Help me with this flipping carburetor!

[1939farmall]

This is the initial start up after getting the tractor back together. I have no doubt I?ve got something wrong. When I crank the tractor with the choke on the throat of the carb just loads up with fuel and runs out. With the choke off I get no fuel. Either way I?m not getting fuel to the cylinders, the plugs are dry as a bone. Anybody know what the fuel and air screws should be set to? The book doesn?t say. Heres what I?ve done on the fuel system: new sediment bowl, new fuel filter, fresh gas, new needle and seat, new float pin, check the float for 1 5/16? travel per the repair book. New gaskets in the carb, cleaned all the port in the carb. What the heck am I missing. Oh and the distributor is froze in place but I figure if I?m not getting fuel there is no point in messing with the ignition yet. Thanks for your ideas!

 

[grizz02]

are you sure there is not a mouse or bee nest in the intake manifold or rag ?

 

[old]

Check your spark any how since if you have fuel dripping that can start a fire/
So make sure you have a good blue white spark at the center wire of the cap and at the plug wires that jump a 1/4 inch gap or more.
#2 pull the carb drain plug and make sure you have a good steady flow of gas that will fill a pint jar in less then 3 minutes and yes catch the gas to look for dirt and water etc.
#3hold you hand over the air intake of the carb and make sure you have a good suction there and you hand gets gas on it

 

[JOCCO]

To add to what Old said is there any chance of air leak on the intake manifold thus not able to take in gas? Also sounds like the float/needle is not shutting off fuel if it is running out the choke end.

 

[showcrop]

Any engine with an updraft carburetor that is cranked more than two revolutions and does not start should have gasoline running out the throat as soon as cranking stops. That is simply gravity at work. Dry plugs means no gas. Check how close to sealing your choke butterfly is in the throat.


Do you really mean one and 15/16 inches of float travel? That is apparently not a carburetor that I am familiar with.


By "froze in place" does that mean that the rotor is not turning or just that you can't adjust the timing?

 

[Steve@Advance]

I'm not seeing carb problems, it's doing just what any updraft will do.

The gas running out is a result of unburned fuel running back down out of the intake following a failed start.

How much did you have apart? Has it been stored for an extended time?

May be low on compression if the rings are dry or the valves are rusty or sticking, or if they were not adjusted if the head was off.

Try a spoon full of oil in each cylinder to raise the compression.

As said, check the spark at each plug. Any chance it's cross wired or out of time?

 

[casecollectorsc]

Load needle open 1 1/2 turns? Couldn't get a tractor started here one time. Nephew shut it off by turning the load needle in to kill it.

 

[1939farmall]

It sat for a long time. Just had the head reworked with new valves and seats. I guess the rings could be dry everything looked good when I had the head off. We did put a new sleeve and rings in cylinder 3. I doubled checked my wires it looks correct.

 

[1939farmall]

The book says one and 5/16 of an inch of travel. The rotor turns fine I
just can?t adjust the timing

 

[1939farmall]

Had the intake off I don?t believe I have a blockage there but I may have to recheck it.

 

[1939farmall]

I think I?m gonna walk away from it for today and look at it with fresh eyes later! I run through theses ideas then. Step by step. Working on something when your aggravated is sometimes a good way to screw it up worse! Thanks old.

 

[1939farmall]

Thank you I?ll set it close to that

 

[1939farmall]

I put new gaskets on the manifold. Maybe I?ll re torque it I put I new needle and seat in I?ll have to recheck the float

 

[David G]

You sure you put the venturi back in?

 

[old]

Yep never good to work on something when your mad it it or you tend to cause more problem then you fix

 

[1939farmall]

LOL! You made me laugh because I?ve done that before! Put the carb all back together and on my super h turned around and there it was on the workbench! I checked, the Venturi is in

 

[old]

One I have done before is to open up the distributor cap and pull the rotor and then leave it sitting on the hood and wonder why it does not start

 

[David G]

Me too, runs like crap.

 

[Steve@Advance]

You did adjust the valves after the head was back on...

 

[1939farmall]

Yes I set them to 17 thousands per the book. Started with number one on TDC the worked through the rest.

 

[1939farmall]

LOL! Yup I?ve pulled that move too!

 

[dzc3]

I would check that you have no air restriction on the air filter side. Old mouse nest and wasp nest can cause a lot of trouble. Also will it run if you put a squirt of gas in each cylinder replace plugs and give it a go

 

[gene bender]

Are you sure you got the tab in the shaft correct cause if you didn't the butterfly will not open and the engine will not start.

 

[David G]

Remember when setting valves each cylinder has two TDC's.

 

[1939farmall]

I double checked that. I pulled the carb off and set it on the bench for the night, I want to go back through it and make sure I have all the ports open so I?ll get a second chance to get the tab In the slot.

 

[1939farmall]

Yeah I need to go over that. Now I?m double thinking that very thing. I may even go ahead and pull the manifold back off and make sure I have no restrictions. I checked it when I pulled it off the tractor during the tear down but it did sit in the shop for awhile.

 

[David G]

If you hold your hand over carburetor when cranking, should suck good on your hand.

 

[1939farmall]

I think I did it right. I brought number one on TDC then made sure the rotor was set to fire on number one cylinder. I went ahead and did the same for each cylinder. I know there are a couple ways to set the valves. If that?s not right please give me the correct procedure and I?ll gladly go over it again.

 

[David G]

If it sucks good, and compression good, should run

Dry plugs indicate it is not sucking in fuel.

 

[1939farmall]

I pulled the carb to double check what I did. Once I put it back on I?ll check that.

 

[Rodney51Cub]

Double check your plug wires are on the correct way. Can not tell for sure from the picture but it appears that the firing order is wrong. Top right on the cap is number 1 then clockwise looking at cap is 3 then 4 then 2. If it is correct forgive and old guy with glasses.

Rodney 8)

 

[Rodney51Cub]

Forgot to say, # 1 cylinder by the fan.

 

[1939farmall]

Crap. I may have it wrong. I?ll have to look at it next time I work on it.
Thank you.

 

[FBH44]

Here's my H carb adjustment procedure, after I reviewed several different manuals.
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.
[Note a new float might already be set correctly.]

INITIAL settings are as follows to get the engine 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 as follows;
Get the engine warmed up, and idling.
Turn OUT the small idle-air-mixture screw until rough running, then turn in until engine idles smooth. (Mine is set at 1 turn open.)
Rev it up, wide open, warmed up, then turn the big 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.)

Engine should rev up smoothly and evenly.
Too Lean = stumble, sputter, damaged melted plugs.
Correct = tan plugs.
Too Rich = back smoke, black sooty plugs.

The other thing is, replace the distributor cap and rotor. If the center electrode is worn too much, she will not start. Use the brass-contact cap, not the cheap aluminum one.

 

[John M]

Unless my eyes are deceiving me, you have the plug wires on wrong.

 

[1939farmall]

I don?t think you eye are wrong at all. I think I got it wrong! Thanks for taking a look

 

[1939farmall]

Great info. Thank you. This is exactly what I needed.

 

[JMOR]

If wires wrong, then by your description of valve adjustment, that may be wrong too.

 

[1939farmall]

That what I?m thinking too. That?s where I?m starting next chance I get
to work on it. Thanks you.

 

[BarnyardEngineering]

I wouldn't get too crazy chasing dry plugs myself. Just because the plugs are dry does not mean you aren't getting fuel. Dry plugs are firing and burning off the fuel. Wet plugs indicate that the engine is flooded and/or not firing.

You can time your engine using the #1 cylinder as either the front or the rear, as long as you time it consistently, counting from rear to front or front to rear. Seen plenty of these old 4-cylinder engines timed off the rear cylinder.