Poor Idle

[Banger]

Hello all,

I am a new member having recently acquired a 1985 FJ73. I am quite enjoying it so far, and it appears to have been well looked after.

However, it has a small idle issue I would like to have sorted. The problem is that when reducing power (taking foot of throttle), the idle does not return properly to a nice even setting. It tends to sit up too high - it is not closing properly or fully. A flick of the throttle helps, but is not ideal.

Looking at the carby I see just one fairly light spring on the forward side which closes the throttle. I suspect there should be a heavier one (spring) on the rear side near the throttle cable, but am not sure. Can anyone shed some light on to what the closing spring setup should look like?

Thanks all in advance.

Tim

 

[crushers]

or you can have a faulty carb leaking a small amount of fuel into the passage keeping the idle a bit high...

 

[Entaran]

3F or 2F motor?

 

[Banger]

Sorry for the lack of engine type info, it is a 3F.

I do not think it is leaking air, because when I fiddle with the carby, it will return to a proper idle if it closes all the way. The problem is getting the carby to close properly. My fix will be to put a heavier spring on it, but I wanted to check my setup against a factory proper one first if I could, hence the posting.

Thanks

Tim

 

[crushers]

hummm, if you are concidering a heavier spring then there is bindage happening so find the bindage before you get wear in the linkage or in the shafts...

 

[Banger]

Thanks Wayne, a good point, I will look for the binding.

Can anyone confirm that there is just the one closing spring typically on a 3F carby butterfly?

Thanks

 

[roscoFJ73]

Here some pics of the carb on my old 3F .I think there was at least 3 maybe 4 springs on the carb

 

[roscoFJ73]

Thanks Wayne, a good point, I will look for the binding.

Can anyone confirm that there is just the one closing spring typically on a 3F carby butterfly?

Thanks

I would have thought 2.

 

[Banger]

Thanks Rosco,

actually my carb looks a lot like yours so I guess it is standard. Only one of those springs is the actual closing spring I think. Thanks.

PS. Are you in Perth as well?

 

[thePunter1]

Hey - I have this exact same problem. Fast idle fixed by heavy tap on the go pedal.

I would be interested to know if anybody identified the problem area and more importantly how they fixed it.

Regards,
David.

 

[roscoFJ73]

Hey - I have this exact same problem. Fast idle fixed by heavy tap on the go pedal.

I would be interested to know if anybody identified the problem area and more importantly how they fixed it.

Regards,
David.

You need a new spring under the pedal. My 73 was doing the same thing . Over time the spring loses just a little tension and does not bring the pedal back to where it should be.
You cant really tell by looking at the spring

 

[roscoFJ73]

Thanks Rosco,

actually my carb looks a lot like yours so I guess it is standard. Only one of those springs is the actual closing spring I think. Thanks.

PS. Are you in Perth as well?

Yep ,NOR

 

[thePunter1]

Thanks Rosco.