1940 Farmall H Carb Problems

I will start with saying i have one hell of a pieced together machine. It is a Cletract AG-6 that has had the engine from a Farmall H pieced onto it and a loader from god knows where. I bought it at an auction for basically the price of scrap so cant really go wrong there. It runs very well to be honest but as the Farmall H motor is undersized for that machine already i need all the ponies i can get out of it.

So heres the problem, I was attempting to tune the carb the other day after i had torn it apart and cleaned it out. First off there is saposed to be a fuel air mix screw on the bottom left of the carb. If i adjust that screw at all it just leaks fuel and it seems that its only purpose is to hold the main jet in place. Secondly you are saposed to be able to adjust the main fuel adjustments and get the engine to "blubber" i cannot do that at max rpms, in fact i cannot even get it to smoke black when under heavy load. I can open the main screw all i want and it doesn"t make a bit of difference, it will however if i close it a certain amount start starving out. As it is a gravity feed tank is it possible that the tank from the cletract is just not high enough to flow enough fuel to the carb? I am by no means a expert on tractors or carbs so any help is appreciated.

The last issue is the timing. The pulley seems to be way off because if you use a light and match the marks ups to the timing point on the block it runs rough and with absolutely no power. However if you turn the distributor counter clockwise a ways it runs pretty darn good. My question is how to you tune the timing by ear on these things or do you just guess and check how much power you have until you get the best setting?
 
Packing goes behind the lock nut on the main load screw. Depending on the carburetor it won't give anymore fuel than was required with the screw full open. Or you may still have another problem with, blockage the jets or air leaks.
Unless the distributor springs are ideal and you can get the engine to idle really slow a timing light won't be successful. Set the static time with the engine stopped. Then see if the time advances when the rpms go up with the light.
 
(quoted from post at 07:21:25 07/28/14) I will start with saying i have one hell of a pieced together machine. It is a Cletract AG-6 that has had the engine from a Farmall H pieced onto it and a loader from god knows where. I bought it at an auction for basically the price of scrap so cant really go wrong there. It runs very well to be honest but as the Farmall H motor is undersized for that machine already i need all the ponies i can get out of it.

So heres the problem, I was attempting to tune the carb the other day after i had torn it apart and cleaned it out. First off there is saposed to be a fuel air mix screw on the bottom left of the carb. If i adjust that screw at all it just leaks fuel and it seems that its only purpose is to hold the main jet in place. Secondly you are saposed to be able to adjust the main fuel adjustments and get the engine to "blubber" i cannot do that at max rpms, in fact i cannot even get it to smoke black when under heavy load. I can open the main screw all i want and it doesn"t make a bit of difference, it will however if i close it a certain amount start starving out. As it is a gravity feed tank is it possible that the tank from the cletract is just not high enough to flow enough fuel to the carb? I am by no means a expert on tractors or carbs so any help is appreciated.

The last issue is the timing. The pulley seems to be way off because if you use a light and match the marks ups to the timing point on the block it runs rough and with absolutely no power. However if you turn the distributor counter clockwise a ways it runs pretty darn good. My question is how to you tune the timing by ear on these things or do you just guess and check how much power you have until you get the best setting?

The screw on the bottom left of the carburetor is the DRAIN PLUG. Yes, it will leak fuel if you loosen it. Sounds like you need to get your hands on a few repair manuals and study them.
 
There is a fuel bowl drain this screw in question is to the left of that. Althoguh the screw does seems to be something to facilitate cleaning of the main jet.

I did notice the packing beind the lock nut but it seemed to be paper someone had shoved in there so i removed it and replaced it with a rubber o ring. it is possible this is my problem but i dont see how.
 
to time the engine you need a test light. bring the engine up on the number 1 compression stroke and align the timing marks to tdc, remove the distributor cap and the rotor should be pointing to number one plug wire on the cap. remove the lead from distributor to coil. hook a test lamp up to that lead and connect the other end of the test light to the battery hot. loosen the distributor and rotate the distributor to the point at the light just goes out. that will be timed at tdc. the advance is mechanical so when the engine starts it goes advanced with increased rpm. off hand i guess its around 22 degrees or so full advanced.
 
(quoted from post at 07:52:27 07/28/14) There is a fuel bowl drain this screw in question is to the left of that. Althoguh the screw does seems to be something to facilitate cleaning of the main jet.

I did notice the packing beind the lock nut but it seemed to be paper someone had shoved in there so i removed it and replaced it with a rubber o ring. it is possible this is my problem but i dont see how.

A rubber O ring will NOT work. A GOOD carb repair kit will have the new packing included.

Are you 100% certain the engine is from a Farmall H? An H carburetor has only the fuel drain on the left side, and the load metering adjustment screw, which is also on the bottom, but points towards the rear, at a downward angle. The other "screw", to the left of the drain plug, is NOT a screw. It is the clamp nut for the main metering stem. It is NOT an adjustment. It will leak fuel if it is loose, and it CANNOT be tightened from outside the carb. The clamp nut is meant to be held in place, while the main metering stem INSIDE the carb is tightened. There IS a gasket under the clamp nut, as well as under the hex head of the metering stem. DO NOT mess up that clamp nut. It is no longer available, anywhere, at any price.
 
First is to ID your carb by the numbers & letters on the tag. If no tag send us a picture. We will be able to help you.
 
This is from the only tag i could find on the engine towards the rear.

Model:H
Serial No: FBH-209422 X1
Internation Harvester
1815 Max rpms

As i stated earlier this thing is pieced together from apparently anything they could find. Nothing would surprise me.
 

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