3000 not running right

[Awlknottedup]

My 3000 started misbehaving recently. It starts right up but will not run unless the choke it out about 3/4. At first I thought it might be water in the fuel, it rained hard last week and the cover blew off. I looked at the sediment bowel but did not see water. I drained it anyway and also the carb bowel, it did not help. I even checked the points. The next day I pulled the sediment bowel and turned the engine over, a good stream of fuel came out indicating to me the fuel pump is ok. I cracked the line at the tank shut off valve and let some fuel drain. This time it started running almost like normal so back to using the box blade. It still needed a little choke to run right. Then I hit a bump and it started running crapy again.

It is a 1965 3000, SOS, with the Holley carb. It has been running fine, swinging a 5 ft brush hog in heavy wet grass in 4th, and pulling stumps. It treats a 4 ft box blade in heavy wet clay almost as if it were not there.

I have my suspicions but looking for comments from the group.

 

[Dave_from_Texas]

Dirty Carb is my guess. The bump stired up more particals and it plugged again. Choke usually indicates that it is not an electrical problem. Soak the carb and clean all of the passages.

 

[Dave_from_Texas]

Also may want to look for a air leak. Manifold, gasket, carb shaft, etc. are suspect.

 

[Dean]

AKU:

The symptoms that you describe are most likely caused by a lean mixture but it is always good practice to verify that the ignition is SPOT ON before addressing carburetor issues.

The Holley carburetor has a vacuum operated accelerator pump operating in the die cast housing. Dirt can cause the piston to stick and/or score the casting. If your ignition system is spot on, the fuel and all screens are clean and your engine stumbles as the governor increases throttle opening, this could be your problem.

The Holley carburetor is sensitive to float adjustment because of the accelerator pump. The steel float pivot pin is secured in holes in the die cast float bowl. Due to the vibration of the three cylinder engine it is not uncommon for the steel pin to wear the die cast housing such that the pivot pin holes become egg-shaped rendering proper float level adjustment impossible. Post back if this is your problem as this can be reliably repaired without replacing the carburetor or float bowl.

Dean

 

[Old Ford Mechanic]

Choke to run= dirt in carb.

 

[Jerry/MT]

Needing the choke to run can be caused by a poorly adjusted carb, a weak spark, or an air leak around the carb metering system.

Make sure you have your carb adjusted properly.

Check the spark at the high tension lead that comes from the coil to the center of the distributor cap. Pull it off at the distributor cap, hold it near a good ground and try a start. If you get a FAT, BLUISH-WHITE SPARK , the color of lightning than your ignition system is OK.

Air can leak around the carb metering section via a worn throttle shaft or seals, a leaking gasket at the carb to intake manual interface, from rust holes or cracks in the intake manifold or from an intake manifold gasket leak. To check that, CAREFULLY spray starter fluid or carb cleaner around these areas with the engine running(BE CAREFUL, this stuff is flamable). You hear the rpm change when you hit the leak.

 

[Awlknottedup]

I sprayed all around the carb with carb cleaner with no affect. I checked the point setting but did not check the timing.

My thought is that the tank valve is getting clogged with sediment at the bottom of the tank. I plan to drain the tank and clean the screen.

If none of that helps I will be taking apart the Holley.

 

[Jerry/MT]

Did you check the carb to manifold connection, the manifold itself and the manifold gasket area? They are all potential air leak locations.