1HZ Injection Pump Question (1 Viewer)

[Bazz]

Hey all,

I recently replaced the diesel injection pump on my ‘93 HZJ73 and now it won’t start, just keeps cranking. Was working fine before, just had a leak.

I’ve given the filter about 20 pumps and have cranked it a total of maybe 30 seconds to a minute over several attempts.

Is it normal for it to take this long to get fuel through the pump and turn over? Something I’m missing? Could it be anything else?

Thanks!

 

[HZJ75 FARMER]

Hey all,

I recently replaced the diesel injection pump on my ‘93 HZJ73 and now it won’t start, just keeps cranking. Was working fine before, just had a leak.

I’ve given the filter about 20 pumps and have cranked it a total of maybe 30 seconds to a minute over several attempts.

Is it normal for it to take this long to get fuel through the pump and turn over? Something I’m missing? Could it be anything else?

Thanks!

Have you bled the injector lines?

Did you set the timing correctly?

Did you connect the wire to fuel solenoid, and verified that it's working?

 

[Bazz]

Have you bled the injector lines?

Did you set the timing correctly?

Did you connect the wire to fuel solenoid, and verified that it's working?

All I really did was remove it to replace some seals and then put it back in. All the pulleys were aligned and I didn’t move anything from its original position, pulleys or the pump.

I was hoping I wouldn’t need to check timing under this scenario, but I’m an idiot so I’m probably wrong there.

Wire is connected fine and nothing changed.

I definitely have not bled the injector lines.

 

[HZJ75 FARMER]

All I really did was remove it to replace some seals and then put it back in. All the pulleys were aligned and I didn’t move anything from its original position, pulleys or the pump.

I was hoping I wouldn’t need to check timing under this scenario, but I’m an idiot so I’m probably wrong there.

Wire is connected fine and nothing changed.

I definitely have not bled the injector lines.

Bleed the injector lines. That will tell you if you have fuel to the injectors.

If you have fuel to the injectors, it's probably a timing problem.

If you don't have fuel to the injectors, it's a fuel supply problem.

 

[OGBeno]

Whenever IP is removed it needs to be timed to the engine again.

It’s the heart of a diesel.

And what @HZJ75 FARMER said.

 

[Eurasiaoverland]

Just having the IP slightly mis-timed (alignment relative to the engine) will not stop it from starting. Have you lined the matchmarks up on the pump flange and timing cover?

How much disassembly did you do on the pump? Did you have the top cover off? Are you sure you replaced the governor adjusting spring (which goes between the governor and the accelerator crank)?

In my experience rotary pumps self prime if cranked long enough, but you can bleed air out at the injectors or the return union on top of the pump.

 

[Bazz]

Match mark are lined up, and they were prior to removal. I didn’t remove the top cover because that was the first thing I replaced a while ago to stop the leak and it worked just fine after (aside from not stopping the leaking).

Reading more on the timing procedure it seems foolish to think I could do this without timing it, haha.

Gonna check that fuel is getting to the injectors first but I have a feeling my timing is off to the point it’s not starting.

Thanks gentlemen.

 

[Eurasiaoverland]

I am not too familiar with the 1HZ, but are you saying that you removed and reinstalled the pump without checking the timing marks on the gears/belt pulleys? That could have more serious consequences, such as pistons hitting valves.

If timing gear/belt marks were aligned, and the external matchmark is aligned, there is no more timing to be done. You could verify the plunger stroke with a dial indicator (which is a direct proxy of timing), but being slightly out would not stop the engine starting.

 

[Bazz]

I am not too familiar with the 1HZ, but are you saying that you removed and reinstalled the pump without checking the timing marks on the gears/belt pulleys? That could have more serious consequences, such as pistons hitting valves.

If timing gear/belt marks were aligned, and the external matchmark is aligned, there is no more timing to be done. You could verify the plunger stroke with a dial indicator (which is a direct proxy of timing), but being slightly out would not stop the engine starting.

I definitely lined up both pulley match marks before removing the belt and pump and ensured everything was lined up when putting it back together.

 

[Eurasiaoverland]

I definitely lined up both pulley match marks before removing the belt and pump and ensured everything was lined up when putting it back together.

OK, then if everything is aligned, timing is not the issue.

 

[Bazz]

Ok so I got it running.

For reference, anyone reading this later.

I wasn’t getting any fuel out of the upper fuel outlet, and definitely not to the injectors. Must have pumped vigorously for 2+ minutes () and prob 2 min total of cranking, so I knew it was a fuel problem.

I bought a fluid pump, filled my can, turned on the key to get the solenoid on, and started pumping.

I noticed some leaking around the inlet pipe screw, so I torqued that down, and started pumping again. This time I got fuel out of the outlet hose.

I hooked everything back up hoping I’d fixed the issue and with about 5 seconds of cranking she went, and after another 5 seconds she’s running perfectly.

The sad part is that the leak is still there, so the real moral of this story is just to take the time to get it rebuilt and don’t be in a rush. I’m not doing that again any time soon, so I guess I’ll live with the leak for another 2 years…

Timing SST will arrive in the next few days so I’ll be doing that soon.

 

[Eurasiaoverland]

The inlet pipe is a banjo type fitting with 3 non-reusable copper crush washers (one under the hollow screw fitting and one either side of the inlet pipe) which are very easy to replace, no pump removal required. If the cap nut is bad, they are cheap to replace too. https://partsouq.com/en/search/all?q=9009905161

If you have diesel leaking out from inlet pipe, it's very likely that air will get in and you'll have further problems losing prime.

 

[Bazz]

The inlet pipe is a banjo type fitting with 3 non-reusable copper crush washers (one under the hollow screw fitting and one either side of the inlet pipe) which are very easy to replace, no pump removal required. If the cap nut is bad, they are cheap to replace too. https://partsouq.com/en/search/all?q=9009905161

If you have diesel leaking out from inlet pipe, it's very likely that air will get in and you'll have further problems losing prime.

Fortunately the inlet pipe isn't leaking anymore, I just forgot to torque that down after install since I didn't have it in a vice when I was doing the seals. I'll put my camera scope down there and see if I can locate where the leak is coming from. If it's easily accessible I'll try to do that one again before giving in. Thanks for the help @Eurasiaoverland