[KWA]

While working on a plumbing problem my friend once told me "You can never touch just one fitting". Meaning, once you fix this issue, another will pop up.

I suppose the same applies to Diesel Fuel Systems.

I had a very simple problem. The cut off lever on the fuel injector pump was leaking. Not terribly, but enough to notice. So.... I did some research and decided to buy an o-ring kit for the top half of this pump and fix it.

I removed the cover, removed the throttle shaft and replaced the 2 o-rings. I did the same with the cut off shaft. I also replaced the main gasket for the cover and put it back together.

The tractor would not start. OK fine, I need to bleed the fuel line. So I filled up the tank, opened the fuel filter bleed screw until fuel ran out the top. Closed it. Opened the injector pump bleed screw and cranked the engine. Fuel forcible squirted out so I closed it. Then I cracked the fitting the injectors and cranked the engine. Very little fuel came out. Hardly anything at all. Certainly not the high pressure squirt everybody warns about not getting hit with. Less than a dribble.

So.... I took the top off again, checked the springs, shut off rod, etc. and closed it back up and tried again. Same results. Then I took off cover and removed the governor plate and cleaned the crud off the throttle valve and assembly. Put it all back together, bled it again. Nothing.

I suspect the high pressure side of the pump is not doing anything or the fuel is cut off to it but I don't know why. All I did was take off the top and change a few o-rings. Certainly nothing worthy of all this angst.

As a test, I cracked the nut on the #1 Cyl line at the pump and cranked the engine. I was expecting fuel to shoot out with force like when I took out the pump bleed screw. Hardly a dribble. I can't say if that is normal or not because I've never done this before. My expectation was a high pressure mess and I got nothing.

Has anybody seen this before? Is this something simple I overlooked? I thought this would be a 30 minute o-ring job and it turned into a weekend of frustration. The tractor ran fine before I took the lid off the pump. (other than the leak) Now I can't get fuel to the injectors.

I guess you can't touch just one tractor part either. The good news is the leak has stopped. The bad news is

I can't start the tractor.

 

[thepumpguysc]

It might be the throttle assembly on top.. U might have missed the tang w/ the lever..
Happens ALL THE TIME.. recheck it..

 

[KWA]

It might be the throttle assembly on top.. U might have missed the tang w/ the lever..
Happens ALL THE TIME.. recheck it..

Actually I've tried it with and without the throttle linkage attached. I moved both the throttle and cut off lever manually without anything attached to make sure they were moving and still no fuel to the injectors. I did take the top apart and clean it, but nothing changed. Still scratching my head.....

 

[Hacke]

You can not get pressure without an obsticle. Take a garden hose and let the water run freely out of the hose end. No drama there. Put your thumb over the hose end. Now you have an obsticle and the pressure rises in the hose. If you release the thumb pressure just a little, you will get a small opening where the water squirts out.

Same thing with your fuel lines, the injector valve is the thumb. Inside the injector is a valve that is shut by a spring. When the pressure is high enough to lift the valve, it opens and you get the high pressure squirt you where expecting. So, from the cracked line you will not get a dangerous squirt.

You need to get the air out of the injector lines, otherwise the pump can not build up the pressure against the injector's valve. The air compresses and act as a spring. Therefore you need to crank the engine and let the air out of the cracked lines. This may take quite a while to do, because the pump delivers just a small amount of fuel each time it feeds an injector.

I cut three clear hoses and attached one to each cracked line, and then let the other ends go to the tank's filler hole. Then I connected a car's battery to the tractor's battery with jumper cables. With the car's engine running, I sat on the tractor, cranked and watched the fuel and air bubbles slowly walking up the hoses. Finally there was no air bubble and the work was done, without any mess.

Remember: Shut off knob at in position and throttle handle fully engaged.

 

[KWA]

Your garden hose analogy makes perfect sense and from all that I've read so far everything points to air in the lines. There have been a couple times the tractor fired two or three times and quit. Probably got one to two good squirts followed by an air bubble. Also, I've probably been cracking the lines too much to keep any kind of pressure on the fitting. That may be why I only get a bubble laden dribble instead of a the pressurized squirt I was expecting. I've tried not to crank the engine more than 10-15 seconds at a time because I didn't want to go so hard on the starter. I would wait a minute or so and try again. I've read others talking about cranking for much longer and even dragging their tractor around the yard to make it pump faster.

I like the clear hose idea. I assume you mean take the fittings completely off the injectors at the cylinders and shove the tubes over the ends of the fuel lines. From there run the tubes back into the diesel tank? That's what I am visualizing. Once I have the 3 plastic hoses connected I would imagine it might save some time if a took a turkey baster type device and squirted some diesel from the top of the hose back down the lines. I'm thinking I could tap on the lines and wait a minute or so and let the air bubble to the top. Then I could crank the engine to see what else may bubble out?

On a side note: Has anybody ever retro-fitted one of these CAV pumps with a manual primer pump? I've seen some manual Diesel pumps online for cars and trucks but am not even sure where one may attach it to this system to make it work as intended. That was just a thought I had to solve this problem in the future. I hate doing the same work twice. At any rate, I'm going to give the clear tube idea a try. Thanks to all for your suggestions. I'll post my results when I have them.

 

[thepumpguysc]

What I'm talking about is the TANG on the throttle shaft & the HOLE in the throttle LEVER.. Ive seen it a thousand times where someone misses the HOLE & they tighten down the nut.. so now the throttle is actually stuck in the shut-off position & wont pump enough fuel to start or run the engine..
MAKE SURE to have the throttle WIDE OPEN & the sh-off lever to the RUN position.
{Long end of the sh-off levetowards the engine}..

 

[KWA]

What I'm talking about is the TANG on the throttle shaft & the HOLE in the throttle LEVER.. Ive seen it a thousand times where someone misses the HOLE & they tighten down the nut.. so now the throttle is actually stuck in the shut-off position & wont pump enough fuel to start or run the engine..
MAKE SURE to have the throttle WIDE OPEN & the sh-off lever to the RUN position.
{Long end of the sh-off levetowards the engine}..

10-4 will do. I left the battery on charge last night so it should be good. If I get home at a decent hour I'll check everything again and give it another try. Thanks

 

[Hacke]

...
Also, I've probably been cracking the lines too much to keep any kind of pressure on the fitting. That may be why I only get a bubble laden dribble instead of a the pressurized squirt I was expecting.
...

Disconnect the lines from the injector. In order to easily get the air bubbles out, you need the lines to be fully open.

...
I assume you mean take the fittings completely off the injectors at the cylinders and shove the tubes over the ends of the fuel lines. From there run the tubes back into the diesel tank?
...

Yes, sorry. English is not my native language and I was not aware of that "cracking" means loosen, not unscrew and take apart. I always thought it meant the latter, because of the phrase "crack a bottle". Now I see someone trying to drink from a bottle with the cap just slightly unscrewed...

...
Once I have the 3 plastic hoses connected I would imagine it might save some time if a took a turkey baster type device and squirted some diesel from the top of the hose back down the lines. I'm thinking I could tap on the lines and wait a minute or so and let the air bubble to the top. Then I could crank the engine to see what else may bubble out?
...

I do not think that would give you a better result than just crank till the air is out. There are passages that will trap the air, #2 injector's line is connected at the underside of the pump, for instance. Better let the pump push all air out.

 

[KWA]

Hacke,

Thank you for the clarification. I will do it the way you explained. There is no reason for me to try to change what already works.

Your English is better than many. I am a multi-language illiterate. I can't read or write in many languages. lol

 

[thepumpguysc]

Can someone explain to me what putting abunch of clear lines on the injector pipes does.??
If your pumping air.. your pumping air.. what do u need the clear lines for??
& once it starts pumping fuel..there isn't enough fuel lose to worry about.. probably less than a tablespoon..
U can leave a line or 2 OFF AT THE PUMP if u want to see it START to pump fuel..then reconnect it so it pushes all the air IN THE LINE OUT.. & starts to pump AT the injectors & then tighten..
Putting extra clear lines on, is a waste of time & money..just my opinion.

 

[dozer966]

Can someone explain to me what putting abunch of clear lines on the injector pipes does.??
If your pumping air.. your pumping air.. what do u need the clear lines for??
& once it starts pumping fuel..there isn't enough fuel lose to worry about.. probably less than a tablespoon..
U can leave a line or 2 OFF AT THE PUMP if u want to see it START to pump fuel..then reconnect it so it pushes all the air IN THE LINE OUT.. & starts to pump AT the injectors & then tighten..
Putting extra clear lines on, is a waste of time & money..just my opinion.

Lol pumpguy I feel your frustration. Think of the shop kid that sweeps the flore. If you were not there to answer his questions and show him the difference he would not know enny better. So I'm assuming the clear lines is to show that there is air or no air in the fuel. Some people understand better with the extra tool/gizmo that takes more time. What ever works. Next time he might not need it because it won't be his first time.

 

[dozer966]

KWA you do not require a primer pump. These Fords are gravity feed no lift pump and no primer pump

 

[Hacke]

Can someone explain to me what putting abunch of clear lines on the injector pipes does.??
If your pumping air.. your pumping air.. what do u need the clear lines for??
& once it starts pumping fuel..there isn't enough fuel lose to worry about.. probably less than a tablespoon..
U can leave a line or 2 OFF AT THE PUMP if u want to see it START to pump fuel..then reconnect it so it pushes all the air IN THE LINE OUT.. & starts to pump AT the injectors & then tighten..
Putting extra clear lines on, is a waste of time & money..just my opinion.

Lol pumpguy I feel your frustration. Think of the shop kid that sweeps the flore. If you were not there to answer his questions and show him the difference he would not know enny better. So I'm assuming the clear lines is to show that there is air or no air in the fuel. Some people understand better with the extra tool/gizmo that takes more time. What ever works. Next time he might not need it because it won't be his first time.

When I came to bleeding for the first time, I was not sure how to determine when all air was out. If it foams, yes that air is out, but will I be able to determine if there are more small bubbles coming out? How do I crank and check the flow at the same time?

With the three clear hoses you can easily check that the pump feeds OK, and that all the air is out. They also show if air continues to come from the pump, meaning that there is a leak somewhere. When work is done, you clamp a hose at the injector line end, disconnect it, connect the injector line to the injector and empty the hose into the tank by raising and releasing the clamp. No mess.

The solution worked well for me. You do as you like.


I do not like the shouting and I do not like to be compared to a kid. If someone is frustrated because of my posts, please accept my apologies. I try to help, but instead I mislead people.

I leave this forum.

 

[dozer966]

Was not comparing enny one like a kid it was just a scenario. If it works for you all the power. I did not mean to offend no one. Hacke pleas accept my sincerest apologies.

I as a young lad sweeping the shop flore had a licensed mechanic who took me under his wing and showed me and explained things like what to look for. Your clear tube trick is a good tool for someone who has not done this. It's a different visual learning experience. And yes it is a very clean way of doing it.

Sorry for offending you. It was not my intention.

 

[KWA]

OK - Here's what I discovered about using the clear tubes.

1. It does make it easier to see the fuel coming out and the bubbles. Some times it was clear fuel followed by a belch of large bubbles then followed by champagne like smaller bubbles. Even after several cranks I was still seeing small bubbles and only had a few inches of fuel in the line.

2. It did keep the job cleaner. The fuel stayed in the tube instead of running all over the head.

3. I could also confirm that the cut off valve was working. Crank with it on and I saw bubbles. Crank with it off and no fuel to the injectors. Good to know in my opinion.

4. You can also verify that all of the lines were unobstructed and fuel was flowing. It was like a timing light. I could see fuel spurt in line 1, 2, 3, 1, 2, 3 1, 2, 3. etc.

5. I learned that it takes much longer than I thought to push out all the bubbles. I still may not have gotten it all. Why? after I hooked up the lines and cranked it turned over a couple times and stopped. On the second crank I got nothing. It was late, the battery was low, so I called it a night. I'll continue tomorrow.

I also found that the throttle lever can definitely be a problem when reconnecting it. Previously I tried with it on and off with no luck. Probably because I had not bled it properly. But I did disconnect and reconnect again just to make sure and I'm not 100% convinced I had it properly seated the last time I connected it. If you don't have the hole lined up it is easy to push the shaft down a bit into the housing making you think it is seated when it is not. I had to pull up on the shaft several times and try again before I actually got it to engage correctly.

I now know that I am getting fuel to the injectors and all 3 lines are working which means the pump is working as it should. I know the throttle works and I know the cut off works. All good information to have without making assumptions.

All in all I think this is a good procedure for both bleeding the lines and verifying the functionality of the pump. Above is a picture of my tube rig. I did not run them back to the fuel tank. I just laid them over the front hood. I probably did not get more than 6 inches of fuel in the lines before I reconnected them. I'll try to crank it again tomorrow after the battery is charged up overnight. If it won't start, I'll check the lines again for air. My fear is I might have a leak somewhere and it is sucking air back into the system. I don't know yet, just speculating the worse case scenario.

I'll post my additional findings when I have them.

P.S. Thank you Hacke for the suggestion. I think this would be a good exercise for anybody new to bleeding a Diesel system. You can learn a lot from what you see in the clear tubes.

 

[Dmfoste1]

I too am new to the forum. Just picked up a Ford 4500 201 3cyl diesel. Never dealt with tractors this size before. But same principles apply as previous projects. I am attempting to get the old girl running again after sitting for 3years according to the previous owner. Glad to know there are forums like this to reference to. The previous owner did his own so of wiring which made it difficult to figure out what he was doing. I had to decipher his wiring. After that was done I moved to getting fuel to the injectors. Come to find iuo the fuel tank was filled with years of crud, clogging the line before the filter. The injection pump was not receiving enough feul. I took it in to have it cleaned completely. The clear tubes is a good method for seeing what is going on inside the lines. Glad I found your post. Keep us updated.

 

[KWA]

Latest update:

After work last night I had about an hour to give it another try so I disconnected all 3 lines, hooked up my clear tubes again and cranked. #1 looked clear, #2 had a few small champagne bubbles, #3 belched out a pretty good sized bubble. I cranked several more times until all 3 lines looked clear and stopped. I then removed the tubes and reconnected all 3 lines and tightened real good. On the following crank it did like the night before - fired a couple times and quit. Further cranks did nothing. Crap! I cleaned up, put it back on charge and went in for the evening.

I knew I was close but what could it be? How is air still getting in the lines? I thought about it for awhile and came up with a hypothesis. Small pockets of air must be getting trapped between the injector and the line connectors when I reconnect them. OK fine, how do I test this idea?

This morning I had about 15 minutes free before leaving for work. I decided to try one more thing before I left for the day. I took my wrench with my right hand and broke the seal on the #3 line. (The one I saw the most air) and with my left hand I then turned the key to crank it over. (yes, my 2000 starts with just a key) When I saw fuel come out of the fitting I tightened it back up while it was still cranking. Then I stopped. I did the same to #2. Cracked the seal, cranked, saw fuel, and tightened it up. As I tightened #2 it started to turn over on its own. Within a second or two it kept going and came up to full speed! I let it run for a minute or so and ran the throttle up and down. That was working good. Then I pulled the fuel cut off and it died. I waited a few seconds and cranked again. It started right up! I did this a couple times and then shut it down, put it back on the battery charger and left for work.

What did I learn?

It's not enough to clear the air from the pump and fuel lines. You have to also make sure air is all the way out right up to the injector fitting itself. The only way to do this is to break the seal, crank, and tighten the line while it is still cranking. I'm pretty sure it would have started the other night had I not overlooked this one tiny detail.

I also learned that if you use the clear tubes just lay them over the top of every thing and don't snake them under the return lines. It works, but it's a pain when you go to remove them while they have fuel in them. See picture.

On a side note, I know the key thing is not the the original design and bypasses the safety in the shift box. That's how it was rigged when I took it over and I have not gotten around to fixing that yet. I'd like to install a kill switch followed by a push button start but I'm still thinking about it.

Thanks to all for your help and suggestions!

 

[Dmfoste1]

Congrats!!!! Glad to hear you got yours started and thanks for posting the results. Many times I have read through a forum to find the original poster never posts a solution to the question or issue they had.

 

[KWA]

Congrats!!!! Glad to hear you got yours started and thanks for posting the results. Many times I have read through a forum to find the original poster never posts a solution to the question or issue they had.

Thanks. I've noticed that too. I figure if someone is going to take time out of their day to give me advice the least I can do is let them know if it worked and say thank you. When it comes to Internet forums like this I feel that posting your results after asking for help is kind of like payback for the advice. Maybe this conversation will help someone else with a similar problem? If so, then I can feel that I've given a little too and not just taken. I prefer it that way.

 

[thepumpguysc]

Glad it finally worked out.. They can be a real nitemare sometimes to bleed the air.
Happy Tractoring..