Starting problem question...300U

Dave H (MI)

Well-known Member
Here is one that I cannot quite get my mind around. Maybe someone can get me started in the right direction.

Tractor is an older "restoration". A lot of work was done to it and it has been a good starter, runner and worker. It pulled a 300 gallon white sprayer on corn this past Spring and had no issues up or down hills. It is set up to be my snow removal tractor out to the farm and rental property this winter. It did a great job on our recent 16-18" snowfall except that it is reluctant to start.

First, it wants no choke. It will flood if choked. Even without choke, the throttle must be all the way down to make it start. It will start and run for 2-3 seconds and stall. If you try to throttle it up it stalls faster and will not start with more throttle either. So it starts with no throttle and runs the 2-3 seconds. You have to repeat this many times (more than 10) before you notice it may be running a second or two longer. It will slowly increase how long it runs until it just stays running. THEN you can VERY SLOWLY increase throttle until it catches and starts to increase RPM's. Too fast and it stalls. Once it warms up it runs good and restarts easily.

I'm afraid this one is new territory for me. They either start good in cold weather or they flood...never had one that did this. Ideas anyone?
 
Just a shot in the dark here, but next time when you get it running and warmed up........take a can of starting fluid and spray some around the intake manifold.

Not in the intake, just the manifold where it bolts to the head.

If you can hear the engine surge some.......I'd say you have a bad intake gasket and it's sucking air.
 
Dave, I also have a 300 Utility with an IH 34 loader my dad bought used in 1966. Maybe 20 or 25 years ago we had a problem similar to what you described. Think I fixed it by tightening up the intake manifold bolts. But mine also has a block heater I put on back in 1966. Like yours, my 300 does not start very good and run good until it warms up in cold weather below 40 degrees. But if I plug in the block heater for about 1/2 hour, it starts right up with just a touch of the key and runs fine. I do give it full choke at cold startup and then maybe 1/2 choke for a couple of minutes. So just something you can easily try. But if you need it in cold weather to plow snow, I would suggest adding a block heater. It makes day & night difference in cold weather starting. Al
 
I have an easy way for you to fix that 300U problem just buy the one I have it starts easy or it did the last time I started it.
Low compression can cause that as can a weak spark or a vacuum leak or timing being off some
 
Is the gas shut off when parked? Maybe it is flooded before you use the choke. Does it smoke black in those 2 or3 seconds when it try's to run? If not I would be looking at the ign. especially the condenser. Champion plugs? What gap? Plug wires copper wire? Compression test lately?
 
Is the air cleaner cup clean? What weight
of oil is being used in it? Too heavy of
oil in the winter may cause a problem.

I'll go along with the vacuum leak thing
for starters. Then points/ condenser.
 
Sounds just like my old Massey. The needle valve in the carburetor leaks just enough that there is a bit of gas in the intake hose after the tractor has sat for a few days. This is just enough to make it fire right up, without the choke, and then of course it stalls. What works for me is once it starts, then pull the choke out and gradually push it in til the engine runs smooth. It starts right up because there is some gas in the hose, then stalls once that gas is burned up. It floods when using the choke because there already is enough gas there to start it, then choking enriches the mixture even more, flooding it. Opening the throttle allows more air in, leaning the mixture then it stalls. Most of those old gas engines will need some choke for the first couple of minutes. Hope this helps.

Ben
 
I also believe you need the choke just after it fires the first time. Try this: when you shut it off, turn off the fuel at the tank and let it begin to die from starvation, then turn off the key. On the next cold start, open the fuel and wait for 15 seconds, pull the choke and start it feathering in the choke as it warms. I have been around your situation and found the answer to be a fresh fill of fuel in the carb from shut off, and use of the choke. This is when cold (less than 35 degrees F) Jim
 
My H will do that if I do not give it a very quick burst of choke when cold, notice I said very quick burst of choke.

You might want to richen the idle mixture about 1/2 turn, should help a little with the stumbling.
 
I appreciate the good ideas. I'll take a look at it again to see which is the solution as soon as we get the rest of the corn in. Thanks!
 

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