Carb Throttle shaft play (What is concidered ok?)

[AJ85WA]

Hi Guys

What is concidered an ok amount of throttle shaft play?

Mine is similar to this video
https://www.youtube.com/watch?v=kETWfG9k8Vc

Reason im asking is because i have some play in the shaft and when i turn the fuel pump on and pump the throttle i will get some fuel leaking out of both ends of the throttle shaft ( now I know that pumping the throttle squirts fuel into the neck and fuel willl run down the walls back into the air box)

But I just want to confirm if this is concidered normal as I have seen some stains on the top of my airbox indicating a fuel leak from this exact area over the last 150hrs and I have tightened all carb 2 bowl bolts, new gasket, and acc pump seals are good.



You can see the wet fuel on both sides of the throttle shaft in the below picture after pumping the throttle twice.

[rvbuilder2002]

I consider a small amount of detectable movement acceptable.
The amount shown in the video is much more than detectable movement, and in my opinion warrants bushing replacement.
This level of clearance can begin to have enough of an induction leak that it can cause a slightly lean condition.

[lr172]

Originally Posted by rvbuilder2002

I consider a small amount of detectable movement acceptable.
The amount shown in the video is much more than detectable movement, and in my opinion warrants bushing replacement.
This level of clearance can begin to have enough of an induction leak that it can cause a slightly lean condition.

+1

Once meaningfull wear is present, the wear tends to accelerate. As Scott mentioned, the air leak will reduce the negative pressure in the venturi and cause the carb to think there is less airflow than there is and deliver less fuel than required. It is possible that at some point, even with full rich mixture, you will be delivering an insufficient fuel flow to the engine, resulting in a lean mixture. Going lean at high MAP / high RPM regions can cause detonation problems.

They make replacement bushing for exactly this reason. It is not an easy job, but not overly difficult with the right tools. You typically need some type of jig to hold the drills and reamers in line and parallel.

Larry

[AJ85WA]

Thanks Guys

Appriciate the feedback.

I will order the bushes and get working on this very soon.