I need help

[torreybutterfield3]

I have a kohler magnum 18 engine on my exmark walk behind what is baffeling me is that im only getting gas to one cylinder my plugs are firing the carb is getting gas the valves are opening and closing but im getting gas to only one cylinder? Im stuck and need help

 

[SeniorCitizen]

I have a kohler magnum 18 engine on my exmark walk behind what is baffeling me is that im only getting gas to one cylinder my plugs are firing the carb is getting gas the valves are opening and closing but im getting gas to only one cylinder? Im stuck and need help

Using a flammable substance such as carburetor cleaner squirt a short shot on the gasket area of the intake manifold of that dead cylinder with the engine running at low idle speed. If there is a leak there it will draw the combustible in and the cylinder will temporarily fire and you'll know what the problem is . That's only one test but is the least expensive for a beginning .

 

[EngineMan]

In your list I didn't see a compression test on that cylinder..!

 

[chance123]

In your list I didn't see a compression test on that cylinder..!

Exactly! The same intake manifold feeds "both" cylinders fuel/air, so my guess is a valve or even hopefully not, a bad cam, broken pushrod, con rod, etc.

 

[SeniorCitizen]

Exactly! The same intake manifold feeds "both" cylinders fuel/air, so my guess is a valve or even hopefully not, a bad cam, broken pushrod, con rod, etc.

I once had a 240 six cylinder ford pick up like that but each of the six cylinders had their own manifold connection at the head. When cylinder #3 gasket went bad it sucked air and that cyl. didn't fire. Actually there wasn't a gasket there from the factory on any of the 6 cylinders. Manufactured that way. Because of warping Ford got to sell everyone a gasket set at overhaul time.

A small block 400 chevy will drop 2 cylinders across from each other if the correct vacuum hose ( the one that bends 180ｰ ) cracks.

 

[chance123]

I once had a 240 six cylinder ford pick up like that but each of the six cylinders had their own manifold connection at the head. When cylinder #3 gasket went bad it sucked air and that cyl. didn't fire. Actually there wasn't a gasket there from the factory on any of the 6 cylinders. Manufactured that way. Because of warping Ford got to sell everyone a gasket set at overhaul time.

A small block 400 chevy will drop 2 cylinders across from each other if the correct vacuum hose ( the one that bends 180ｰ ) cracks.

What you say is true, but with only 2 cylinders that share the "same" intake manifold, an air leak in one will also affect the other. The engine will be ingesting air/fuel through the path of least resistance. Regardless, even with a leak, "some" of that air/fuel mixture should make its way into that failing cylinder resulting in some sort of combustion. A compression test will give you a lot of information. Another thing to remember is that your spark plugs will tell you the health of your engine. After running your engine on the one good cylinder, then immeadiately check that spark plug. If that failing cylinder's spark is "wet", your problem is "not" fuel delivery. If it is dry, I suspect an intake valve problem.