H dies when throttling up

I am having problems getting my H to throttle up when moving to WOT. The RPMs slow and it dies. I've had it for about 3 years and it ran great until last fall when it just died while driving. Since then I have replaced the manifold, changed the points and condensor, replaced the plugs and wires, rebuilt the carb, and replaced the governor with a used one since the bearings were shot in the other one. I also static timed it to the 1st mark on pulley by loosening the distributor and turning it until I get a spark and then re-tighten it. With all those changes it still does the same thing. It's frustrating and I am not sure what I should be looking at next. It starts fine and I can get it to idle ok by adjusting the carb but when I pull back the throttle it doesn't even want to rev up before it dies. I know the governor is linked up to the carb correctly and I have adjusted the linkage according to the manual. Hopefully someone here has experienced this same problem and can tell me what my next step should be. Thanks.

sounds like a fuel flow problem to me. Disconnect the line to the carb and let it run into a container...the flow should be heavy and constant,let it flow for a long time..if the flow slows you have a clog in the inlet in the tank,the tank may need to be cleaned out.

You might not need this, but it might help. My "H" carb adjusting procedure;

Make sure the float isn’t sticking or touching the insides of the float chamber. Some previous advice was to use a Dremel tool and smooth the insides of the float chamber so the float doesn’t rub or touch. Pretty important.
Set the float so the top of it rests 1 27/32" above the flat surface of the float chamber.
Initial settings are as follows to get it started;
Main fuel adjusting screw, big screw facing down at an angle, towards the rear, at the bottom of the carb; 2 1/2 to 3 turns open. This main screw turns clock-wise for leaner mixture. [This screw adjusts fuel.]
Idle air-mixture screw, smaller screw facing forwards, on upper left-hand side of carb; 1 to 1 1/2 turns open. This idle screw turns counter-clockwise for leaner. [This screw adjusts air.]
Idle speed screw, faces outboard, at the top of the carb; set for 450 rpm, and make sure the governor correctly engages in the slot. [This screw adjusts RPM’s.]
Final settings are determined as follows;
Get the engine warmed up, and idling.
Turn OUT the idle air-mixture screw until rough running, then turn in until it idles smooth. (Mine is set at 1 turn open.)
Rev it up, wide open, warmed up, then turn the main fuel adjusting screw IN until rough, then out til smooth, then 1/4 turn to 1/2 turn further out. (Mine is set at 1 turn open. Other advice has been to set it at 2 1/2 turns open for pulling implements.)
Should rev up smoothly and evenly.
Too Lean = stumble, sputter, damaged melted plugs.
Correct = tan plugs.
Too Rich = back smoke, black sooty plugs.

Coil.

Allan

I am diagnosing it as a carb fault.
If there is a particle of dirt in the main jet it will act as described. I like a properly adjusted mixture, and FBH44 has a good procedure for that but it must be clean to allow fuel to make it to the combustion chamber. Also assure it is flowing to the carb, the screen in the carb inlet is a little known spot for grief. Jim

Your fuel bowl screen may be plugged. Turn off the gas and remove the glass bowl. then turn on the gas, you should get a nice stream from 2 sides.

Randy

Try opening the main jet adjusting screw near the bottom of the carburetor as this will enrich the fuel mixture. Hal

I agree with the others, most likely fuel issue.

Thanks for input. I will be looking at all your suggestions, starting with the fuel issue. I plan on taking my carb apart again and seeing if there are any ports clogged up to begin with.

Finally found my problem. When I rebuilt my carb I put in all the new parts that came with the kit and one of the parts was the throttle stop screw. Turns out that this new screw was almost a quarter inch longer than the old one so when I screwed it out 1 1/2 turns per the adjustment instructions it would still keep the butterfly in the carb open too much. I didn't want to keep screwing it out further because then the spring wouldn't engage on the screw head to keep it tight. I cut off part of the new screw to make it the same length as the old one and now I can get it to idle at low throttle and it speeds up when moving the throttle handle to WOT. Something as simple as that caused me a lot of headaches. Thanks for all the advice.