# John Deere 5105 engine problem



## Euclid (Sep 23, 2015)

Hi,

I inherited a 10 year old John Deere 5105 with a house in January. I've read the manual, done a few maintenance checks, and used it about 15 hours to bush hog a hilly field. This evening I had my first problem.

I had bush-hogged for an hour, and it had started raining for a few minutes when the tractor died. I was nearly on the level at the bottom of a hill. It was very low on fuel, so I put a few gallons of fresh diesel in it, using a can that I'd used before.

When I tried to start it, the engine turned over fine, but it took 6 or 7 tries before it started. Then it ran fine and revved up quickly for maybe 15 seconds before it slowly died again. It didn't sputter, but the rpms dropped and surged over 5 or 10 seconds. Over the next 10 or 15 minutes I repeated this a few times and managed to travel 50 feet before I gave up.

The owner's manual suggests the following possibilities:
* Air in fuel tank. (Bleed fuel tank.)
* Water, dirt, or air in fuel system. (Drain, flush, fill and bleed system.)
* Clogged fuel filter. (Replace filter element.)
* Dirty or faulty injectors. (Have John Deere dealer check injectors. )

Here's a clue. I opened the fuel/water drain plug a few times during this process and never had any fuel run out.

Anybody want to hazard a guess? I'm thinking maybe air in the fuel lines.

Thanks.


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## harry16 (Dec 8, 2011)

Hi Euclid,

Welcome to the tractor forum.

Whenever you run a diesel engine low on fuel, there is a risk of getting air into the system. You will have to purge air out of the entire system, starting with the filter. Your manual should have a procedure for purging air, as this is a common problem. 

Some diesels can be a PITA to get started after getting air into the system. You will learn to never let your diesel run low on fuel....

If your manual doesn't cover this topic, let us know and someone here will go over it with you.


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## Euclid (Sep 23, 2015)

Harry,
Thanks for your reply. 
The manual says:

1. Fuel tank must be full of fuel.
2. Loosen fuel return line (A). Loosen filter base bleed screw (B). Push priming pump (C) until fuel runs out smoothly without spitting, then tighten bleed screw (B).
3. Loosen injection pump bleed screw (D). Push priming pump (C) until fuel runs out smoothly without spitting, then tighten fuel return line (A) and bleed screw (D). 

Does that cover it?

Thanks,

Luke


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## harry16 (Dec 8, 2011)

That should cover it. Give it a try. If it won't start, repeat this procedure. Let us know if you are having problems.


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## Euclid (Sep 23, 2015)

Well, it didn't work. I did all the steps below and pumped hundreds and hundreds of times, but fuel never ran out of either the filter base bleed or the injection pump bleed. It would sputter occasionally, but no flow. When I tried to crank it, I got the same behavior as yesterday: eventually crank and run for 15 seconds before slowly dying.
I removed the fuel/water filter and it was about full of fuel.
I noticed a few weeks ago when going through the previous owner's receipts that he had replaced the primer pump. It sure seems like the primer pump isn't working, but could it be something else causing this?

Thanks. 




Euclid said:


> Harry,
> Thanks for your reply.
> The manual says:
> 
> ...


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## n194060 (Sep 5, 2015)

Sounds like blockage in the tank or lines to the fuel filters. Place a bucket under your tanks shutoff valve and open it up. If it flows trouble is likely in line to fuel filters and must be disconnected and blown out. More than likely it is a blockage in the base of the tank. Gently stick a screwdriver up the hole where you removed the shutoff valve and it should gush out. Quickly screw back in the valve. With everything back together open the bleeder screw on your filters and it should be squirting out now. Hope this solves your problem.


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## Euclid (Sep 23, 2015)

How do I figure out where the tank shutoff valve is? Do I need to buy a service manual?

Thanks.



n194060 said:


> Sounds like blockage in the tank or lines to the fuel filters. Place a bucket under your tanks shutoff valve and open it up. If it flows trouble is likely in line to fuel filters and must be disconnected and blown out. More than likely it is a blockage in the base of the tank. Gently stick a screwdriver up the hole where you removed the shutoff valve and it should gush out. Quickly screw back in the valve. With everything back together open the bleeder screw on your filters and it should be squirting out now. Hope this solves your problem.


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## n194060 (Sep 5, 2015)

Right at the very bottom of the gas tank should be a wing nut with a fuel line going towards your fuel filters. Counter clockwise to open reverse to shut. Should be easy to trace back from the fuel filter. Owners manual should show this. If you plan on keeping this awhile the shop manual is good for the bigger jobs but basic stuff should be covered in the owners manual like shutoff valve filter bleed screw etc.


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## Euclid (Sep 23, 2015)

Thanks. I'll look for it the next time that I'm out there.



n194060 said:


> Right at the very bottom of the gas tank should be a wing nut with a fuel line going towards your fuel filters. Counter clockwise to open reverse to shut. Should be easy to trace back from the fuel filter. Owners manual should show this. If you plan on keeping this awhile the shop manual is good for the bigger jobs but basic stuff should be covered in the owners manual like shutoff valve filter bleed screw etc.


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## Euclid (Sep 23, 2015)

It's running again! Whew.

I blew compressed air at the fuel tank opening. That got fuel flowing from the filter valve when I pushed the pump. The line was clear over to the fuel pump.
Then I blew air through the fuel pump a couple of times, and it finally fixed it. I hope whatever junk was in there somehow just disappears. 

Thanks *very* much for all the helpful advice!


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## n194060 (Sep 5, 2015)

Glad it worked out.


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