Fuel pump issue

[WranglerX]

Didn't someone say that the pump has to rotate twice for every one rotation of the engine? Maybe the pump is on the pin correctly, but the engine is in the exhaust stroke when it needs to be on the intake??? Wouldn't that mean, the pins line up, it's just on the wrong TDC?

IF fuel pump is driven off cam its probable 1 revolution of pump for every 2 revolutions of crank.... I believe this engine is typically a 4 cycle so it is a 720° engine cycle and pump only needs to deliver fuel on intake stroke which is one of the four (180°) cycles of engine ....

Dale

 

[WranglerX]

This is the part in the repair manual that mentions injection pump removal / installation
View attachment 678767

So basically, the pump shaft should be in alignment with the dowel pin, and the timing marks should line up again. It makes no mention of any other timing adjustment being needed - It does not mention any risk of mounting the pump 180 degrees out of time, so I would not expect that it was possible to do that since it is not mentioned in the repair manual.

So, again, the only reasonable explanation I can think of, would be if the forces that broke the internals of the pump also made the pump timing gear skip one or more teeth.

So I guess I have to remove the valve cover, and rotate the engine to TDC on cylinder 1 compression stroke, and verify if the letter "C" in the fuel pump inspection window is in alignment (this is from the manual)
If not, that would verify that the engine and pump are out of time, and I have to disassemble the engine further to get access to the timing case and adjust the timing gears.

Kind of in back of my mind but did not to want to mention it....

Dale

 

[CoyPatton]

IF fuel pump is driven off cam its probable 1 revolution of pump for every 2 revolutions of crank.... I believe this engine is typically a 4 cycle so it is a 720° engine cycle and pump only needs to deliver fuel on intake stroke which is one of the four (180°) cycles of engine ....

Dale

Dale has done a much greater job of explaining the details of the pump and engine rotation explanation.
In my 1st comment, I stated it sounded as though the engine and pump are 180 degrees out of time with one another.
This would mean instead of fuel being delivered to each cylinder shortly prior to the compression stroke (4 stroke engine which I am 99.9% sure this is) fuel is delivered shortly before the exhaust stroke.
My suggestion remains to retime everything according to the procedure as printed in a service/repair manual for the tractor.
If as others have indicated the cam turns 1x for every 2x of the crankshaft, out of time is possible with alignment of the cam and pump.
If you want to not follow the service manual procedure, pull the pump, rotate the engine 1 full turn of the cam shaft, reinstall pump, bleed fuel lines from tank to injectors, try starting engine. Since you do not know where the pump timing is located, it may take several tries to find the correct timing alignment.
Seems simpler to find timing procedure for pump install and follow it.

 

[Tinhack]

If not, that would verify that the engine and pump are out of time, and I have to disassemble the engine further to get access to the timing case and adjust the timing gears.

NO! NO! NO! Do NOT change anything on the engine side or you'll be in deep shmit! The engine timing is fine. You need to match the pump to the engine.

I'd pull the injectors so you can turn the engine over manually. You may have to turn the engine over 2-3 times to verify #1 TDC is entering the power stroke (both valves closed). It can be at TDC twice during a cycle. I'd also attach the injectors to the lines so you can see which one is "firing" and when. When number one is coming up to TDC, number two injector should be firing since #2 should be on it's intake stroke. (I'm assuming the firing order is 1,2,3,4.)

Injectors are not spark plugs. They are more like individual carburetors. They need to spray during the intake stroke. Spraying at TDC on the power stroke won't do anybody any good. It's too late then.

 

[jaydee325]

The fuel injection event in each cylinder of a diesel engine typically occurs 15 to 20 degrees before top dead center of the compression stroke.

 

[Tinhack]

Ok, my mistake. So the air charge is already there and the fuel is injected during compression. That still makes #2 the cylinder of interest when #1 is at TDC. (The injector event already occurred on #1.)

You could just as well start at #4 TDC and watch for #1 injection event. But you need to know where you are--Engine and pump.

 

[Kaltoft]

NO! NO! NO! Do NOT change anything on the engine side or you'll be in deep shmit! The engine timing is fine. You need to match the pump to the engine.

And as far as I can tell, that is done in the engine timing case by making sure that the camshaft, idler, crank, and injection pump gears all align on their timing marks. You cannot adjust the timing on the pump.

 

[jaydee325]

In a 4 cylinder engine the usual firing order is 1-3-4-2. What that means is cylinders 1 and 4 are paired cylinders. Also, 3 and 2 are paired cylinders. So, when for example, #1 is at TDC of compression stroke, 4 is at TDC of exhaust stroke.

The paired cylinders can be used to assist in timing a 4 stroke engine. All you have to do is remove the valve cover, rotate the crank and observe when cylinder #4 valves "rock". Rock means you will observe the exhaust valve closing as the intake valve opens (rocker arms "rock"). Cylinders 1 and 4 will each be at TDC with #1 at TDC compression. At this point you can get exact with what ever means is available as far as engine timing marks (front balancer or front pulley etc). Now you can set the fuel injection pump at its timing marks for #1 injection event. This will be covered by the manual that hopefully you have since this will outline where the timing marks are located and what orientation they are required to be.

If you don't have a manual, you should get one. This should be fairly easy since this engine has been around since the early 60's.

 

[WranglerX]

The fuel injection event in each cylinder of a diesel engine typically occurs 15 to 20 degrees before top dead center of the compression stroke.

Yeah but close enough to TDC on compression stroke to be valid in discussion...

And on a gas engine ignition timing can be anywhere form 7.5 to 30 Degrees BTDC ...

Really only difference is instead of ignition event is initialized by sparkplug on gas engine ands in diesel ignition event is initialized by the injection of fuel...

Dale

 

[WranglerX]

People stop to consider, the pump engagement pin on engine can only fit one way on pump, impossible to get it out of time.... The splines on pump drive are also keyed to pump shaft so it only goes on one way.... By the shear nature of the mechanics the pump can not possible be assembled on engine out of time (except for a few degrees at mount) ....

IF the above is not true, the pictures are lying to all of us.... Don't believe the problem is "timing"..... believe something else is askew here....

Maybe the gearing inside engine case has jumped a few teeth, maybe cam drive is a few teeth off, but then it would not run good with starting fluid down air intake....

Are we actually sure the pump is delivering fuel to injectors (at any time in engine cycles)? Is it possible the brand new or rebuilt pump is defective?

Dale