Ford 4600 Diesel has me stumped!

liammaestro

New User
Hi everyone, I have a bit of a predicament here. I recently acquired my first diesel tractor. It is a 1981 Ford 4600 with the 201 diesel engine. It belonged to an old farmer down the road who recently passed away and his wife just wanted it out of her way so I purchased it from her. Prior to my acquisition of this tractor it had been sitting in his barn untouched for at least a year. The Story Goes it always ran and it always started right up without fail. All I needed to do is replace the battery as it was long since gone. Well, as these things usually go for me it was not that simple.

After purchasing a new giant battery and replacing the starter because it appeared to be fried the tractor still won't start but it turns over just fine and easy. A friend told me to just replace the fuel injectors so I did with no change. I then proceeded to change the fuel filter and take off the fuel lines just to make sure nothing was clogged. Everything seem to check out fine. I put in new gas and still can't get this thing to go. I bleed the fuel system according to the owner's manual starting at the fuel filter and working my way over to the fuel pump and then cracking the lines at the injectors. If I have the bleed screw out on the fuel pump it will shoot fuel to the front tire. To me that seems like the fuel pump is working??? But then again I'm not really sure because I've never played with the diesel tractors much. It has the CAV rotary fuel pump. I give it a quick spray of ether it will start right up no problem until the ether is all gone and then it just cranks but doesn't seem to be getting fuel. Although there is fuel at the injectors.

I'm at my Wit's End of what to do! Is it the fuel pump do you think? Should have be squirting a lot harder or a lot more? When I crack the fuel lines at the injectors there's fuel coming out but I don't know how hard it should be spraying. Am I missing something simple and obvious that most diesel tractors require me to do? I know the fuel shut off pull switch should be pushed in to start and when I pull the throttle linkage on the fuel pump itself seems to be moving just fine. The fuel pump does have a slight leak and it looks like it's coming out of the throttle lever on the pump but I didn't think that that would cause such a problem.

I'm new to this diesel Fords. I have a 1949 8N and a 1971 Ford 2000 gas both of which I keep running and they are operationally in great shape but this one has me stumped!

Any suggestions??? Don't be afraid to point out the obvious because it probably isn't obvious to me. Many thanks all.
 
I put in new gas

I hope that you typed "gas" but actually put in new diesel fuel!!! If you actually put in gasoline then you have created more problems.

If you put in new diesel fuel, and with everything else that you've done, it sounds like you need to bleed the air out of the fuel system. If you don't have an Operator's Manual and a Service Manual, get them both. The Operator's Manual should have the procedure for bleeding the air out of the system.
 
I am hoping you pushed the fuel stop in.

You have created a lot more work by opening everything up, now it needs bled.
 
CAV rotary pump been sitting to long with this junky fuel we get now and metering valve stuck. Mite tap on top where throttle and kill levers are and get it loose. Some have had to pull that cover and unstick it. When get running add some oil to fuel to help keep from sticking.
 
I think Shaun has it pegged.
Its your metering valve.
Shut fuel off at the tank.
Remove the throttle rod and shut off cable.
Cut the wire that has the lead seal on it.
Remove the two nuts that hold the top cover on the pump.
Carefully lift the cover of the pump about 3/4".
Do NOT overstretch or remove the spring that is attached under the cover.
The photo shows it backwards from what you will see. Note the slide bar #3. That will be right in front of you when you lift the cover. That slide bar operates the metering valve. See the red arrow. That is your metering valve. Metering valve has a very weak spring that should return it to run position. They get stuck in the off position. Free it up with a small screwdriver or popsicle stick - move it back and forth till it returns on it's own.
Get the slide bar located properly - it's tricky. Replace the cover. Replace the nuts.
Some say you will wreck the gasket under the cover when you do this. I have done this half a dozen times and gasket was always fine.
Turn on the fuel and bleed the filters. Bleed the pump. Crack all 3 injector lines and bleed them simultaneously. Then retighten. It should start then.
Remember this pic is backwards.
It really is Very simple to do so don't be skeert of it.
Let us know how it goes.
a275076.jpg
 
PS,
There is a little washer under each of the nuts on top of cover. Don't lose them or it will leak there.
Also, many of us now pull the kill cable out to shut down the engine. Then push it back in. That will leave the metering valve in the run position and it won't stick off again.
 
Well.. it looks like you don't need my help.. LOL..
Good job Ultra.!!! & great pic..
but I'm not with ya on the gasket thing.. He already stated his throttle shaft was leaking..
Might as well get the "mini kit" off ebay.. top cover gasket, 4orings & 2fiber washers for 12.00.
Good luck w/ the repair.. like others have said, don't be skerred.. you have a lot of help here..
 

Thanks.
One of us should have mentioned it's worth the cost of a couple cans of brake cleaner to clean the pump off first.
He doesn't need ANY dirt in there.
 
Well, looks like I have a new fuel pump in my future...I attempted to remove the two nuts from the studs that hold the top cover in place. They both seemed to be seized in place.
I just turned a little harder and the first one snapped the stud. The second one followed with the same result. And yes I am sure I was loosening and not tightening. They wouldn't
be reversed threads would they? But ultimately it also appeared that both of you were correct on the issue of the metering valve and rod. Neither had much movement. I will start a
new post asking for input on any decent aftermarket fuel pumps. That's the way this tractor goes for me! I'll get 'er running whatever it takes!
 
Well.. it looks like you don't need my help.. LOL..
Good job Ultra.!!! & great pic..
but I'm not with ya on the gasket thing.. He already stated his throttle shaft was leaking..
Might as well get the "mini kit" off ebay.. top cover gasket, 4orings & 2fiber washers for 12.00.
Good luck w/ the repair.. like others have said, don't be skerred.. you have a lot of help here..
Are there many items that get really worn in the pump or will a new reseal kit help things
 
Setting unused very long the internal rotor plungers are probably stuck, I see that a lot lately on pumps I tear down for repair/cleaning/recalibration. Any water in fuel, or bio diesel will stick parts quickly after setting a short time.
 
Well, looks like I have a new fuel pump in my future...I attempted to remove the two nuts from the studs that hold the top cover in place. They both seemed to be seized in place.
I just turned a little harder and the first one snapped the stud. The second one followed with the same result. And yes I am sure I was loosening and not tightening. They wouldn't
be reversed threads would they? But ultimately it also appeared that both of you were correct on the issue of the metering valve and rod. Neither had much movement. I will start a
new post asking for input on any decent aftermarket fuel pumps. That's the way this tractor goes for me! I'll get 'er running whatever it takes!
Have your pump rebuilt by a reputable rebuilder.
 

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