d1105 injectors don't spray.

[awitty]

Hi


I'm trying to resurrect a Kubota d1105 engine that's been sat idle in my barn for about 10 years. I'm a bit of a novice when it comes to engines so I thought I would dive straight in and use it to teach myself some new skills.

However, I'm having trouble getting it to start and have tried just about everything including;

1) new fuel and filter
2) verified the glow plugs are working.
3) checked the fuel cut off solenoid is ok
4) removed the air from the injector lines.
5) compression checked each cylinder (about 400psi)

After scratching my head for a few days I removed the injectors but kept them still attached to the rail to double check they were spraying fuel, and was surprised to see absolutely nothing. Not one drop of fuel coming out of the injectors. Thinking there may be an air lock I loosened up the injector pipe connectors (at the injector end) and fuel spurts out of each when I crank the engine. But nothing out of the injectors when I tighten them up again.

I'm a bit stuck. Could all injectors be faulty ? (seems unlikely they've all failed) or do I have a problem with the injection pump despite it clearly delivering fuel to the top of the injector?

I did remove the injector pump and it looks ok with the three spring rollers are looking like they should.

Any advice?

 

[BruceP]

Injection pump!

Perhaps the pump still has air bubbles in it?
Perhaps the lever is stuck in the "stop" position?

 

[awitty]

Injection pump!

Perhaps the pump still has air bubbles in it?
Perhaps the lever is stuck in the "stop" position?

Maybe, but i have run it for a while with the injector lines cracked and it's spitting out plenty of fuel as the engine cranks.
I also opened up the air bleeder valve and that again just shoots out fuel.

If i'm getting fuel to the injectors then the lever can't be in the stop position can it ? or have I misunderstood.

 

[lugbolt]

you can get fuel to the injunktors but what is the pressure? Is the pressure high enough to pop the injectors?

Testing them like that a sometimes you never see the fuel. It comes out at, what, 1000-3500 psi, and finely atomized. In the past I've had to use a piece of notebook paper to spray against, held about 3-4" away from the nozzle tip. It is then obvious if there is any injection taking place.

 

[awitty]

you can get fuel to the injunktors but what is the pressure? Is the pressure high enough to pop the injectors?

Testing them like that a sometimes you never see the fuel. It comes out at, what, 1000-3500 psi, and finely atomized. In the past I've had to use a piece of notebook paper to spray against, held about 3-4" away from the nozzle tip. It is then obvious if there is any injection taking place.

I don't have anything to test the injector pressure. Is there a fudge where i could use the same bit of kit I did the cylinder compression test with? I'll google.

I tried the notebook paper and there is definitely nothing coming out of the injectors.

Scratching head time..

 

[JerryMT]

I don't have anything to test the injector pressure. Is there a fudge where i could use the same bit of kit I did the cylinder compression test with? I'll google.

I tried the notebook paper and there is definitely nothing coming out of the injectors.

Scratching head time..

You've gone this far and you apparently have fuel being delivered by the injection pump (IP) so why not send the injectors out for cleaning and testing? If this engine sat in a barn unused for 10 years, maybe the injectors are crudded up and won't open.

 

[D2Cat]

As mentioned remove the injectors and take them to a nearby injection pump service shop. They can test the injectors.

Be cautious of the pressures you're dealing with and DO NOT get you hands (or anything else) in the path of the high pressure fuel lines. That pressure will cause the fuel to penetrate your skin.

 

[awitty]

Thanks guys. I've ordered myself an injector nozzle pop pressure tester. They're fairly inexpensive so it seems a more cost effective way of finding out whether the injectors are full of crud.

Thanks for the warning about the high pressure from the jets. I did see similar warnings on various youtube videos.

 

[awitty]

Success !


So I ordered a cheap injector tester (see here) and tested all 3 injectors. All 3 popped somewhere between 11-12 Mpa (which converts to about 1600-1750 psi). I then put them back on the machine and managed to get one to fire, but nothing from the others. So i swapped them about and the good injector worked wherever I put it ( i.e. proves nothing wrong with the pump).

I then checked them again on the tester (similar Mpa) but gave them a good 20-30 squirts each. I then put them back on the machine and hey presto all firing !

Once I got them back in the cylinder head she actually fired up for about 5 seconds which is the first time she's fired in over 10 years.

Just have to figure out how to keep her going now!

 

[Nicksacco]

Excellent - Good for you.
I'm thinking the injector was clogged and using the tool managed to get them going again.
They could still be clogged and if the engine doesn't continue to run, perhaps put them in the tool again just to ensure they are popping.

Looks like the injectors come apart same as mine do in the D1703. Here are a couple of pics if you decide to disassemble and clean yourself.

This video around 2:30 talks about it.

Your injector

NEW GENUINE KUBOTA INJECTOR FOR '05' SERIES DIESEL ENGINES D1005 D1105 | eBay

Find many great new & used options and get the best deals for NEW GENUINE KUBOTA INJECTOR FOR '05' SERIES DIESEL ENGINES D1005 D1105 at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[awitty]

Excellent - Good for you.
I'm thinking the injector was clogged and using the tool managed to get them going again.
They could still be clogged and if the engine doesn't continue to run, perhaps put them in the tool again just to ensure they are popping.

Looks like the injectors come apart same as mine do in the D1703. Here are a couple of pics if you decide to disassemble and clean yourself.

This video around 2:30 talks about it.

Your injector

NEW GENUINE KUBOTA INJECTOR FOR '05' SERIES DIESEL ENGINES D1005 D1105 | eBay

Find many great new & used options and get the best deals for NEW GENUINE KUBOTA INJECTOR FOR '05' SERIES DIESEL ENGINES D1005 D1105 at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I came to the same conclusion that the tester helped give them a good cleanout. Although i may follow your advice and take them apart if it still continues to struggle. Thank for the links.

 

[D2Cat]

Nice feeling, isn't it! Nothing is more satisfying then getting a piece of machinery going after it's been out of commission for a while