ZG127S Hard starting when cold.

[Richnmo]

I checked the fuel outlet at the tank and no restrictions or debre. But during initial startup cranks ok but no fuel like its lost its prime. It will crank for 20 to 30 seconds with choke on and nothing. Pull air filter and fog it with carb cleaner and fires right up. Once its warmed up it fires up every time. But wait a week and same thing all over. My neighbor replaced the fuel pump last year and said it made no difference. Any help would be great, other wise I'll be taking my Big Dog over to knock it out ! Thanks guys

 

[JasonW]

It was said in your other post but check the choke linkage to make sure it’s actually closing.

 

[whitetiger]

Spray carburetor cleaner around the intake manifold while the engine is running. I suspect the engine will rev up, meaning you probably have a failed manifold-to-cylinder head gasket.

 

[Richnmo]

It was said in your other post but check the choke linkage to make sure it’s actually closing.

Thanks Jason and I will check that the next time he's ready to mow. But when engaging the throttle you can feel the detent once you move it to the choke mode. But I will manually look at it.

 

[Richnmo]

Spray carburetor cleaner around the intake manifold while the engine is running. I suspect the engine will rev up, meaning you probably have a failed manifold-to-cylinder head gasket.

Thanks Whitetiger but if it had a intake leaking wouldn't he have a drive ability problem or a lean miss? Just saying as it runs out fine just lie it has lost it's prime when he cranks it cold. And he put a new fuel pump on it last year.

 

[JasonW]

Thanks Jason and I will check that the next time he's ready to mow. But when engaging the throttle you can feel the detent once you move it to the choke mode. But I will manually look at it.

I believe the detent is in the throttle handle itself?

 

[whitetiger]

Thanks Whitetiger but if it had a intake leaking wouldn't he have a drive ability problem or a lean miss? Just saying as it runs out fine just lie it has lost it's prime when he cranks it cold. And he put a new fuel pump on it last year.

Not necessarily; as the engine warms up, the intake can seal due to expansion.
It's rare, but it happens.

The first check should be to visually see that the choke butterfly is fully blocking the intake, though.