FJ40 stalls when stopping (1 Viewer)

[4mydogs]

My '69 FJ40 - original engine and carb - stalls when braking to a stop. The carb has been apart and cleaned, and has a new float. It idles great, and drives like a champ. If you stop very gently the engine will continue to run, but anything more than a gentle stop means that once you push the clutch in it dies. Is it time for a new carb kit, or is there something else at play here?

Thanks.

 

[John Smith]

Do you have a vacuum brake booster on this truck or the non boost setup?

 

[4mydogs]

I have no idea. How can I tell?

 

[bikersmurf]

Does your brake master cylinder bolt directly to the firewall or to a vacuum booster (round pot) which is attached to the intake manifold?

 

[4mydogs]

No vacuum brake boost.

 

[mruff]

Sounds like it runs out of fuel when you hard brake. I.m no expert but where is the fuel level on your carb glass?

 

[4mydogs]

Fuel level is right about midway. I've adjusted the float to make the level higher and lower, but it doesn't make any difference. It still stalls. Turn the key and it starts right back up.

 

[4mydogs]

Any other ideas...?

 

[Pin_Head]

I have no idea. How can I tell?

Any other ideas...?

You might be in over your head and it might be time to find a mechanic with experience with FJ40s.

 

[nohuri]

Have you checked your idle solenoid?

 

[DougAustinTx]

Primary butterflies are being pulled tighter into their seats due to engine rpm. Set your idle stop screw slightly deeper to prevent the butterflies from snapping shut too hard when vacuum is high.

 

[4mydogs]

Thanks for the ideas. If I ever get my head gasket installed I'll get back to the carb issues...