Fordson Super Major starts but runs slow.

Nick Ballem

New User
I have a Fordson Super Major. Right now I am have a very hard time starting this tractor in the winter time. I have no problems starting the tractor in the summer, fall or spring. Basically any time the temperature outside is below freezing the tractor won"t start. I"ve bleed the fuel system so there"s no air in the fuel. The fuel is not frozen because I won"t be able to bleed the fuel system if it was frozen. My governor is pneumatic and appears to be working properly. I"m getting fuel into the engine because there is lots of white smoke coming out. Today I was able to actually get the engine started with a hair dryer, but the engine will not speed up. I tried moving the throttle and no change. Any ideas on what to try next? Like I said early this tractor will start with no problems in the summer!!!
 
Hi:

I have a 1963 FSM.
I live in Canada and in the winter I have no problem starting once I plug it in for a few hours.
I have a heater in the bottom rad hose.
They are about $40 and quite simple to install.
Kenneth Armour
 
can't explain why it runs slow after start but in south east vermont a lower radiator hose heater has been good for me for over twenty years i think i got mine from napa
 
Hi
If you got a vacuum governor and it"s that cold it could be the leather diaphragm is not flexing in the cold. those diaphragms are lightly oiled. and pulled to rev the motor by the difference in vacuum in the 2 lines that come from the intake manifold, so if the oils cold it will be so stiff to move, I think some later ones might of even had a rubber diaphragm in so cold would affect this also. or the linkage in the pumps binding when cold. That would be my guesses as to why it works in the summer and not winter.
when you got it running try warming that housing where the pipes go into the vacuum unit on the pump and see what happens,to throttle response. if it"s that diaphragm it should start working right.
you do also know the pump has excess fuel button for cold start just at the bottom of the stop linkage. should be a little round push button poking out.
Also as others have said you need a block heater of some sort, cranking/ starting it like that when cold will seriously shorten the life of the motor.
Had a customer tractor out side this week minus 20oc, just for fun turned the key it would not even turn the motor over. Plugged it in Thurs night went to it yesterday morning( Friday) 2 turns and it fired right up just like plus 30 temps I don"t usually leave them on that long but didn"t have a spare timer around.
Regards Robert
 
Hi, Thanks for your comments.

It"s a rubber diaphragm. I had the governor apart a couple of winters ago. Back then I found that the dampening valve had fallen off. I fixed it and put the governor back together. It doesn"t seem to be stiff because I can hand operate the fuel stop lever. When I disconnect the pneumatic tubes off of the governor, plug the two holes with my fingers and try to move the fuel stop lever back or to the left, I feel a lot of resistance. This tells me there are no air leaks. When I move the fuel stop lever back or to the left and then plug the holes with my fingers, the spring and diaphragm returns back to normal position. According to the manual this procedure tells me that the diaphragm is leaking air!!! I"m confused, It leaks air in one direction but not the other?

I"ve attached a diagram of the diaphragm unit. The part that I don"t understand is when you pull the throttle to give more gas you end up moving the butterfly valve closer to the closed position, which causes the engine to suck harder on the governor diaphragm. This action looks like it decreases the amount of fuel by moving the fuel control rod to the right. Isn"t it suppose to be increasing the fuel, not decreasing it? That"s the part that I don"t understand about the governor.

I am using the excess fuel button for cold start but it doesn"t make a difference.

I think I will try using a rad hose heater. I"ve been trying to avoid this because it"s a band aid approach, but I"m running out of ideas to try. I would rather like to use an engine block heater but I can"t find a location to put the engine block heater into. Anyone know where I can install an engine block heater?

four years ago this tractor started at -18 Celsius with only about 15 second of turning the engine over with no rad hose heater and not using the excess fuel button. Something changed and I can"t figure out what!

Thanks,
Nick
a139421.jpg
 
Hi. You are probably all advised out on this one but I've had a little think to see if theres any thing else to suggest. Assuming you have anormal simms pump, when you press the cold start does the rack actually move? you'll need to take the side panel off to check. If the air breather has moisture in it it will freeze up and not allow the damper to move properly. You could try wrapping a cloth around the diaphram and pouring hot water over it. The cloth will retain the heat and get rid of any ice. You have probably already tried removing the air intake pipe and holding a twist of burning newspaper over the intake whilst you use the starter so it sucks hot air into the engine, but its worth a mention. (thats my favourite). Is the butterfly valve in the intake working correctly. If you've already been down these lines then sorry to bother you. Have a nice season. Mike
 
Hi:

The concept of rad hose heater vs. block heater been a band aid approach is a myth in my opinion.

The rad hose heater works just as well (in my opinion). The rad hose heater on my FSM works like a charm, I also have them on my two antique Series Land Rovera and they work like a charm.

Just my two cents worth.

Kenneth Armour
 
Check the oil bath air cleaner got my major to start using hair dryer on intake but it would not rev up took oil bath off almost all water frozen.cleaned it out fresh oil ran great! Just my thoughts.
 

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