carberator excess fuel found in air intake


To those who have been at IHC tractor mechanical repair for a long while.
Here is the situation; Rebuilt the engine honed sleeves put in over sized {10 thousands over} rings set up timing and all valves to spec.
In cranking over the following result happens: after about 4 to 7 turns of starter and engine the air intake side of the Zenith up draft cab has an amount of ""excess"" fuel coming down the tube / by excess I mean "when I open the drain pet calk under the air intake side of the carb" I can drain off at least a table spoon of fuel [ by the way I use high test since we have ethanol in our lower grades in Canada
// I have also rebuilt the carb in the process of rebuilding the rest of the tractor// I HAVE re inspected the carb and discovered that the out side of the carb is clean and level ""YET"" the internal section between the two parts of the carb, I HAVE / using a machinists straight edge/ is fractionally lower /seen enough to let light through/
SO WHAT DO I DO TO CORRECT OR STOP THE EXCESS FUEL>> By the way this tractor sat in parts for over 20 years and, in rebuilding I discovered that the carb had been submerged in water a some time in storage container it was in; found no cracks in wall yet as said above, the carb appears to have warped.
Any one ever have the similar or the same happening as mine? Any help would be helpful since as yet I haven't been able to get the engine to fire because it seem to be getting excess fuel ( even put fuel in the plug holes to encourage starting no luck ) flooding happened.
SO where do I start to rework the carb?
PLEASE HELP
Thank you Wm.
 
You have a couple of possible problems.

The warped cover, that is likely a result of the screws being tightened with the venturi not fully seated, or assembled wrong. The cover should sit flat against the bowl when everything is right. If it is not severely warped, you can try to file it flat. Not easy as the float hinge will be in the way, but give it a try, or try to find a better carb to work with. The surfaces do need to seal, especially in the center as that is where the idle fuel is drawn up.

Next, to determine if it is flooding, take the air filter tube off, turn the fuel valve on, let it sit for a few minutes and see if gas starts dripping. If it does, the float is set too high, the float is partially sunk, there is trash in the needle valve, or the needle valve is damaged.

If there is no dripping of gas while just sitting, but does drip after a failed choke assist start, that is normal. There is likely another problem, as in ignition or spark timing.
 
Steve;
Here is what I have gone through this morning;
Lapped both parts of the carb housing / still a minute amount of light can be seen under the straight edge
blew out all ports
made a slightly thicker gasket .002 thicker than original
recheck all"" mechanical"" settings from top dead centre [ when I reassembled the engine / knotted and read & reread several times my mechanics Manuel then checked and rechecked marks on timing gears before installing timing cover/ then marked with punch marks the timing cover and front pully and also marked them with black marker]
checked TDC #1 and the distributer #1 then went on to check #3,4,2 in the same manner
installed carb.
turned over with starter AND NO CHOCK ON
>>>>>> result the same as before fuel came out of the air intake where the air filter should have been {not on at this point of trial}
also noted a strong suction when I placed the fleshy part of my hand over the intake of the carb.
>>>>>>>>Still perplexed<<<<<<<< guess I may have to pick up the carb my friend has for me at Thedford Ont. and hour from me.
followed all you wrote seems to be what I did
lets hope d different carb does the trick. I shall keep you up dated as I go on in the next week.
Wm.
 
When you timed the distributor at TDC, did you bring the piston up on compression stroke? If not, the distributor could be 180* out.

Even if the carb is not perfect, it should at least try to start. Don't give up on it just yet.

That you got good cranking vacuum is a good sign the internals of the engine are right.
 
top dead center #1 checked and re checked before I even put on the timing cover Back and forth between Manuel and the set of marks on the timing gears then marked the timing housing at the oil seal and the front pully purposely making certain cautiously certain all was in the correct place [because I have seen what can happen when the timing is ""OUT"" a valve through the piston! also checked the timing of #1 on TDC and the position of the #1 position on the distributer ;Then I have visual check on the #1 piston and the intake and exhaust valves >> at top sea center both have the apropriate "back lash" gap>> so I know that the cylinder is in pressure position for compression the distributer is in position to fire and valves are properly closed. >>> I have done this at least 3 times ""BECAUSE"" I had the same uneasy thoughts DID I mis time the system or mis something. I followed the same procedure along the line for 3,4 &2 "" JUST TO BE CAUTIOUS>""
^^^ Something I have Missed??? the only thing When I gathered up the parts to strat working on the rebuild I noticed that the container that the carb was in """had """ at some time become partly filled with water ^^^ the carb was in it^^^ the choke butterfly was damaged^^ so I hunted and found a NEW OLD STOCK one in Ohio near the Pen boarder. The carb had slush in it and obviously when I opened it, it had had water in it BECAUSE of the crud in the bowel. NO cracks in the casting that I can see just the un level ness between the out side and the inner web where the jet is.
MY suspition fuel is leaking past even after my lapping earlier today. Other than That ????
thank you for your insights / this Friday I will be picking up the other carb from my friend at Thedford Ont. One hour from me.
Wm. from near London Ont.
 
You need to pull a plug wire and check for spark. Hold close to a ground and see if it has a blue spark that will jump a gap of 1/4 to 3/8 inch. No spark or weak spark will cause a problem such as you are describing.
 

You don't have an excess fuel problem. Most of these old tractors have updraft carburetors as do my old Fords. If I have one that doesn't fire right up, I will pull the intake to make sure that I have gas. If I don't see at least a tablespoon worth, I know that I have a lack of gas problem. What happens is that the pistons suction is drawing the fuel up through the carburetor, manifold and into the cylinders. If the engine does not start, as soon as you release the start button. All of the gas that is in the manifold is not going into the motor, gravity is pulling it back down. This is a common non-problem and comes up regularly here. Check you plugs and evaluate your fuel situation at the cylinders where the fuel needs to get, to instead of where gravity brings it back to.
 
Dear showcrop;
What I have is new NGK plugs, wires, & distributer parts and I have also, using an ohm volt meter continuity between the plug bace in the head and the ground post of the battery [posative ground] and a sharp blue spark when I take a plug out and ground it to a grounding point. It took my a while to achieve this since painting each piece separately caused an insulating effect and so I ran a 10 G grounding wire in the wiring harness to insuer each item had continuous ground ; lights and all other electrical components [disributer, engine block, generator.]
Some times I wish I had someone close to go over this tractor with me step by step for I still have the uneasy feeling I have missed something small but critical / yet can't see what// ouch! This is the time I wish my father was still alive and capable since It was his tractor and he had also worked for an IHC dealer near Sarnia Ont. in the 50s and we lived on the home farm until the middle 60s,in the same area where we had lived. I live near London Ont. now.
Wm.
 

Well, 1946, it appears that you have your bases pretty well covered. Here is another check for your ignition system. Try giving it a little sniff of ether. If it fires on the ether you know that you have ignition, and that you are close on timing. If no fire on the ether, you have an ignition or timing problem.
 
There is an other problem that has been located that I now know is the cause of at least part of the cause of the problem. Two valves are
not holding in the system. Hadn't even considered this as a possibility until an acquaintance of mine suggested check cylinder pressure
using my thumb on each plug hole. So here goes Pull the head and inspect.
Wm.
 
(quoted from post at 05:24:51 11/16/17) There is an other problem that has been located that I now know is the cause of at least part of the cause of the problem. Two valves are
not holding in the system. Hadn't even considered this as a possibility until an acquaintance of mine suggested check cylinder pressure
using my thumb on each plug hole. So here goes Pull the head and inspect.
Wm.

Before you pull the head go over your valve lash adjustments. I had one once that was not closing after a rebuild and caused poor running.
 
Back lash is in proper adj. I can even move the rockers a slight amount on all tappets. .014 or what ever the book calls for I don't have it
here right now but did all the adjs according to hoil then double checked after I have hand cranked over 3 or 4 times even before putting
the key on just to make certain that all the rods were seated on the cam shaft then rechecked
Thank you for the reminder though. Good to have someone else's input because just one item missed could create a disaster.AS I AM
finding out
Thank you again for the reminder.
Wm.
 

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