005 Exmark Lazer Z 60" with a 25 Kohler. I have been chasing a loss of power issue for the past couple weeks.

Compression is 130-135 on each cylinder
Replaced all fuel lines, filter, and pump
Replaced air filter
Plugs are clean
Cleaned carb
Replaced intake and exhaust manifold gaskets
All pulleys are rotating fine

Mower idles and throttles up fine but once you put any load on it, it bogs down.

Any thoughts or help would be greatly appreciated.

solefate · Aug 14, 2018

zmcg1995 said:
I have a 2005 Exmark Lazer Z 60" with a 25 Kohler. I have been chasing a loss of power issue for the past couple weeks.

Compression is 130-135 on each cylinder
Replaced all fuel lines, filter, and pump
Replaced air filter
Plugs are clean
Cleaned carb
Replaced intake and exhaust manifold gaskets
All pulleys are rotating fine

Mower idles and throttles up fine but once you put any load on it, it bogs down.

Any thoughts or help would be greatly appreciated.

Have you checked to make sure you're actually firing on both cylinders? Also are you losing/burning any oil?

zmcg1995 · Aug 14, 2018

solefate said:
Have you checked to make sure you're actually firing on both cylinders? Also are you losing/burning any oil?

Yes I am running on both cylinders and I have some small oil leaks but nothing major.

Rivets · Aug 14, 2018

Have you checked to see if both cylinders are firing and carrying their part of the load. You may be running on one cylinder. If you have a good pair of insulated pliers, run the engine at 1/2 throttle and while it is running pull the spark plug wire off, one cylinder at a time. Engine should loose speed when you plug the plug and regain speed when you push it back on. If nothing changes when you pull the plug wire, that cylinder is causing your problem and you’ll have to figure out what’s wrong.

zmcg1995 · Aug 14, 2018

I have done that and it lowers to the same speed when I unplug each cylinder.
So it is indeed running on both.

solefate · Aug 14, 2018

zmcg1995 said:
I have done that and it lowers to the same speed when I unplug each cylinder.
So it is indeed running on both.

Any oil leaking from head gasket? Or excess gas coming out or burning off in the muffler?

Rivets · Aug 14, 2018

Does the governor kick in under load? Does the engine spit and sputter under load? Does the engine or blade speed bog down?

zmcg1995 · Aug 14, 2018

solefate said:
Any oil leaking from head gasket? Or excess gas coming out or burning off in the muffler?

No oil leaks from head gasket. I had an oil leak from the head gasket and I fixed that and that actually seemed to be when the issue started. I believe if I had a blown head gasket I would lose compression in that cylinder.

mhavanti · Aug 14, 2018

Remove the muffler or at least loosen the exhaust flange bolts. Run it up to see if it continues to pull properly. If so, your muffler is being restricted by a collapse inside. Doesn't happen often in the mower world. However, it does happen.

zmcg1995 · Aug 14, 2018

Rivets said:
Does the governor kick in under load? Does the engine spit and sputter under load? Does the engine or blade speed bog down?

It doesn't seem like it does. That seems like that is what is missing. It doesn't spit or sputter but it just bogs down. The engine and blade speed bogs down.

Kohler CH730 loss of power

More options

zmcg1995

Forum Newbie

solefate

Active Member

zmcg1995

Forum Newbie

Rivets

Lawn Royalty

zmcg1995

Forum Newbie

solefate

Active Member

Rivets

Lawn Royalty

zmcg1995

Forum Newbie

mhavanti

Well-Known Member

zmcg1995

Forum Newbie

Footer Links 1

Footer Links 2