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Discussion Starter · #1 ·
I replaced the fuel filter and sediment bowl and capped the fuel pressure sensor and now I can't get the fuel system bled. If I remove the bleed screw on the fuel filter fuel flows from the tank, no air bubbles, so I think I have that. Then I try removing the bleed screw on the injection pump and start using the hand pump. It is really hard to pump, but after a while I get a little air then a tiny bit a fuel. I only get a very small amount of fuel and it is hard to tell if the hand pump is even doing anything. I tried putting that screw back in and cracking the injection lines and I get nothing at any of the injectors. I even tried cranking it with the bleed screw out of the injection pump and nothing came out.

I'm stumped. Should it be really difficult to use the hand pump, or is something wrong there? What do I do next? Any suggestions?
 

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Sounds like hand pump went to heck, should force fuel thru, should be able to hear it push fuel when you push plunger, if you have fuel to hand pump, if you have cracked injectors and no fuel, sounds like pump issues, will it fire with a snuff of ether, not that I recommend it, don't get carried away, sometimes these diesels can be a pain to bleed, Scott.
 

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If this engine has a rotary style injection pump the elastic damper on the governor inside the pump may be falling apart. When this happens tiny pieces of it can lodge in the check valve that is screwed into the top of the pump where the return line is attached.

If the check valve gets plugged there is no longer a differential pressure between the internal charge pump and the pump case itself. It needs this differential in pressure to reset the plunger rollers back into the cam ring as the rotor with the two plungers and rollers rotates from cylinder to cylinder because there are no springs to make the rollers follow the cam.

You can simply remove the check valve in the return line for now. In time the elastic damper will fall apart completely but the governor will develop a distinct aggressive surge once the flyweight cage is being driven by the metal pins that the damper was once located on.

Use a tiny set of snap ring pliers to get the damper holes stretched over the pins if you are a do it yourself kind of guy. It's just a pump.
 

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i put an electric fuel pump on my L2 makes all the differance.these combines run out of fuel often if you are on a side hill and all of the fuel sloshes to one side of the tank. just loosen lines at injectors and crank engine until fuel comes out.
 

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Discussion Starter · #9 ·
I can't get any fuel through it with the the hand pump. I think it may have gotten clogged. When I took a look the under the timing cover I saw it is really dirty inside. I'd like to remove it for a closer look...

BUT,

How do I get the thing off? The bolts holding it on have some weird star head I've never seen before. It is like I need a female Torx socket or something. Could that be?
 

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for a fuel filter change I would have bled the filter and started it, no need to have cracked all the screws and lines IMO.

since you allready have air in the system, might as well have a look at the condition of the primer pump, unclip the retainer screw "bail" and this allows you to pull the whole guts out. if there is tore rubber with chunks missing, the plunger is shot and needs replaced. if it pumps hard, I dont think its wore out though. a good sealing plunger will not be easy to pump.

what we feel helps when a guy is pumping the plunger, is to have the key on to have the fuel shutoff solenoid energized. I beleive this allows more fuel through the pump.

you should be able to hear it eventually slosh back into the tank via the return line.

do you have a strong flow from the tank? if yours is a 76, it could have the standpipe screen that could be clogged if the flow isnt very good.

good luck!
 

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Discussion Starter · #12 · (Edited)
NW Oregon try a 12 point socket I sure that's what it is.
Yep, that is what it was. I guess that should have figured that out, but apparently it is hard to think of when you can't see it.

I have good flow from the tank to the pump, but no flow trough the pump. I took the timing window off and the inside of the pump was brown and dirty. The pump is now sent off getting rebuilt. It sounds like the pump rebuild is going to cost close to half of what I paid for the whole combine in the first place.
 

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Discussion Starter · #15 ·
When I took the pump off I turned the engine until the timing mark in the pump was showing. That is top dead center, right? So when I stick the pump back on the engine should still be top dead center and the pump should be too, I think. Should I just be able to put it back together or do I need to time it?
 

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Your method should work as long as there is only one timing mark and no one has rotated the engine since the pump was removed. It's actually a good way to go about it for what you are doing.

I can't say if the marking system would be at TDC, or at the firing position BTDC.
 

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I doubt if its out of time if you put it back on in the same position without turning the engine over. Have you turned the pump on and purged it with the hand pump then cranked the engine with the lines loose up at the injectors until some diesel comes out around those fittings? It isn't good enough to just purge the injector lines down on the pump.
 

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Discussion Starter · #19 ·
I doubt if its out of time if you put it back on in the same position without turning the engine over.
I don't think I did that part successfully. I started to take it apart before I set it to TDC (based on the mark in the pump) and I thought I got it back, but something must have moved.

I primed it and had fuel coming out at each injector, so I think I got that right.

I'm not sure how to time this. Is there a timing mark on the flywheel? Can I take the valve cover of and go off the valves?
 
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