Ford 3cyl diesel hard to start with new pump.

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Got a pump from a member here that was rebuilt. While I was waiting I got a used pump that leaks like crazy but the tractor fires up and runs good. With the new pump it will not start without a whiff of ether. Its 96 here today so I know its not too cold. I get puffs of white smoke but it just wont start. Switch back to old pump and it fires up fine. But the tractor runs better with the rebuilt pump after I get it started. Timing is set to 1/2 degrees advance on both pumps. Fuel flow at the pump is good. Should I put more timing on the rebuilt pump or is there something internal I should be looking at? At this point I could swap a pump in my sleep but Im kind of tired of doing that.
 
What model tractor, and/or what model engine?

It is surprising that the one which leaks like crazy is the one you are not having problems with, usually leaky pumps entails that air is getting into your fuel supply and can prevent your pump from priming.

On the subject of priming, have you opened up the bleed screws on the rebuilt pump and thoroughly bled the system? On my tractor, the manual only mentions one of the bleed screws, when there are two. One to bleed air from the main cylindrical casing on one side of the pump, and another on the opposite side of the pump to bleed air from the top portion of the pump where all the ligatures are located. Next, you will need to bleed air from the fuel lines that lead from the pump to the fuel injectors. You do this by disconnecting the fuel lines at the injector and turning over the engine until you have good flow.

I mention this, because after rebuilding a fuel pump, I noticed how much fuel fills up all the nooks and crannies of the pump, all those nooks and crannies with fuel in them are replaced by air during the rebuild process and have to be flushed out.

The only other thing that makes my head itch a little is the 1/2 degree advance on the timing. You might have to set your timing to dead zero for the rebuilt pump in order to get it timed correctly. This is because the fuel pump has its own timing settings, and sometimes they may be inadvertently reset during the rebuild process. Another member who is more knowledgeable than I would probably be a better source in respects to the timing situation than I.

Well, for what it is worth, that is my $0.02 worth.
 
(quoted from post at 23:58:14 08/12/21) What model tractor, and/or what model engine?

It is surprising that the one which leaks like crazy is the one you are not having problems with, usually leaky pumps entails that air is getting into your fuel supply and can prevent your pump from priming.

On the subject of priming, have you opened up the bleed screws on the rebuilt pump and thoroughly bled the system? On my tractor, the manual only mentions one of the bleed screws, when there are two. One to bleed air from the main cylindrical casing on one side of the pump, and another on the opposite side of the pump to bleed air from the top portion of the pump where all the ligatures are located. Next, you will need to bleed air from the fuel lines that lead from the pump to the fuel injectors. You do this by disconnecting the fuel lines at the injector and turning over the engine until you have good flow.

I mention this, because after rebuilding a fuel pump, I noticed how much fuel fills up all the nooks and crannies of the pump, all those nooks and crannies with fuel in them are replaced by air during the rebuild process and have to be flushed out.

The only other thing that makes my head itch a little is the 1/2 degree advance on the timing. You might have to set your timing to dead zero for the rebuilt pump in order to get it timed correctly. This is because the fuel pump has its own timing settings, and sometimes they may be inadvertently reset during the rebuild process. Another member who is more knowledgeable than I would probably be a better source in respects to the timing situation than I.

Well, for what it is worth, that is my $0.02 worth.


The tractor in question is a 1969 Ford 4000.

I have gone through the bleeding process twice. I have the tank full and start at the filter. he the screw on the side of the pump. Then I crack the lines at the injectors. I get a good squirt out of all three lines. Much better than the leaking pump. I think the air is out of the system. I mowed for about 3 hours with the new pump and the tractor runs great.

I am going to set the timing at 0 and see if that helps any.
 

Theres 2 members here that are professional pump rebuilders, was it one of them or just a individual that knows how to work on them
If it was one of the 2 call them and send the pump back

Once the engine has been run for a while unless theres a fuel delivery issue its hard to get air back into the system without there being a visible leak
If the check valve in the fuel inlet at the back of the pump isnt sealing the engine will be hard to start, same if the transfer pump vanes are worn
 
(quoted from post at 06:46:04 08/13/21)
Theres 2 members here that are professional pump rebuilders, was it one of them or just a individual that knows how to work on them
If it was one of the 2 call them and send the pump back

Once the engine has been run for a while unless theres a fuel delivery issue its hard to get air back into the system without there being a visible leak
If the check valve in the fuel inlet at the back of the pump isnt sealing the engine will be hard to start, same if the transfer pump vanes are worn

It was one of the known pump builders here. And they have been helpful but this has been going on since March and the pump has been sent back twice. They are still trying to help out but I am also trying to get some other ideas as to the possible problem. And in no way am I trying to drag anyone through the mud. Like I said the builder has been very helpful but sometimes another pair of eyes can see what I can't.
 

Well since it starts good and runs with the old pump I dont think its a fuel delivery issue
That said a friend with a 4610 recently inquired about rebuilding he engine, it had high hours and would not start without a short of ether every time
Compression was a little low but Ive seen worst, replaced the vanes in the back of the inj pump and it now fires up hot or cold

Id swap the fuel inlet and transfer pump vanes from the leaking pump to the rebuilt one and see if that makes a difference
Simply disconnect the fuel line and remove the four 5/16 bolts from the back of the pump, remove the fuel inlet and then the vanes just inside the pump
Swap those parts to the rebuilt pump and see if that helps
 
(quoted from post at 07:30:21 08/13/21)
Well since it starts good and runs with the old pump I dont think its a fuel delivery issue
That said a friend with a 4610 recently inquired about rebuilding he engine, it had high hours and would not start without a short of ether every time
Compression was a little low but Ive seen worst, replaced the vanes in the back of the inj pump and it now fires up hot or cold

Id swap the fuel inlet and transfer pump vanes from the leaking pump to the rebuilt one and see if that makes a difference
Simply disconnect the fuel line and remove the four 5/16 bolts from the back of the pump, remove the fuel inlet and then the vanes just inside the pump
Swap those parts to the rebuilt pump and see if that helps

I will give that a try and see what happens.
 
Move the top of injection pump toward the engine, timing needs RETARDED to help with hard starting cold. The Ford CAV DPA pumps have plenty of speed advance after engine
starts. White smoke means fuel is in chambers, but too cold to fire due to low compression OR too early timing.
 
(quoted from post at 15:19:01 08/14/21) Move the top of injection pump toward the engine, timing needs RETARDED to help with hard starting cold. The Ford CAV DPA pumps have plenty of speed advance after engine
starts. White smoke means fuel is in chambers, but too cold to fire due to low compression OR too early timing.

After adjusting the timing as close to 0 as I could get it and putting a new starter on I am happy to report the tractor starts right up. The old starter was cranking much too slow. Now my only issue seems to be the idle. Sometimes when I close the throttle it idles fine and other times the tractor will sputter and shut off.
 
This made me very happy to hear. I am glad moving the timing back to 0 got things working a little better for ya.

You can probably adjust the idle on top of the fuel pump, on my tractor it is the ligature toward the rear of the pump that operates the throttle. One side of the ligature is the governor which is usually sealed (don't touch), the other is the idle screw. I would perform 1/4 inch turns until she is idling better.
 
(quoted from post at 04:52:53 08/15/21) What is the low idle speed setting?


It Idles at 850 on the tach when it does idle. I will say after working it all weekend that maybe clearing up. I didn't have any idle issues yesterday. We will see how it goes the rest of the week.
 
(quoted from post at 04:28:02 08/16/21)
(quoted from post at 04:52:53 08/15/21) What is the low idle speed setting?


It Idles at 850 on the tach when it does idle. I will say after working it all weekend that maybe clearing up. I didn't have any idle issues yesterday. We will see how it goes the rest of the week.


Well I thought I was out of the woods but that's not the case. I mowed for about 3 hours last night. I pushed the throttle closed and I might as well have pulled the cutoff. After it cooled off a bit the tractor would idle fine. Not sure what to look at now.
 

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