IH 464 can't keep running.

We've been battling with a IH gas 464 for over a year now.

When you start it you have to full choke it. Then as soon as you start throttling it up it dies.

When we first had issues with it not running, wouldn't start. We had the carb overhauled and put in a new one of those electronic shutoffs that keep it from dieseling.

Mounted it and could get it to idle, but would die at higher rpms. Then it seemed things went downhill from there for a while. Couldn't even get it started.

We put in new points, condensor, plugs, fuel pump, cleaned the carb up some more. It would fire and run then die. Almost any throttle would cause it to die. Still had to have it at full choke.

Our local Tractor implement has had it for 3 weeks now. They put new cap and rotor on it. Still needed to full choke it to get it going but they could get it to keep running if they inched the throttle up while steadily decreasing the choke. Never would run smooth.

They brought it back hoping some work with a load on it plowing snow wood get it good an warm and straighten it out. It died right after I got the 3 point blade hooked to it and wouldn't start.

It kind of acts like it runs out of fuel, but then floods and won't start. I know, 2 extremes, probably not likely. Some mechanics I talked to said it sounds like an air leak. However, the implement said they checked for that.

We're at a loss, the tractor is back at the implement. Would like to point them in the right direction as nobody is making any real progress.

Hi, if it was a Diesel model the first thing I would do is take the fuel lines out of the bottom of the fuel tank and drain all the gas and junk out of the tank. Blow compressed air through the fuel lines. Also try loosening the fuel tank cap just incase the air inlet is clogged. My brother had the remains of a dead lady bug in the fuel tank of his 684 Diesel that had similar symptons. The 684 has same fuel tank system as 464.

JimB

Recheck the intake manifold vacuum leak, they can be internal to the exhaust system! Best guess not yet checked! Jim

Hold your hand over the throat of the carburetor and see if there's good suction on your hand. If there's not much suction your manifold vacuum
is too low to suck that fuel into the engine. Could be a leaking intake manifold or worn rings & cylinders. Do a compression test and compare the readings.

If there's good suction on your hand you need to check the gas flow from the tank to the carburetor. Unhook the gas line at the carb and see if there's a full stream of gas from the tank. Catch the gas in a clean container. If there's good flow there remove the tube fitting where your gas line connects and look for a screen. If you have a inline gas filter I would remove it if its not for a gravity flow system.

Make sure your intake manifold isn't leaking. Spray some starter fluid where the manifold is connected to the engine. Do this while cranking the engine and see if the engine fires. Hal

We removed the screen off the tube fitting. It does get good gas flow.

The suction on the throat of the carb is also really good.

Thanks for the replies.

I think the problem is in your carburetor. I would take off that antitdieseling shutoff to see if its restricting the fuel to the carb. If that doesn't help I would disassemble that carburetor and see if the main jet is plugged. With your hand over the throat of the carb that engine should start when trying to make a start.
That's how we checked older cars and trucks that had mechanical fuel pumps. The engine would start and run as long as held your hand over the throat of the carb. Hal

The implement removed the shutoff and put in a plug with the regular adjustment in it and it didn't make any difference. They also took off the carb and cleaned it. They said it wasn't dirty which is expected as we cleaned it several times trying to hopefully get something to come lose that we missed the time before. The mechanic even used a thin wire to go through the main jet and said it was clean.

They also replaced the shutoff with a new one to make sure.

The mechanic seems to also think the carb is the problem and wants to put a new $400 one on it. I just don't see what can be wrong with this simple carb.

Somone may have left out some carb parts during the rebuild. Have the sparkplugs ever been wet with all this cranking? I would call your local Case/IH dealer and see if they have a breakdown on that carburetor showing all the parts. Ask them to emaill you a copy or fax it if you have a fax. Then disassemble that carb and see all the parts are in the carb. Its not like you have a 4 barrell carb. Those carbs are very simple. Is there a main jet adjusting screw on that carb? The old lettered tractors like the H & M had this. So do garden tractors
that's how you enrich the fuel mixture by opening them. Here's one off my old Toro mower. Hal

I am having the exact same problem with my 464. I can finally get it started but you have to keep your fingers on that choke all the time. And the govenor doesn't react the way it should. I am going to have to take it somwewhere to get it fixed. I have done everthing these guys have suggested that you should do but nothing seems to help.

These carbs don't have the main jet adjusting screw. It's controlled with the electronic shutoff.

The only adjustment screw on these carbs is the idle screw.

If I had the tractor here I'd take a picture of the carb and post.

The mechanic thinks he found another carb he can try. Then we'd at least know if the issue is confined to the carb.

I asked the mechanic about this and he said he checked all around for air leaks. He didn't say he checked for an internal one. He did say that he looked inside the manifold and he said it looks brand new.

Even though this is a mid 70s tractor. It only has around 1500 hours on it.

Do You know the make and model number of the carburetor? Hal
PS: I still think something was left out during the rebuild.

Sorry, still don't have the model number.

They found an old carb that he said wasn't in very good shape. Not exactly the right carb but bolted on. Ran it and it ran like a champ.

So they're putting a new Zenith Carb on it and should have it back in 4 or 5 days.